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Colorado River Basin

Colorado River Basin Current Conditions

Drought & Dryness Categories
Value Map Hex Color % of Colorado River Basin Description
D0 – Abnormally Dry #ffff00 0 Abnormally Dry Abnormally Dry (D0) indicates a region that is going into or coming out of drought. 
D1 – Moderate Drought #ffcc99 0 Moderate Drought Moderate Drought (D1) is the first of four drought categories (D1–D4), according to the U.S. Drought Monitor.
D2 – Severe Drought #ff6600 0 Severe Drought Severe Drought (D2) is the second of four drought categories (D1–D4), according to the U.S. Drought Monitor. 
D3 – Extreme Drought #ff0000 0 Extreme Drought Extreme Drought (D3) is the third of four drought categories (D1–D4), according to the U.S. Drought Monitor.
D4 – Exceptional Drought #660000 0 Exceptional Drought Exceptional Drought (D4) is the most intense drought category, according to the U.S. Drought Monitor. 
Total Area in Drought (D1–D4) dmtotal 0 Total Area in Drought (D1–D4) Percent area of this watershed that is currently in drought (D1–D4), according to the U.S. Drought Monitor.
Percent of Normal Precipitation (%)
Range Map Hex Color Description
0% - 25% #8c510a Precipitation was only 0% to 25% of the historical average for this location, compared to the same date range from 1991–2020. 
25% - 50% #bf812d 25%–50% of Normal Precipitation was 25% to 50% of the historical average for this location, compared to the same date range from 1991–2020. 
50% - 75% #dfc27d 50%–75% of Normal Precipitation was 50% to 75% of the historical average for this location, compared to the same date range from 1991–2020. 
75% - 100% #f6e8c3 75%–100% of Normal Precipitation was 75% to 100% of the historical average for this location, compared to the same date range from 1991–2020. 
Range Map Hex Color Description
100% - 150% #c7eae5 100%–150% of Normal Precipitation was 100% to 150% of the historical average for this location, compared to the same date range from 1991–2020. 
150% - 200% #80cdc1 150%–200% of Normal Precipitation was 150% to 200% of the historical average for this location, compared to the same date range from 1991–2020. 
200% - 300% #35978f 200%–300% of Normal Precipitation was 200% to 300% of the historical average for this location, compared to the same date range from 1991–2020. 
300% - #01665e >300% of Normal Precipitation was greater than 300% of the historical average for this location, compared to the same date range from 1991–2020. 
Departure from Normal Max Temperature (°F)
Range Map Hex Color Description
- -8 #0404ff >8°F Below Normal The average maximum temperature was more than 8°F colder than normal for this location.
-8 - -6 #2166ac 6–8°F Below Normal The average maximum temperature was 6–8°F colder than normal for this location.
-6 - -4 #4393c3 4–6°F Below Normal The average maximum temperature was 4–6°F colder than normal for this location.
-4 - -3 #92c5de 3–4°F Below Normal The average maximum temperature was 3–4°F colder than normal for this location.
-3 - -1 #d1e5f0 1–3°F Below Normal The average maximum temperature was 1–3°F colder than normal for this location.
-1 - 0 #ffffff 0–1°F Below Normal The average maximum temperature was 0–1°F colder than normal for this location.
Range Map Hex Color Description
0 - 1 #ffffff 0–1°F Above Normal The average maximum temperature was 0–1°F warmer than normal for this location.
1 - 3 #fddbc7 1–3°F Above Normal The average maximum temperature was 1–3°F warmer than normal for this location.
3 - 4 #f4a582 3–4°F Above Normal The average maximum temperature was 3–4°F warmer than normal for this location.
4 - 6 #d6604d 4–6°F Above Normal The average maximum temperature was 4–6°F warmer than normal for this location.
6 - 8 #b2182b 6–8°F Above Normal The average maximum temperature was 6–8°F warmer than normal for this location.
8 - #800000 >8°F Above Normal The average maximum temperature was more than 8°F warmer than normal for this location.

Multi-Indicator Drought Index (MIDI)

Dry Conditions
Value Map Hex Color Description
D4 #730000 Exceptional Drought (0–2nd Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 98% to 100% of past conditions. Learn more about these categories.
D3 #E60000 Extreme Drought (2nd–5th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 95% to 98% of past conditions. Learn more about these categories.
D2 #FFAA00 Severe Drought (5th–10th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 90% to 95% of past conditions. Learn more about these categories.
D1 #FCD37F Moderate Drought (10th–20th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 80% to 90% of past conditions. Learn more about these categories.
D0 #FFFF00 Abnormally Dry (20th–30th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 70% to 80% of past conditions. Learn more about these categories.
Wet Conditions
Value Map Hex Color Description
W0 #AAFF55 Abnormally Wet (70th–80th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 70% to 80% of past conditions. Learn more about these categories.
W1 #01FFFF Moderate Wet (80th–90th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 80% to 90% of past conditions. Learn more about these categories.
W2 #00AAFF Severe Wet (90th–95th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 90% to 95% of past conditions. Learn more about these categories.
W3 #0000FF Extreme Wet (95th–98th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 95% to 98% of past conditions. Learn more about these categories.
W4 #0000AA Exceptional Wet (98th–100th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 98% to 100% of past conditions. Learn more about these categories.

Experimