Intermountain West Dashboard | Western Water Assessment

Intermountain West Dashboard | Western Water Assessment
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Intermountain West Dashboard
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The Intermountain West Dashboard provides situational awareness of weather, drought, and water resources for Colorado, Utah, and Wyoming.
Click the question mark icon above each graphic to see the description of that graphic.
Weekly or monthly summaries of evolving weather, drought, and water conditions for the Intermountain West are also available from these providers:
Colorado CC/NIDIS
Intermountain West Drought Status Briefings
NOAA CBRFC
Water Supply Briefings for the Colorado River Basin and Great Basin
- monthly, January through May
NRCS Water Supply Outlook Reports
for
Colorado
Utah
, and
Wyoming
- monthly, January through May/June
View the latest briefing
Temperature, Precipitation and Snowpack
30-day Temp. Anomaly
(HPRCC)
( updated daily )
30-day Temp. Anomaly
HPRCC
Recent Temperature and Precipitation Maps
The temperature and precipitation maps are derived from observations at individual meteorological stations in the National Weather Service Cooperative Observer Network (COOP), and the Automated Weather Data Network (AWDN). Interpolation (estimation) of values between these known points is performed to produce continuous shaded contours. Interpolation procedures can cause incorrect values in data-sparse regions.
Note that observations from NRCS SNOTEL sites are
not
included in these maps; therefore, most high mountain areas are in the “data-sparse” regions subject to interpolation errors, if the climate anomalies differ between mountain areas and the nearest COOP and AWDN stations, at lower elevations.
These maps are products of the High Plains Regional Climate Center (HPRCC), using data delivered through the Applied Climate Information System (ACIS) developed at the University of Nebraska-Lincoln. These near-real-time data should be considered to be preliminary, having been subjected to minimal quality control.
In these maps, “average” refers to the 1991-2020 climate normal. Maps generated before May 4, 2021 used the 1981–2010 climate normal.
For additional temperature and precipitation maps, and for maps of other climate variables including individual station data, visit
HPRCC
30-day Precip as % Avg
(HPRCC)
( updated daily )
30-day Precip as % Avg
HPRCC
Recent Temperature and Precipitation Maps
The temperature and precipitation maps are derived from observations at individual meteorological stations in the National Weather Service Cooperative Observer Network (COOP), and the Automated Weather Data Network (AWDN). Interpolation (estimation) of values between these known points is performed to produce continuous shaded contours. Interpolation procedures can cause incorrect values in data-sparse regions.
Note that observations from NRCS SNOTEL sites are
not
included in these maps; therefore, most high mountain areas are in the “data-sparse” regions subject to interpolation errors, if the climate anomalies differ between mountain areas and the nearest COOP and AWDN stations, at lower elevations.
These maps are products of the High Plains Regional Climate Center (HPRCC), using data delivered through the Applied Climate Information System (ACIS) developed at the University of Nebraska-Lincoln. These near-real-time data should be considered to be preliminary, having been subjected to minimal quality control.
In these maps, “average” refers to the 1991-2020 climate normal. Maps generated before May 4, 2021 used the 1981–2010 climate normal.
For additional temperature and precipitation maps, and for maps of other climate variables including individual station data, visit
HPRCC
Water-Year Precip as % Avg
(HPRCC)
( updated daily )
Water-Year Precip as % Avg
HPRCC
Recent Temperature and Precipitation Maps
The temperature and precipitation maps are derived from observations at individual meteorological stations in the National Weather Service Cooperative Observer Network (COOP), and the Automated Weather Data Network (AWDN). Interpolation (estimation) of values between these known points is performed to produce continuous shaded contours. Interpolation procedures can cause incorrect values in data-sparse regions.
Note that observations from NRCS SNOTEL sites are
not
included in these maps; therefore, most high mountain areas are in the “data-sparse” regions subject to interpolation errors, if the climate anomalies differ between mountain areas and the nearest COOP and AWDN stations, at lower elevations.
These maps are products of the High Plains Regional Climate Center (HPRCC), using data delivered through the Applied Climate Information System (ACIS) developed at the University of Nebraska-Lincoln. These near-real-time data should be considered to be preliminary, having been subjected to minimal quality control.
In these maps, “average” refers to the 1991-2020 climate normal. Maps generated before May 4, 2021 used the 1981–2010 climate normal.
For additional temperature and precipitation maps, and for maps of other climate variables including individual station data, visit
HPRCC
Current Snowpack - Western U.S.
(NRCS)
( updated weekly )
Current Snowpack - Western U.S.
NRCS
Current Snowpack as % of Normal Map
Snowpack telemetry (SNOTEL) sites are automated stations operated by the USDA Natural Resources Conservation Service (NRCS) that measure snow water equivalent (SWE), the depth of water that would result by melting the snowpack at the measurement site. SWE is determined by measuring the weight of snow resting on a pressure-sensitive pillow (like a very large bathroom scale) at the SNOTEL site, and converting that measurement into inches of water equivalent.
The Current Snowpack as % of Normal map from NRCS depicts the conditions averaged across a set of SNOTEL sites that are either within or immediately adjacent to the outlined basin. For each SNOTEL site that is actively reporting data, the current SWE is calculated as percentage of the historic (1991-2020) median SWE for that date. Then for each basin, these % of normal values for active SNOTEL sites are averaged across each basin to generate the % of normal value for that basin. The number of SNOTEL sites representing each basin ranges from 1 to 31, depending on the basin and the number of actively reporting sites.
This table
from NRCS has the same data as in the map, but also reports the number of SNOTEL sites reporting for each basin.
Note that SNOTEL sites are point samples of complex and spatially variable basin snowpacks. Collectively, the SNOTEL sites within a basin may over- or under-estimate actual basin snow conditions, particularly if the highest and lowest elevations in a given basin (which have fewer SNOTEL sites) have unusual snowpack anomalies. Also, not all SNOTEL sites may be reporting on a given day.
For additional SNOTEL maps visit NRCS
here
For State Basin Outlook Reports, visit NRCS
here
and select the state from the dropdown menu.
Current Snowpack - Colorado
(NRCS)
( updated weekly )
Current Snowpack - Colorado
NRCS
Current Snowpack as % of Normal Map
Snowpack telemetry (SNOTEL) sites are automated stations operated by the USDA Natural Resources Conservation Service (NRCS) that measure snow water equivalent (SWE), the depth of water that would result by melting the snowpack at the measurement site. SWE is determined by measuring the weight of snow resting on a pressure-sensitive pillow (like a very large bathroom scale) at the SNOTEL site, and converting that measurement into inches of water equivalent.
The Current Snowpack as % of Normal map from NRCS depicts the conditions averaged across a set of SNOTEL sites that are either within or immediately adjacent to the outlined basin. For each SNOTEL site that is actively reporting data, the current SWE is calculated as percentage of the historic (1991-2020) median SWE for that date. Then for each basin, these % of normal values for active SNOTEL sites are averaged across each basin to generate the % of normal value for that basin. The number of SNOTEL sites representing each basin ranges from 1 to 31, depending on the basin and the number of actively reporting sites.
This table
from NRCS has the same data as in the map, but also reports the number of SNOTEL sites reporting for each basin.
Note that SNOTEL sites are point samples of complex and spatially variable basin snowpacks. Collectively, the SNOTEL sites within a basin may over- or under-estimate actual basin snow conditions, particularly if the highest and lowest elevations in a given basin (which have fewer SNOTEL sites) have unusual snowpack anomalies. Also, not all SNOTEL sites may be reporting on a given day.
For additional SNOTEL maps visit NRCS
here
For State Basin Outlook Reports, visit NRCS
here
and select the state from the dropdown menu.
Current Snowpack - Utah
(NRCS)
( updated weekly )
Current Snowpack - Utah
NRCS
Current Snowpack as % of Normal Map
Snowpack telemetry (SNOTEL) sites are automated stations operated by the USDA Natural Resources Conservation Service (NRCS) that measure snow water equivalent (SWE), the depth of water that would result by melting the snowpack at the measurement site. SWE is determined by measuring the weight of snow resting on a pressure-sensitive pillow (like a very large bathroom scale) at the SNOTEL site, and converting that measurement into inches of water equivalent.
The Current Snowpack as % of Normal map from NRCS depicts the conditions averaged across a set of SNOTEL sites that are either within or immediately adjacent to the outlined basin. For each SNOTEL site that is actively reporting data, the current SWE is calculated as percentage of the historic (1991-2020) median SWE for that date. Then for each basin, these % of normal values for active SNOTEL sites are averaged across each basin to generate the % of normal value for that basin. The number of SNOTEL sites representing each basin ranges from 1 to 31, depending on the basin and the number of actively reporting sites.
This table
from NRCS has the same data as in the map, but also reports the number of SNOTEL sites reporting for each basin.
Note that SNOTEL sites are point samples of complex and spatially variable basin snowpacks. Collectively, the SNOTEL sites within a basin may over- or under-estimate actual basin snow conditions, particularly if the highest and lowest elevations in a given basin (which have fewer SNOTEL sites) have unusual snowpack anomalies. Also, not all SNOTEL sites may be reporting on a given day.
For additional SNOTEL maps visit NRCS
here
For State Basin Outlook Reports, visit NRCS
here
and select the state from the dropdown menu.
Current Snowpack - Wyoming
(NRCS)
( updated weekly )
Current Snowpack - Wyoming
NRCS
Current Snowpack as % of Normal Map
Snowpack telemetry (SNOTEL) sites are automated stations operated by the USDA Natural Resources Conservation Service (NRCS) that measure snow water equivalent (SWE), the depth of water that would result by melting the snowpack at the measurement site. SWE is determined by measuring the weight of snow resting on a pressure-sensitive pillow (like a very large bathroom scale) at the SNOTEL site, and converting that measurement into inches of water equivalent.
The Current Snowpack as % of Normal map from NRCS depicts the conditions averaged across a set of SNOTEL sites that are either within or immediately adjacent to the outlined basin. For each SNOTEL site that is actively reporting data, the current SWE is calculated as percentage of the historic (1991-2020) median SWE for that date. Then for each basin, these % of normal values for active SNOTEL sites are averaged across each basin to generate the % of normal value for that basin. The number of SNOTEL sites representing each basin ranges from 1 to 31, depending on the basin and the number of actively reporting sites.
This table
from NRCS has the same data as in the map, but also reports the number of SNOTEL sites reporting for each basin.
Note that SNOTEL sites are point samples of complex and spatially variable basin snowpacks. Collectively, the SNOTEL sites within a basin may over- or under-estimate actual basin snow conditions, particularly if the highest and lowest elevations in a given basin (which have fewer SNOTEL sites) have unusual snowpack anomalies. Also, not all SNOTEL sites may be reporting on a given day.
For additional SNOTEL maps visit NRCS
here
For State Basin Outlook Reports, visit NRCS
here
and select the state from the dropdown menu.
Spatial SWE Estimates
Info
( monthly )
Spatial SWE Estimates
Custom Dashboard Info
Spatial SWE estimates are provided from an experimental research product that provides near-real-time estimates of SWE at a spatial resolution of 500 meters for the Intermountain West region (Colorado, Utah and Wyoming) from mid-winter through the melt season. The report is typically released within a week of the date of data acquisition. A full report is available in pdf format online (click on Spatial SWE Estimates on dashboard).
Drought Conditions
US Drought Monitor
(NDMC)
( updated weekly )
US Drought Monitor
NDMC
US Drought Monitor
The US Drought Monitor maps are based on expert synthesis of drought indicators including (but not limited to) the Palmer Drought Severity Index, soil moisture, streamflow, precipitation, and measures of vegetation stress, as well as reports of drought impacts. The USDM categories are assigned so that they
generally
correspond with one or more of the objectively measured indicators, listed above, being in these percentile classes:
D0 (abnormal dryness) – 20th-30th percentile
D1 (moderate drought) – 10th-20th percentile
D2 (severe drought) – 5th-10th percentile
D3 (extreme drought) – 2nd-5th percentile
D4 (exceptional drought) – 0th-2nd percentile
The USDM is produced in partnership between the National Drought Mitigation Center (NDMC) at the University of Nebraska-Lincoln, the United States Department of Agriculture, and NOAA. The US Drought Monitor is released weekly (every Thursday) by the NDMC, and it represents data collected through that Tuesday. Both academic and government drought experts participate in weekly calls to discuss changes to the forthcoming USDM, and this input is compiled by the author(s) named on each week’s map.
The weekly state USDM maps for Colorado, Utah, and Wyoming show the same drought categories and boundaries as the nationwide map, but at a higher spatial resolution and with the county boundaries shown, so that local conditions can be more easily discerned.
Each USDM is released with a text discussion that provides supporting detail on drought conditions in different parts of the country.
US Drought Monitor - Western US
(NDMC)
( updated weekly )
US Drought Monitor - Western US
NDMC
US Drought Monitor
The US Drought Monitor maps are based on expert synthesis of drought indicators including (but not limited to) the Palmer Drought Severity Index, soil moisture, streamflow, precipitation, and measures of vegetation stress, as well as reports of drought impacts. The USDM categories are assigned so that they
generally
correspond with one or more of the objectively measured indicators, listed above, being in these percentile classes:
D0 (abnormal dryness) – 20th-30th percentile
D1 (moderate drought) – 10th-20th percentile
D2 (severe drought) – 5th-10th percentile
D3 (extreme drought) – 2nd-5th percentile
D4 (exceptional drought) – 0th-2nd percentile
The USDM is produced in partnership between the National Drought Mitigation Center (NDMC) at the University of Nebraska-Lincoln, the United States Department of Agriculture, and NOAA. The US Drought Monitor is released weekly (every Thursday) by the NDMC, and it represents data collected through that Tuesday. Both academic and government drought experts participate in weekly calls to discuss changes to the forthcoming USDM, and this input is compiled by the author(s) named on each week’s map.
The weekly state USDM maps for Colorado, Utah, and Wyoming show the same drought categories and boundaries as the nationwide map, but at a higher spatial resolution and with the county boundaries shown, so that local conditions can be more easily discerned.
Each USDM is released with a text discussion that provides supporting detail on drought conditions in different parts of the country.
US Drought Monitor
(NDMC)
Wyoming
( updated weekly )
US Drought Monitor
NDMC
US Drought Monitor
The US Drought Monitor maps are based on expert synthesis of drought indicators including (but not limited to) the Palmer Drought Severity Index, soil moisture, streamflow, precipitation, and measures of vegetation stress, as well as reports of drought impacts. The USDM categories are assigned so that they
generally
correspond with one or more of the objectively measured indicators, listed above, being in these percentile classes:
D0 (abnormal dryness) – 20th-30th percentile
D1 (moderate drought) – 10th-20th percentile
D2 (severe drought) – 5th-10th percentile
D3 (extreme drought) – 2nd-5th percentile
D4 (exceptional drought) – 0th-2nd percentile
The USDM is produced in partnership between the National Drought Mitigation Center (NDMC) at the University of Nebraska-Lincoln, the United States Department of Agriculture, and NOAA. The US Drought Monitor is released weekly (every Thursday) by the NDMC, and it represents data collected through that Tuesday. Both academic and government drought experts participate in weekly calls to discuss changes to the forthcoming USDM, and this input is compiled by the author(s) named on each week’s map.
The weekly state USDM maps for Colorado, Utah, and Wyoming show the same drought categories and boundaries as the nationwide map, but at a higher spatial resolution and with the county boundaries shown, so that local conditions can be more easily discerned.
Each USDM is released with a text discussion that provides supporting detail on drought conditions in different parts of the country.
US Drought Monitor
(NDMC)
Utah
( updated weekly )
US Drought Monitor
NDMC
US Drought Monitor
The US Drought Monitor maps are based on expert synthesis of drought indicators including (but not limited to) the Palmer Drought Severity Index, soil moisture, streamflow, precipitation, and measures of vegetation stress, as well as reports of drought impacts. The USDM categories are assigned so that they
generally
correspond with one or more of the objectively measured indicators, listed above, being in these percentile classes:
D0 (abnormal dryness) – 20th-30th percentile
D1 (moderate drought) – 10th-20th percentile
D2 (severe drought) – 5th-10th percentile
D3 (extreme drought) – 2nd-5th percentile
D4 (exceptional drought) – 0th-2nd percentile
The USDM is produced in partnership between the National Drought Mitigation Center (NDMC) at the University of Nebraska-Lincoln, the United States Department of Agriculture, and NOAA. The US Drought Monitor is released weekly (every Thursday) by the NDMC, and it represents data collected through that Tuesday. Both academic and government drought experts participate in weekly calls to discuss changes to the forthcoming USDM, and this input is compiled by the author(s) named on each week’s map.
The weekly state USDM maps for Colorado, Utah, and Wyoming show the same drought categories and boundaries as the nationwide map, but at a higher spatial resolution and with the county boundaries shown, so that local conditions can be more easily discerned.
Each USDM is released with a text discussion that provides supporting detail on drought conditions in different parts of the country.
US Drought Monitor
(NDMC)
Colorado
( updated weekly )
US Drought Monitor
NDMC
US Drought Monitor
The US Drought Monitor maps are based on expert synthesis of drought indicators including (but not limited to) the Palmer Drought Severity Index, soil moisture, streamflow, precipitation, and measures of vegetation stress, as well as reports of drought impacts. The USDM categories are assigned so that they
generally
correspond with one or more of the objectively measured indicators, listed above, being in these percentile classes:
D0 (abnormal dryness) – 20th-30th percentile
D1 (moderate drought) – 10th-20th percentile
D2 (severe drought) – 5th-10th percentile
D3 (extreme drought) – 2nd-5th percentile
D4 (exceptional drought) – 0th-2nd percentile
The USDM is produced in partnership between the National Drought Mitigation Center (NDMC) at the University of Nebraska-Lincoln, the United States Department of Agriculture, and NOAA. The US Drought Monitor is released weekly (every Thursday) by the NDMC, and it represents data collected through that Tuesday. Both academic and government drought experts participate in weekly calls to discuss changes to the forthcoming USDM, and this input is compiled by the author(s) named on each week’s map.
The weekly state USDM maps for Colorado, Utah, and Wyoming show the same drought categories and boundaries as the nationwide map, but at a higher spatial resolution and with the county boundaries shown, so that local conditions can be more easily discerned.
Each USDM is released with a text discussion that provides supporting detail on drought conditions in different parts of the country.
Standardized Precip Index (SPI)
(SPI)
( updated daily )
1-mo
Standardized Precip Index (SPI)
SPI
Standardized Precipitation Index
The SPI is a drought index, developed by then-Colorado state climatologist Thomas McKee and others, based on the historical probabilities of receiving a given amount of precipitation over a given period. The SPI was designed to explicitly capture that it is possible to simultaneously experience relatively wet conditions on one or more time scales, and relatively dry conditions at other time scales. Consequently, a separate SPI value is calculated for different time scales.
The SPI maps shown on the Dashboard are developed by the National Drought Mitigation Center (NDMC) and the High Plains Regional Climate Center (HPRCC). The HPRCC SPI maps shown here, updated daily, are
also available
at timescales of 1, 2, 4, 6, 9, and 24 months. The Western Regional Climate Center (WRCC) produces a
set of national SPI maps
showing values for each climate division, updated monthly, at timescales of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 18, 24, 30, 36, 48, 60, and 72 months.
The historical probabilities of receiving a given amount of precipitation are standardized so that an SPI of zero indicates the mean historical precipitation (1981-2010), and other SPI values correspond to the number of standard deviations that the observed precipitation value departs from the long-term mean, for a normally distributed random variable. Since precipitation is not normally distributed at most timescales in most regions, a transformation is first applied so that the transformed precipitation values follow a normal distribution.
An SPI value of -1 indicates moderate drought severity and means that only 16% of all periods would be expected to be drier. An SPI value of -2 indicates severe drought, with only 2.5% of periods would be expected to be drier. For more information on the SPI and how it is calculated see
this page
at the Western Regional Climate Center.
Standardized Precip Index (SPI)
(SPI)
( updated daily )
3-mo
Standardized Precip Index (SPI)
SPI
Standardized Precipitation Index
The SPI is a drought index, developed by then-Colorado state climatologist Thomas McKee and others, based on the historical probabilities of receiving a given amount of precipitation over a given period. The SPI was designed to explicitly capture that it is possible to simultaneously experience relatively wet conditions on one or more time scales, and relatively dry conditions at other time scales. Consequently, a separate SPI value is calculated for different time scales.
The SPI maps shown on the Dashboard are developed by the National Drought Mitigation Center (NDMC) and the High Plains Regional Climate Center (HPRCC). The HPRCC SPI maps shown here, updated daily, are
also available
at timescales of 1, 2, 4, 6, 9, and 24 months. The Western Regional Climate Center (WRCC) produces a
set of national SPI maps
showing values for each climate division, updated monthly, at timescales of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 18, 24, 30, 36, 48, 60, and 72 months.
The historical probabilities of receiving a given amount of precipitation are standardized so that an SPI of zero indicates the mean historical precipitation (1981-2010), and other SPI values correspond to the number of standard deviations that the observed precipitation value departs from the long-term mean, for a normally distributed random variable. Since precipitation is not normally distributed at most timescales in most regions, a transformation is first applied so that the transformed precipitation values follow a normal distribution.
An SPI value of -1 indicates moderate drought severity and means that only 16% of all periods would be expected to be drier. An SPI value of -2 indicates severe drought, with only 2.5% of periods would be expected to be drier. For more information on the SPI and how it is calculated see
this page
at the Western Regional Climate Center.
Standardized Precip Index (SPI)
(SPI)
( updated daily )
12-mo
Standardized Precip Index (SPI)
SPI
Standardized Precipitation Index
The SPI is a drought index, developed by then-Colorado state climatologist Thomas McKee and others, based on the historical probabilities of receiving a given amount of precipitation over a given period. The SPI was designed to explicitly capture that it is possible to simultaneously experience relatively wet conditions on one or more time scales, and relatively dry conditions at other time scales. Consequently, a separate SPI value is calculated for different time scales.
The SPI maps shown on the Dashboard are developed by the National Drought Mitigation Center (NDMC) and the High Plains Regional Climate Center (HPRCC). The HPRCC SPI maps shown here, updated daily, are
also available
at timescales of 1, 2, 4, 6, 9, and 24 months. The Western Regional Climate Center (WRCC) produces a
set of national SPI maps
showing values for each climate division, updated monthly, at timescales of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 15, 18, 24, 30, 36, 48, 60, and 72 months.
The historical probabilities of receiving a given amount of precipitation are standardized so that an SPI of zero indicates the mean historical precipitation (1981-2010), and other SPI values correspond to the number of standard deviations that the observed precipitation value departs from the long-term mean, for a normally distributed random variable. Since precipitation is not normally distributed at most timescales in most regions, a transformation is first applied so that the transformed precipitation values follow a normal distribution.
An SPI value of -1 indicates moderate drought severity and means that only 16% of all periods would be expected to be drier. An SPI value of -2 indicates severe drought, with only 2.5% of periods would be expected to be drier. For more information on the SPI and how it is calculated see
this page
at the Western Regional Climate Center.
Evaporative Demand Drought Index (EDDI)
(EDDI)
( updated daily )
2-wk
Evaporative Demand Drought Index (EDDI)
EDDI
Evaporative Demand Drought Index
The Evaporative Demand Drought Index (EDDI) exploits the strong physical relationship between evaporative demand (E0) and actual loss of water from the land surface through evapotranspiration. E0 is the “thirst of the atmosphere,” estimated by the amount of water that would evaporate from the soil and be transpired by plants if the soil were well watered. EDDI measures the signal of drought using information on the rapidly evolving (daily) conditions of the atmosphere to estimate their impact on land-surface moisture, and vice versa. EDDI’s effectiveness in reflecting the moisture conditions on the land surface is based on feedbacks between the atmosphere and land that are particularly strong during the warm season, when drought is of greatest concern. See the
EDDI User Guide
for more information.
The data used to generate these maps come from the North American Land Data Assimilation System Phase-2 (NLDAS-2) project, which assimilates observations of temperature, wind speed, radiation, and vapor pressure deficit. The date indicates the last day of the period of record, and the week number indicates the window size for the period of record.
The drought category shown (D0, D1, D2, D3, D4) is a function of the depth of reference evapotranspiration accumulated over a given period of record (4-week, 8-week, 12-week) with respect to a climatology of
1980-2015
. The drought categories are consistent with the US Drought Monitor's Percentile Ranking Scheme.
Evaporative Demand Drought Index (EDDI)
(EDDI)
( updated daily )
4-wk
Evaporative Demand Drought Index (EDDI)
EDDI
Evaporative Demand Drought Index
The Evaporative Demand Drought Index (EDDI) exploits the strong physical relationship between evaporative demand (E0) and actual loss of water from the land surface through evapotranspiration. E0 is the “thirst of the atmosphere,” estimated by the amount of water that would evaporate from the soil and be transpired by plants if the soil were well watered. EDDI measures the signal of drought using information on the rapidly evolving (daily) conditions of the atmosphere to estimate their impact on land-surface moisture, and vice versa. EDDI’s effectiveness in reflecting the moisture conditions on the land surface is based on feedbacks between the atmosphere and land that are particularly strong during the warm season, when drought is of greatest concern. See the
EDDI User Guide
for more information.
The data used to generate these maps come from the North American Land Data Assimilation System Phase-2 (NLDAS-2) project, which assimilates observations of temperature, wind speed, radiation, and vapor pressure deficit. The date indicates the last day of the period of record, and the week number indicates the window size for the period of record.
The drought category shown (D0, D1, D2, D3, D4) is a function of the depth of reference evapotranspiration accumulated over a given period of record (4-week, 8-week, 12-week) with respect to a climatology of
1980-2015
. The drought categories are consistent with the US Drought Monitor's Percentile Ranking Scheme.
Evaporative Demand Drought Index (EDDI)
(EDDI)
( updated daily )
3-mo
Evaporative Demand Drought Index (EDDI)
EDDI
Evaporative Demand Drought Index
The Evaporative Demand Drought Index (EDDI) exploits the strong physical relationship between evaporative demand (E0) and actual loss of water from the land surface through evapotranspiration. E0 is the “thirst of the atmosphere,” estimated by the amount of water that would evaporate from the soil and be transpired by plants if the soil were well watered. EDDI measures the signal of drought using information on the rapidly evolving (daily) conditions of the atmosphere to estimate their impact on land-surface moisture, and vice versa. EDDI’s effectiveness in reflecting the moisture conditions on the land surface is based on feedbacks between the atmosphere and land that are particularly strong during the warm season, when drought is of greatest concern. See the
EDDI User Guide
for more information.
The data used to generate these maps come from the North American Land Data Assimilation System Phase-2 (NLDAS-2) project, which assimilates observations of temperature, wind speed, radiation, and vapor pressure deficit. The date indicates the last day of the period of record, and the week number indicates the window size for the period of record.
The drought category shown (D0, D1, D2, D3, D4) is a function of the depth of reference evapotranspiration accumulated over a given period of record (4-week, 8-week, 12-week) with respect to a climatology of
1980-2015
. The drought categories are consistent with the US Drought Monitor's Percentile Ranking Scheme.
Evaporative Demand Drought Index (EDDI)
(EDDI)
( updated daily )
6-mo
Evaporative Demand Drought Index (EDDI)
EDDI
Evaporative Demand Drought Index
The Evaporative Demand Drought Index (EDDI) exploits the strong physical relationship between evaporative demand (E0) and actual loss of water from the land surface through evapotranspiration. E0 is the “thirst of the atmosphere,” estimated by the amount of water that would evaporate from the soil and be transpired by plants if the soil were well watered. EDDI measures the signal of drought using information on the rapidly evolving (daily) conditions of the atmosphere to estimate their impact on land-surface moisture, and vice versa. EDDI’s effectiveness in reflecting the moisture conditions on the land surface is based on feedbacks between the atmosphere and land that are particularly strong during the warm season, when drought is of greatest concern. See the
EDDI User Guide
for more information.
The data used to generate these maps come from the North American Land Data Assimilation System Phase-2 (NLDAS-2) project, which assimilates observations of temperature, wind speed, radiation, and vapor pressure deficit. The date indicates the last day of the period of record, and the week number indicates the window size for the period of record.
The drought category shown (D0, D1, D2, D3, D4) is a function of the depth of reference evapotranspiration accumulated over a given period of record (4-week, 8-week, 12-week) with respect to a climatology of
1980-2015
. The drought categories are consistent with the US Drought Monitor's Percentile Ranking Scheme.
Current Streamflow, Forecasted Streamflow
Current Streamflow - CO
(USGS)
Colorado
( updated daily )
Current Streamflow - CO
USGS
Current Streamflow Maps
These state maps from USGS show the current (actually the previous day’s) daily streamflow compared to historical streamflows for that gage for day of the year. The color of the circle indicates the percentile ranking of the current daily streamflow among the distribution of historic daily streamflows; see the key below the map thumbnail images. “Low” (red) means the current flow is the record low for that date, while “High” (black) means that the current flow is the record high for that date. The open circles indicate gages that are reporting current flows, but don’t have sufficiently long historic records to be given a percentile ranking.
To access the current flow data for each gage shown on the map, click the “Current Streamflow – XX” header above each thumbnail map, then when that page from USGS loads, mouse-over the gage of interest.
Additional streamflow maps are available from USGS
here
Current Streamflow - UT
(USGS)
Utah
( updated daily )
Current Streamflow - UT
USGS
Current Streamflow Maps
These state maps from USGS show the current (actually the previous day’s) daily streamflow compared to historical streamflows for that gage for day of the year. The color of the circle indicates the percentile ranking of the current daily streamflow among the distribution of historic daily streamflows; see the key below the map thumbnail images. “Low” (red) means the current flow is the record low for that date, while “High” (black) means that the current flow is the record high for that date. The open circles indicate gages that are reporting current flows, but don’t have sufficiently long historic records to be given a percentile ranking.
To access the current flow data for each gage shown on the map, click the “Current Streamflow – XX” header above each thumbnail map, then when that page from USGS loads, mouse-over the gage of interest.
Additional streamflow maps are available from USGS
here
Current Streamflow - WY
(USGS)
Wyoming
( updated daily )
Current Streamflow - WY
USGS
Current Streamflow Maps
These state maps from USGS show the current (actually the previous day’s) daily streamflow compared to historical streamflows for that gage for day of the year. The color of the circle indicates the percentile ranking of the current daily streamflow among the distribution of historic daily streamflows; see the key below the map thumbnail images. “Low” (red) means the current flow is the record low for that date, while “High” (black) means that the current flow is the record high for that date. The open circles indicate gages that are reporting current flows, but don’t have sufficiently long historic records to be given a percentile ranking.
To access the current flow data for each gage shown on the map, click the “Current Streamflow – XX” header above each thumbnail map, then when that page from USGS loads, mouse-over the gage of interest.
Additional streamflow maps are available from USGS
here
Streamflow (last 4 weeks)
(USGS)
( updated daily )
Streamflow (last 4 weeks)
USGS
Current Streamflow Maps
These state maps from USGS show the current (actually the previous day’s) daily streamflow compared to historical streamflows for that gage for day of the year. The color of the circle indicates the percentile ranking of the current daily streamflow among the distribution of historic daily streamflows; see the key below the map thumbnail images. “Low” (red) means the current flow is the record low for that date, while “High” (black) means that the current flow is the record high for that date. The open circles indicate gages that are reporting current flows, but don’t have sufficiently long historic records to be given a percentile ranking.
To access the current flow data for each gage shown on the map, click the “Current Streamflow – XX” header above each thumbnail map, then when that page from USGS loads, mouse-over the gage of interest.
Additional streamflow maps are available from USGS
here
CBRFC Seasonal Streamflow Forecast
( monthly update )
CBRFC Seasonal Streamflow Forecast
NRCS Seasonal Streamflow Forecast
(NRCS)
( monthly update )
NRCS Seasonal Streamflow Forecast
NRCS
Spring-Summer Streamflow Forecast Map
The streamflow forecast map shown from January through May is generated by NRCS, based on their forecasts for one or more forecast points within each basin. The map colors indicate the forecasted spring-summer runoff as a percent of the 1981-2010 normal spring-summer runoff.
Important Note:
Starting in water year 2013, NRCS and NOAA will continue to collaborate on streamflow forecasts, but the forecast values will no longer be strictly coordinated between some of the NOAA NWS River Forecast Centers, including the Colorado Basin River Forecast Center; thus, the NRCS forecast may differ from the NOAA forecast for the same forecast point in the Colorado Basin.)
Forecasts of natural runoff are based principally on observations of precipitation, snow-water equivalent (SWE), and antecedent precipitation in the fall before winter snowfall begins. The forecasts become more accurate as the season progresses and the influences on spring-summer runoff are increasingly captured in the observations. The forecasts earlier in the season assume that climatic factors during the remainder of the snow accumulation and melt season will have an average affect on runoff.
For more information about NRCS streamflow forecasts, go
here
Additional streamflow forecast information:
NOAA streamflow forecasts are available through the following websites of individual River Forecast Centers (RFCs):
Colorado Basin RFC
(also includes Great Basin)
Missouri Basin RFC
(includes South Platte and North Platte)
West Gulf RFC
(includes Rio Grande)
Arkansas Basin RFC
NOAA/NWS River Basin Forecast Centers in the western U.S. have an
interactive website
that shows streamflow forecasts as inputs to reservoirs.
For NRCS State Basin Outlook Reports, visit
here
and select the state from the dropdown menu.
For a monthly summary of snowpack conditions and streamflow forecasts for the western U.S. from the NRCS National Water and Climate Center, visit
here
NRCS Seasonal Streamflow Forecast - Western U.S.
(NRCS)
( monthly update )
NRCS Seasonal Streamflow Forecast - Western U.S.
NRCS
Spring-Summer Streamflow Forecast Map
The streamflow forecast map shown from January through May is generated by NRCS, based on their forecasts for one or more forecast points within each basin. The map colors indicate the forecasted spring-summer runoff as a percent of the 1981-2010 normal spring-summer runoff.
Important Note:
Starting in water year 2013, NRCS and NOAA will continue to collaborate on streamflow forecasts, but the forecast values will no longer be strictly coordinated between some of the NOAA NWS River Forecast Centers, including the Colorado Basin River Forecast Center; thus, the NRCS forecast may differ from the NOAA forecast for the same forecast point in the Colorado Basin.)
Forecasts of natural runoff are based principally on observations of precipitation, snow-water equivalent (SWE), and antecedent precipitation in the fall before winter snowfall begins. The forecasts become more accurate as the season progresses and the influences on spring-summer runoff are increasingly captured in the observations. The forecasts earlier in the season assume that climatic factors during the remainder of the snow accumulation and melt season will have an average affect on runoff.
For more information about NRCS streamflow forecasts, go
here
Additional streamflow forecast information:
NOAA streamflow forecasts are available through the following websites of individual River Forecast Centers (RFCs):
Colorado Basin RFC
(also includes Great Basin)
Missouri Basin RFC
(includes South Platte and North Platte)
West Gulf RFC
(includes Rio Grande)
Arkansas Basin RFC
NOAA/NWS River Basin Forecast Centers in the western U.S. have an
interactive website
that shows streamflow forecasts as inputs to reservoirs.
For NRCS State Basin Outlook Reports, visit
here
and select the state from the dropdown menu.
For a monthly summary of snowpack conditions and streamflow forecasts for the western U.S. from the NRCS National Water and Climate Center, visit
here
Image
Soil Moisture
Surface Soil Moisture Percentiles
( updated weekly )
Surface Soil Moisture Percentiles
Soil Moisture Anomaly
( updated daily )
Soil Moisture Anomaly
Reservoir Storage
Upper Colorado Reservoirs
(Reclamation)
( updated daily )
Upper Colorado Reservoirs
Reclamation
Reservoir ‘Teacup’ Diagrams for Upper Colorado Basin and the Wasatch Front
These diagrams are generated daily by Reclamation based on their latest operational data. The fraction that each tea-cup symbol is filled indicates the current reservoir contents as a fraction of the capacity (i.e., % Full). The size of the teacup is not proportional to the capacity of the reservoir. The first two values provided next to each teacup (e.g., 208746/344800) are the reservoir contents in acre-feet and the capacity in acre-feet, respectively.
Additional reservoir teacup diagrams or operational data for Colorado, Utah, and Wyoming can be accessed as follows:
Great Plains region of Reclamation
(includes Bighorn Basin, Boysen, Buffalo Bill, Colorado-Big Thompson, Fry-Ark, North Platte, Wind River)
Upper Colorado Region of Reclamation
(includes Upper Colorado River Basin, Upper Rio Grande Basin, and nearly all of Utah).
For reservoirs that are not operated by Reclamation (including Bear Lake, Dillon Reservoir, Strawberry Reservoir, and many others), see the
NRCS State Basinwide Reservoir Summaries
(updated monthly).
Wasatch Front Reservoirs
(Reclamation)
( updated daily )
Wasatch Front Reservoirs
Reclamation
Reservoir ‘Teacup’ Diagrams for Upper Colorado Basin and the Wasatch Front
These diagrams are generated daily by Reclamation based on their latest operational data. The fraction that each tea-cup symbol is filled indicates the current reservoir contents as a fraction of the capacity (i.e., % Full). The size of the teacup is not proportional to the capacity of the reservoir. The first two values provided next to each teacup (e.g., 208746/344800) are the reservoir contents in acre-feet and the capacity in acre-feet, respectively.
Additional reservoir teacup diagrams or operational data for Colorado, Utah, and Wyoming can be accessed as follows:
Great Plains region of Reclamation
(includes Bighorn Basin, Boysen, Buffalo Bill, Colorado-Big Thompson, Fry-Ark, North Platte, Wind River)
Upper Colorado Region of Reclamation
(includes Upper Colorado River Basin, Upper Rio Grande Basin, and nearly all of Utah).
For reservoirs that are not operated by Reclamation (including Bear Lake, Dillon Reservoir, Strawberry Reservoir, and many others), see the
NRCS State Basinwide Reservoir Summaries
(updated monthly).
Uinta Basin Reservoirs
(Reclamation)
( updated daily )
Uinta Basin Reservoirs
Reclamation
Reservoir ‘Teacup’ Diagrams for Upper Colorado Basin and the Wasatch Front
These diagrams are generated daily by Reclamation based on their latest operational data. The fraction that each tea-cup symbol is filled indicates the current reservoir contents as a fraction of the capacity (i.e., % Full). The size of the teacup is not proportional to the capacity of the reservoir. The first two values provided next to each teacup (e.g., 208746/344800) are the reservoir contents in acre-feet and the capacity in acre-feet, respectively.
Additional reservoir teacup diagrams or operational data for Colorado, Utah, and Wyoming can be accessed as follows:
Great Plains region of Reclamation
(includes Bighorn Basin, Boysen, Buffalo Bill, Colorado-Big Thompson, Fry-Ark, North Platte, Wind River)
Upper Colorado Region of Reclamation
(includes Upper Colorado River Basin, Upper Rio Grande Basin, and nearly all of Utah).
For reservoirs that are not operated by Reclamation (including Bear Lake, Dillon Reservoir, Strawberry Reservoir, and many others), see the
NRCS State Basinwide Reservoir Summaries
(updated monthly).
Price/San Rafael River Basin Reservoirs
(Reclamation)
Price/San Rafael River Basin Reservoirs
Reclamation
Reservoir ‘Teacup’ Diagrams for Upper Colorado Basin and the Wasatch Front
These diagrams are generated daily by Reclamation based on their latest operational data. The fraction that each tea-cup symbol is filled indicates the current reservoir contents as a fraction of the capacity (i.e., % Full). The size of the teacup is not proportional to the capacity of the reservoir. The first two values provided next to each teacup (e.g., 208746/344800) are the reservoir contents in acre-feet and the capacity in acre-feet, respectively.
Additional reservoir teacup diagrams or operational data for Colorado, Utah, and Wyoming can be accessed as follows:
Great Plains region of Reclamation
(includes Bighorn Basin, Boysen, Buffalo Bill, Colorado-Big Thompson, Fry-Ark, North Platte, Wind River)
Upper Colorado Region of Reclamation
(includes Upper Colorado River Basin, Upper Rio Grande Basin, and nearly all of Utah).
For reservoirs that are not operated by Reclamation (including Bear Lake, Dillon Reservoir, Strawberry Reservoir, and many others), see the
NRCS State Basinwide Reservoir Summaries
(updated monthly).
Upper Green River Basin Reservoirs
(Reclamation)
( updated daily )
Upper Green River Basin Reservoirs
Reclamation
Reservoir ‘Teacup’ Diagrams for Upper Colorado Basin and the Wasatch Front
These diagrams are generated daily by Reclamation based on their latest operational data. The fraction that each tea-cup symbol is filled indicates the current reservoir contents as a fraction of the capacity (i.e., % Full). The size of the teacup is not proportional to the capacity of the reservoir. The first two values provided next to each teacup (e.g., 208746/344800) are the reservoir contents in acre-feet and the capacity in acre-feet, respectively.
Additional reservoir teacup diagrams or operational data for Colorado, Utah, and Wyoming can be accessed as follows:
Great Plains region of Reclamation
(includes Bighorn Basin, Boysen, Buffalo Bill, Colorado-Big Thompson, Fry-Ark, North Platte, Wind River)
Upper Colorado Region of Reclamation
(includes Upper Colorado River Basin, Upper Rio Grande Basin, and nearly all of Utah).
For reservoirs that are not operated by Reclamation (including Bear Lake, Dillon Reservoir, Strawberry Reservoir, and many others), see the
NRCS State Basinwide Reservoir Summaries
(updated monthly).
Gunnison River Basin Reservoirs
(Reclamation)
( updated daily )
Gunnison River Basin Reservoirs
Reclamation
Reservoir ‘Teacup’ Diagrams for Upper Colorado Basin and the Wasatch Front
These diagrams are generated daily by Reclamation based on their latest operational data. The fraction that each tea-cup symbol is filled indicates the current reservoir contents as a fraction of the capacity (i.e., % Full). The size of the teacup is not proportional to the capacity of the reservoir. The first two values provided next to each teacup (e.g., 208746/344800) are the reservoir contents in acre-feet and the capacity in acre-feet, respectively.
Additional reservoir teacup diagrams or operational data for Colorado, Utah, and Wyoming can be accessed as follows:
Great Plains region of Reclamation
(includes Bighorn Basin, Boysen, Buffalo Bill, Colorado-Big Thompson, Fry-Ark, North Platte, Wind River)
Upper Colorado Region of Reclamation
(includes Upper Colorado River Basin, Upper Rio Grande Basin, and nearly all of Utah).
For reservoirs that are not operated by Reclamation (including Bear Lake, Dillon Reservoir, Strawberry Reservoir, and many others), see the
NRCS State Basinwide Reservoir Summaries
(updated monthly).
San Juan River Basin Reservoirs
(Reclamation)
( updated daily )
San Juan River Basin Reservoirs
Reclamation
Reservoir ‘Teacup’ Diagrams for Upper Colorado Basin and the Wasatch Front
These diagrams are generated daily by Reclamation based on their latest operational data. The fraction that each tea-cup symbol is filled indicates the current reservoir contents as a fraction of the capacity (i.e., % Full). The size of the teacup is not proportional to the capacity of the reservoir. The first two values provided next to each teacup (e.g., 208746/344800) are the reservoir contents in acre-feet and the capacity in acre-feet, respectively.
Additional reservoir teacup diagrams or operational data for Colorado, Utah, and Wyoming can be accessed as follows:
Great Plains region of Reclamation
(includes Bighorn Basin, Boysen, Buffalo Bill, Colorado-Big Thompson, Fry-Ark, North Platte, Wind River)
Upper Colorado Region of Reclamation
(includes Upper Colorado River Basin, Upper Rio Grande Basin, and nearly all of Utah).
For reservoirs that are not operated by Reclamation (including Bear Lake, Dillon Reservoir, Strawberry Reservoir, and many others), see the
NRCS State Basinwide Reservoir Summaries
(updated monthly).
Precipitation Forecast
7-Day Precipitation Forecast
(NOAA WPC)
( updated daily )
7-Day Precipitation Forecast
NOAA WPC
Quantitative Precipitation Forecast
Quantitative Precipitation Forecasts (QPFs) are issued by the
Weather Prediction Center (WPC)
and incorporate the latest surface and upper air analyses, radar data, satellite data, and model guidance from the NAM, NGM, GFS and RUC forecast models.  The 5-day QPF map shows the
total
precipitation expected over the 5-day period between the “Valid” and “Thru” dates shown in the lower left corner of the map. The contour intervals (left side) are in inches. Any closed contour with a forecasted value over 1” is marked with an “x”, and the forecasted value is shown on the map. For the
7-Day QPF
, we add to the 5-day product a 48-hour forecast for Days 6-7, which is also prepared by medium-range forecasters. Both forecasts are created twice per day, once at 09Z and again at 21Z.
More information about the QPFs from NOAA WPC is available
here
Seasonal Climate Outlooks
Experimental Winter Precipitation Forecast
( This tool is out of date. A new version will be available soon. )
Experimental Winter Precipitation Forecast
One-Month Precipitation Outlook
(NOAA CPC)
( monthly update )
One-Month Precipitation Outlook
NOAA CPC
Seasonal Precipitation Outlook
The NOAA CPC seasonal precipitation outlooks forecast the likelihood (percent chance) of the 1-month or 3-month temperatures occurring in the above-average, near-average, and below-average categories, based on the historic (1981-2010) distribution of precipitation.  These three categories, or
terciles
, are bounded so that an equal fraction (33.3%) of the historic precipitation values is in each category.
The numeric values on the maps do not refer to actual precipitation values, but to the probability, in percent, that precipitation will be in the
most likely
of these three terciles, if that probability is different than 33.3%. The shading indicates areas in which the odds are tilted towards wetter-than-average (A, green shading) or drier-than-average (B, brown shading) condition. The numeric values indicate the probability that precipitation will be in the above-average or below-average tercile--with a corresponding decrease in the opposite category. The near-average category remains at 33.3% likelihood, unless the forecast probability is very high for the above- or below-average tercile, or a near-average forecast is more likely than the other two categories.
Thus, areas with dark brown shading indicate a 40.0–50.0% chance of below-average, a 33.3% chance of near-average, and a 16.7–26.6% chance of above-average precipitation. Light brown shading displays a 33.3–39.9% chance of below-average, a 33.3% chance of near-average, and a 26.7–33.3% chance of above-average temperatures, and so on. Equal Chances (EC) represents equal odds or a 33.3% probability for each tercile, indicative of areas where forecast signals are weak or conflicting, or the forecast is believed to have poor skill. “N” indicates an increased chance of near-average conditions, but this is not forecast very often.
The skill of the precipitation outlooks largely comes from the status of ENSO.
Additional CPC forecast maps
, at lead times longer than 1.5 months.
Three-Month Precipitation Outlook
(NOAA CPC)
( monthly update )
Three-Month Precipitation Outlook
NOAA CPC
Seasonal Precipitation Outlook
The NOAA CPC seasonal precipitation outlooks forecast the likelihood (percent chance) of the 1-month or 3-month temperatures occurring in the above-average, near-average, and below-average categories, based on the historic (1981-2010) distribution of precipitation.  These three categories, or
terciles
, are bounded so that an equal fraction (33.3%) of the historic precipitation values is in each category.
The numeric values on the maps do not refer to actual precipitation values, but to the probability, in percent, that precipitation will be in the
most likely
of these three terciles, if that probability is different than 33.3%. The shading indicates areas in which the odds are tilted towards wetter-than-average (A, green shading) or drier-than-average (B, brown shading) condition. The numeric values indicate the probability that precipitation will be in the above-average or below-average tercile--with a corresponding decrease in the opposite category. The near-average category remains at 33.3% likelihood, unless the forecast probability is very high for the above- or below-average tercile, or a near-average forecast is more likely than the other two categories.
Thus, areas with dark brown shading indicate a 40.0–50.0% chance of below-average, a 33.3% chance of near-average, and a 16.7–26.6% chance of above-average precipitation. Light brown shading displays a 33.3–39.9% chance of below-average, a 33.3% chance of near-average, and a 26.7–33.3% chance of above-average temperatures, and so on. Equal Chances (EC) represents equal odds or a 33.3% probability for each tercile, indicative of areas where forecast signals are weak or conflicting, or the forecast is believed to have poor skill. “N” indicates an increased chance of near-average conditions, but this is not forecast very often.
The skill of the precipitation outlooks largely comes from the status of ENSO.
Additional CPC forecast maps
, at lead times longer than 1.5 months.
Three-Month Precipitation Outlook (1.5-mo lead)
(NOAA CPC)
( monthly update )
Three-Month Precipitation Outlook (1.5-mo lead)
NOAA CPC
Seasonal Precipitation Outlook
The NOAA CPC seasonal precipitation outlooks forecast the likelihood (percent chance) of the 1-month or 3-month temperatures occurring in the above-average, near-average, and below-average categories, based on the historic (1981-2010) distribution of precipitation.  These three categories, or
terciles
, are bounded so that an equal fraction (33.3%) of the historic precipitation values is in each category.
The numeric values on the maps do not refer to actual precipitation values, but to the probability, in percent, that precipitation will be in the
most likely
of these three terciles, if that probability is different than 33.3%. The shading indicates areas in which the odds are tilted towards wetter-than-average (A, green shading) or drier-than-average (B, brown shading) condition. The numeric values indicate the probability that precipitation will be in the above-average or below-average tercile--with a corresponding decrease in the opposite category. The near-average category remains at 33.3% likelihood, unless the forecast probability is very high for the above- or below-average tercile, or a near-average forecast is more likely than the other two categories.
Thus, areas with dark brown shading indicate a 40.0–50.0% chance of below-average, a 33.3% chance of near-average, and a 16.7–26.6% chance of above-average precipitation. Light brown shading displays a 33.3–39.9% chance of below-average, a 33.3% chance of near-average, and a 26.7–33.3% chance of above-average temperatures, and so on. Equal Chances (EC) represents equal odds or a 33.3% probability for each tercile, indicative of areas where forecast signals are weak or conflicting, or the forecast is believed to have poor skill. “N” indicates an increased chance of near-average conditions, but this is not forecast very often.
The skill of the precipitation outlooks largely comes from the status of ENSO.
Additional CPC forecast maps
, at lead times longer than 1.5 months.
One-Month Temperature Outlook
(NOAA CPC)
( monthly update )
One-Month Temperature Outlook
NOAA CPC
Seasonal Temperature Outlook
The NOAA CPC seasonal temperature outlooks forecast the likelihood (percent chance) of the 1-month or 3-month temperatures occurring in the above-average, near-average, and below-average categories, based on the historic (1981-2010) distribution of temperatures.  These three categories, or
terciles
, are bounded so that an equal fraction (33.3%) of the historic temperatures is in each category.
The numeric values on the maps do not refer to actual temperature values, but to the probability, in percent, that temperatures will be in one of these three terciles, if that probability is different than 33.3%. The shading indicates areas in which the odds are tilted towards warmer-than-average (A, orange shading) or cooler-than-average (B, blue shading) condition. The numeric values indicate the probability that temperatures will be in the above-average or below-average tercile--with a corresponding decrease in the opposite category. The near-average category remains at 33.3% likelihood, unless the forecast probability is very high for the above- or below-average tercile, or a near-average forecast is more likely than the other two categories.
Thus, areas with dark orange shading indicate a 40.0–50.0% chance of below-average, a 33.3% chance of near-average, and a 16.7–26.6% chance of above-average temperatures. Light orange shading displays a 33.3–39.9% chance of below-average, a 33.3% chance of near-average, and a 26.7–33.3% chance of above-average temperatures, and so on. Equal Chances (EC) represents equal odds or a 33.3% probability for each tercile, indicative of areas where forecast signals are weak or conflicting. “N” indicates an increased chance of near-average conditions, but this is not forecast very often.
The skill of the temperature outlooks largely comes from the status of ENSO, and recent warming trends.
Additional CPC forecast maps
, at lead times longer than 1.5 months.
Three-Month Temperature Outlook
(NOAA CPC)
( monthly update )
Three-Month Temperature Outlook
NOAA CPC
Seasonal Temperature Outlook
The NOAA CPC seasonal temperature outlooks forecast the likelihood (percent chance) of the 1-month or 3-month temperatures occurring in the above-average, near-average, and below-average categories, based on the historic (1981-2010) distribution of temperatures.  These three categories, or
terciles
, are bounded so that an equal fraction (33.3%) of the historic temperatures is in each category.
The numeric values on the maps do not refer to actual temperature values, but to the probability, in percent, that temperatures will be in one of these three terciles, if that probability is different than 33.3%. The shading indicates areas in which the odds are tilted towards warmer-than-average (A, orange shading) or cooler-than-average (B, blue shading) condition. The numeric values indicate the probability that temperatures will be in the above-average or below-average tercile--with a corresponding decrease in the opposite category. The near-average category remains at 33.3% likelihood, unless the forecast probability is very high for the above- or below-average tercile, or a near-average forecast is more likely than the other two categories.
Thus, areas with dark orange shading indicate a 40.0–50.0% chance of below-average, a 33.3% chance of near-average, and a 16.7–26.6% chance of above-average temperatures. Light orange shading displays a 33.3–39.9% chance of below-average, a 33.3% chance of near-average, and a 26.7–33.3% chance of above-average temperatures, and so on. Equal Chances (EC) represents equal odds or a 33.3% probability for each tercile, indicative of areas where forecast signals are weak or conflicting. “N” indicates an increased chance of near-average conditions, but this is not forecast very often.
The skill of the temperature outlooks largely comes from the status of ENSO, and recent warming trends.
Additional CPC forecast maps
, at lead times longer than 1.5 months.
Three-Month Temperature Outlook (1.5-mo lead)
(NOAA CPC)
( monthly update )
Three-Month Temperature Outlook (1.5-mo lead)
NOAA CPC
Seasonal Temperature Outlook
The NOAA CPC seasonal temperature outlooks forecast the likelihood (percent chance) of the 1-month or 3-month temperatures occurring in the above-average, near-average, and below-average categories, based on the historic (1981-2010) distribution of temperatures.  These three categories, or
terciles
, are bounded so that an equal fraction (33.3%) of the historic temperatures is in each category.
The numeric values on the maps do not refer to actual temperature values, but to the probability, in percent, that temperatures will be in one of these three terciles, if that probability is different than 33.3%. The shading indicates areas in which the odds are tilted towards warmer-than-average (A, orange shading) or cooler-than-average (B, blue shading) condition. The numeric values indicate the probability that temperatures will be in the above-average or below-average tercile--with a corresponding decrease in the opposite category. The near-average category remains at 33.3% likelihood, unless the forecast probability is very high for the above- or below-average tercile, or a near-average forecast is more likely than the other two categories.
Thus, areas with dark orange shading indicate a 40.0–50.0% chance of below-average, a 33.3% chance of near-average, and a 16.7–26.6% chance of above-average temperatures. Light orange shading displays a 33.3–39.9% chance of below-average, a 33.3% chance of near-average, and a 26.7–33.3% chance of above-average temperatures, and so on. Equal Chances (EC) represents equal odds or a 33.3% probability for each tercile, indicative of areas where forecast signals are weak or conflicting. “N” indicates an increased chance of near-average conditions, but this is not forecast very often.
The skill of the temperature outlooks largely comes from the status of ENSO, and recent warming trends.
Additional CPC forecast maps
, at lead times longer than 1.5 months.
Seasonal Drought Outlook
(NOAA CPC)
( monthly update )
Seasonal Drought Outlook
NOAA CPC
Seasonal Drought Outlook
The Seasonal Drought Outlook (DO) depicts general, large-scale trends from that date through the end of the forecast period (3 to 3.5 months, depending on the date of issue).  The delineated areas in the DO are defined subjectively based on expert assessment of numerous indicators described above, including outputs of short- and long-term forecasting models, as well as consideration of the typical seasonal cycle (it is easier to come out of a drought during the wettest time of year, just as it is easier to worsen a drought situation during that time of year, depending on its moisture anomalies). Areas of continuing drought are approximated from the US Drought Monitor (categories D1 to D4).
Note:
The green areas imply at least a one-category improvement in the Drought Monitor intensity levels, but do not necessarily implythe cessation of drought conditions.
For weekly drought updates, see the
latest Drought Monitor text
(updated weekly).
For more drought information of all kinds, visit the
US Drought Portal.
NOAA NCDC produces
maps of the precipitation anomalies needed to end a drought and the probability of their occurrence
ENSO Conditions and Forecasts
Niño Regions Sea Surface Temps, past 12 months
(IRI)
( updated monthly )
Niño Regions Sea Surface Temps, past 12 months
IRI
Niño 3.4 Sea Surface Temperatures, ENSO Prediction Plume
“Niño 3.4” refers to the region of the equatorial central Pacific from 120°W to 170°W and 5°N to 5°S, which is widely used for monitoring ENSO conditions. The Niño 3.4 SST time-series graph, produced by the International Research Institute for Climate and Society (IRI) at Columbia University, shows monthly SST anomalies in the Niño 3.4 region from January 1982 to present. Values below zero (blue) indicate cooler temperatures, with persistent anomalies below 0.5°C being classified as La Niña (ENSO cold-phase) events. Conversely, values above zero indicate warmer temperatures, with persistent anomalies above 0.5°C being classified as El Niño (ENSO warm-phase) events. The arrow at the far right of the graph indicates the most recent monthly value.
The ENSO Prediction Plume,
also produced by IRI, shows 24 different model forecasts of SST in the Niño 3.4 region for nine overlapping 3-month periods (e.g., OND = October-December) extending 11 months into the future. Differences among the forecasts of the models reflect both differences in model design, and actual uncertainty in the forecast of the possible future SST scenario. The expected skills of the models, based on historical performance, are not equal to one another. The skills also generally decrease as the lead time increases.
For more information about the ENSO forecasts, see the IRI page
here
For a technical discussion of current El Niño conditions, see the
ENSO Diagnostic Discussion
, a collaborative effort of the several parts of NOAA, including the research labs, the IRI, and other institutions funded by NOAA (updated on the second Thursday of the month).
For updated graphics of SST and SST anomalies, visit
here
and click on “Weekly SST Anomalies”:
ENSO Phase Probability
(IRI)
( updated monthly )
ENSO Phase Probability
IRI
Niño 3.4 Sea Surface Temperatures, ENSO Prediction Plume
“Niño 3.4” refers to the region of the equatorial central Pacific from 120°W to 170°W and 5°N to 5°S, which is widely used for monitoring ENSO conditions. The Niño 3.4 SST time-series graph, produced by the International Research Institute for Climate and Society (IRI) at Columbia University, shows monthly SST anomalies in the Niño 3.4 region from January 1982 to present. Values below zero (blue) indicate cooler temperatures, with persistent anomalies below 0.5°C being classified as La Niña (ENSO cold-phase) events. Conversely, values above zero indicate warmer temperatures, with persistent anomalies above 0.5°C being classified as El Niño (ENSO warm-phase) events. The arrow at the far right of the graph indicates the most recent monthly value.
The ENSO Prediction Plume,
also produced by IRI, shows 24 different model forecasts of SST in the Niño 3.4 region for nine overlapping 3-month periods (e.g., OND = October-December) extending 11 months into the future. Differences among the forecasts of the models reflect both differences in model design, and actual uncertainty in the forecast of the possible future SST scenario. The expected skills of the models, based on historical performance, are not equal to one another. The skills also generally decrease as the lead time increases.
For more information about the ENSO forecasts, see the IRI page
here
For a technical discussion of current El Niño conditions, see the
ENSO Diagnostic Discussion
, a collaborative effort of the several parts of NOAA, including the research labs, the IRI, and other institutions funded by NOAA (updated on the second Thursday of the month).
For updated graphics of SST and SST anomalies, visit
here
and click on “Weekly SST Anomalies”:
ENSO Model Projections Plume
(IRI)
( monthly update )
ENSO Model Projections Plume
IRI
Niño 3.4 Sea Surface Temperatures, ENSO Prediction Plume
“Niño 3.4” refers to the region of the equatorial central Pacific from 120°W to 170°W and 5°N to 5°S, which is widely used for monitoring ENSO conditions. The Niño 3.4 SST time-series graph, produced by the International Research Institute for Climate and Society (IRI) at Columbia University, shows monthly SST anomalies in the Niño 3.4 region from January 1982 to present. Values below zero (blue) indicate cooler temperatures, with persistent anomalies below 0.5°C being classified as La Niña (ENSO cold-phase) events. Conversely, values above zero indicate warmer temperatures, with persistent anomalies above 0.5°C being classified as El Niño (ENSO warm-phase) events. The arrow at the far right of the graph indicates the most recent monthly value.
The ENSO Prediction Plume,
also produced by IRI, shows 24 different model forecasts of SST in the Niño 3.4 region for nine overlapping 3-month periods (e.g., OND = October-December) extending 11 months into the future. Differences among the forecasts of the models reflect both differences in model design, and actual uncertainty in the forecast of the possible future SST scenario. The expected skills of the models, based on historical performance, are not equal to one another. The skills also generally decrease as the lead time increases.
For more information about the ENSO forecasts, see the IRI page
here
For a technical discussion of current El Niño conditions, see the
ENSO Diagnostic Discussion
, a collaborative effort of the several parts of NOAA, including the research labs, the IRI, and other institutions funded by NOAA (updated on the second Thursday of the month).
For updated graphics of SST and SST anomalies, visit
here
and click on “Weekly SST Anomalies”:
Latest Briefing
April 9, 2026 - CO, UT, WY
March weather conditions promoted rapid intensification of snow drought. Snowpack peaked three to nine weeks early and sits at record low levels at most locations in Colorado, Utah and much of Wyoming. Record low snowpack was driven by low March precipitation and record hot March temperatures. Consequently, drought conditions expanded to cover 93% of the region, and annual streamflow volume forecasts are much below normal with 22% of normal inflow forecasted for Lake Powell.
March precipitation was below average for nearly the entire region. Large areas of less than 50% of average March precipitation were observed in all three states with the least precipitation falling in eastern Colorado and eastern Wyoming. Record low March precipitation was observed in Baca, Bent, Gunnison, Hinsdale, Las Animas, Prowers, and San Juan Counties in Colorado. Water year precipitation varied with above average precipitation in northwestern Wyoming, southern Colorado and southern Utah, while much of the remainder of the region received 50-90% of average water year precipitation.
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An extreme and widespread heat wave hit the region during March, and temperatures were 9-12 degrees above average for much of the region. Record high March temperatures were observed at the majority of locations in Colorado, Utah and Wyoming. All-time maximum March temperatures were set across the region with many locations recording higher temperatures than all-time April records.
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April 1 SWE conditions were record-low for all regional river basins, except those in northwestern Wyoming. On a statewide basis, record-low snowpack was observed in Colorado (24% median), Utah (22% median), and Wyoming (47% median). Snowpack in many southern Colorado and southern Utah watersheds has melted up to 65 days early, including the Upper Arkansas, Upper Dolores, and Upper Gunnison River basins in Colorado and the Dirty Devil, Escalante, Price, and San Pitch River basins in Utah. Record heat and low precipitation in March caused regional snowpack to peak nearly one month early. Typically, on April 1, only three of 213 Snotel sites in Colorado and two of 179 sites in Utah are melted out completely. On April 1, 2026, 36% of Snotel sites in Colorado, 60% of sites in Utah, and 28% of 196 sites in Wyoming were melted out. The snowpack in the Upper Colorado River basin peaked at a record low percent of median peak SWE and was 27% of median on April 1.
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After low and early peak snowpack, annual streamflow volume forecasts were much below average on April 1. Annual streamflow volume forecasts ranged from 25-45% of average in Colorado, 20-55% of average in Utah and 25-100% of average in Wyoming. The inflow to Lake Powell is forecasted at 22% of average (1.4 million acre-feet). Regional streamflow forecasts were highest in the Snake and Missouri River basins of northern Wyoming where streamflow volume forecasts ranged from 65-100% of average.
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Regional drought intensified during March, and 93% of the region is experiencing severe drought conditions. Extreme drought conditions developed across a broad swath of Utah, western Colorado and southeastern Wyoming, and now cover 45% of the region. Drought in western Colorado worsened by two to three categories, and exceptional drought developed in northwestern Colorado where exceptional drought conditions coincided with the 137,000-acre Lee Fire in August 2025.
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Pacific Ocean temperatures have warmed, and ENSO-neutral conditions (ocean temperatures are within 0.5ºC of average) now exist. Warming sea surface temperatures prompt an 80% probability of ENSO-neutral conditions during April-June, and NOAA issuing an El Niño Watch. ENSO forecasts predict a 60% chance of El Niño conditions developing by May-July and continuing through the end of 2026. There is a 25% chance of a very strong El Niño developing during the beginning of the 2027 water year. NOAA seasonal forecasts for April-June suggest an increased probability for below average precipitation and up to a 70% probability for above average temperatures.
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Significant weather event: March heat wave.
The heat wave during March 2026 was unprecedented in the western U.S. climate records since 1895. March 2026 average temperatures shattered records in Colorado (by 4.3ºF), Utah (by 5.5ºF), and Wyoming (by 2ºF). Amongst weather monitoring sites with at least 50 years of data, new March temperature records were set at 85% of sites in Colorado, 82% of sites in Utah and 60% of sites in Wyoming. In Utah, previous March temperature records were exceeded by 9.7ºF in Alta and 8.9ºF in Escalante. New all-time maximum March temperature records were set at 80-90% of weather sites in Colorado and Utah, and at 70% of sites in Wyoming. At many locations in Colorado and Utah, new March temperature records exceeded April maximum temperature records. Maximum March 2026 temperatures along the Front Range of Colorado reached the 90s with Burlington, CO recording 99ºF on March 26. Extremely high March temperatures were present across the majority of the West, and record statewide March temperatures were set in Arizona, California, Colorado, Idaho, Oklahoma, Nevada, New Mexico, Texas, Utah and Wyoming. A new record March temperature was also set for the contiguous U.S.
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March 12, 2025 - CO, UT, WY
Much of the region experienced its warmest February on record, and Colorado, Utah, and Wyoming ended the season with the warmest December-February on record. As temperatures were much above average throughout the region, precipitation was below to much below average for much of the region, with record-dry conditions along the Front Range, as well as pockets in southeastern Colorado and southern Wyoming. As of March 1, snow drought continues to persist as below to much below normal snow-water equivalent (SWE) was observed for Colorado, Utah, and eastern Wyoming. Seasonal streamflow volume forecasts for regional river basins are below to much below average, except in northern Wyoming where there are near to above average forecasts. Regional drought coverage increased to 76% by early March. The NOAA Seasonal Outlooks for March-May suggest below average precipitation and above average temperatures.
Regional precipitation was below to much below average in February, particularly in northeastern Colorado, with a large pocket of less than 2% of average conditions in Denver, Arapahoe, Adams, Washington, and Weld Counties. Another large pocket of less than 2% of average conditions occurred in southeastern Colorado in Baca County. In contrast, scattered pockets of above average precipitation occurred in each state, with two large pockets of 150-200% of average precipitation in southeastern Colorado and western Wyoming. One small pocket of 200-400% of average precipitation occurred in southeastern Colorado in Kiowa and Bent Counties, and a pocket of 400-800% of average precipitation occurred in western Wyoming in Fremont County. Record-dry February precipitation occurred in many counties along the Front Range in Colorado, including Denver, Boulder, Larimer, Jefferson, Douglas, Adams, Arapahoe, Broomfield, El Paso, Weld, and Park Counties, as well as Baca County in southeastern Colorado. Record-dry conditions also occurred in Carbon and Albany Counties in southern Wyoming, and Tooele County in western Utah.
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Regional temperatures were much above average to record-warm in February. Large swaths of 9 to 12°F above average temperatures occurred in each state, particularly in Wyoming and Colorado, and a large pocket of 12-15°F above average temperatures occurred in southwestern Wyoming. Colorado and Wyoming experienced the warmest February on record, and Utah experienced the third warmest February on record.
All three states experienced the warmest meteorological winter (December-February) on record.
These records are ranked by NOAA NCEI from 1895-2026.
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Below to much below normal snow-water equivalent (SWE) continues in Colorado, Utah, and eastern Wyoming as of March 1. River basins with 50% or less of normal SWE include the Upper Arkansas (45%) in Colorado, and the Lower Colorado-Lake Mead (50%), Upper Colorado-Dirty Devil (47%), Escalante Desert-Sevier Lake (46%), and Lower San Juan (23%) in Utah. In contrast, western Wyoming river basins have near normal SWE, including the Snake Headwaters (96%), Upper Yellowstone (95%), Big Horn (94%), and the Upper Green (91%). Due to record-warm temperatures and below average precipitation for most of the region this winter, snow drought continues to persist.
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Seasonal streamflow volume forecasts for river basins in Colorado, Utah, and southeastern Wyoming are below to much below average. Near to above average seasonal streamflow volumes are forecasted for northern Wyoming. In Colorado, seasonal streamflow forecasts suggest 45-60% of average runoff for all major river basins. Runoff in most major Utah river basins is forecasted at 35-55% of average, except for the Bear River Basin (72%). Wyoming has a mix of streamflow forecasts, with below average forecasts in the Little Snake (46%), North Platte (52%), Cheyenne (57%), Upper Green (64%), and Laramie (69%) River Basins, near average forecasts in the Tongue (93%), Wind (93%), Powder (95%), and Yellowstone (108%) River Basins, and above average forecasts in the Shoshone (113%) and Big Horn (123%) River Basins. Below average inflow is forecasted for many regional reservoirs, including Lake Powell (36%), Navajo (44%), McPhee (47%), Blue Mesa (50%), Guernsey (52%), Deer Creek (53%), Scofield (56%), Deerfield (57%), and Flaming Gorge (64%) Reservoirs.
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Dry and warm conditions during February caused regional drought coverage to increase to 76% by March 3 (drought covered 63% of the region on February 3). Drought conditions especially deteriorated in Wyoming, where moderate (D1) drought coverage increased by 33%, severe (D2) drought coverage increased by 14%, and extreme (D3) drought emerged in southwestern and southeastern Wyoming. In Colorado, D2 drought coverage increased by 11%, and D3 drought coverage increased by 3%, emerging in the Denver Metro region and northwestern Colorado. Utah drought coverage remained the same, with an emergence of D3 drought in northeastern Utah.
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As of mid-February, La Niña conditions are declining and there is a 90% probability of transitioning to ENSO-neutral conditions during March-May. The NOAA March Precipitation Outlook suggests equal chances while the March Temperature Outlook suggests an increased probability of above average temperatures throughout the region. The NOAA Seasonal Precipitation Outlook for March-May suggests an increased probability of below average precipitation in Colorado, Utah, and southern Wyoming, and particularly in the Four Corners region. The NOAA Seasonal Temperature Outlook for March-May suggests an increased probability of above average temperatures in Colorado, Utah, and southern and western Wyoming, and particularly in southern Utah and southwestern Colorado.
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Significant weather event: Extremely warm and dry winter for the Front Range.
Colorado, Utah, and Wyoming experienced the warmest meteorological winter (December-February) on record, and Colorado and Wyoming experienced the warmest February on record. Colorado’s statewide average temperature for December-February was 33.6°F, surpassing the previous record of 32.0°F during the 1980-1981 winter season. Colorado’s Front Range had a particularly warm and dry February, causing extreme (D3) drought to emerge in the Denver Metro region. Denver, Adams, and Arapahoe Counties experienced their driest February on record. Denver experienced its second warmest winter on record, with an average temperature of 39.6°F, just short of the 40.1°F record from the 1933-1934 winter season. For context, the average winter temperature for Denver is 31.9°F, which this winter season significantly exceeds. Denver also experienced its driest winter, with only 13.4 inches of snow recorded by the end of February, well below the average of about 35 inches of snow for December-February. These warm and dry conditions were due to many factors, but the persistent high-pressure ridge that stayed over the western U.S. coupled with La Niña conditions was particularly notable in keeping moisture and cold temperatures out of the region.
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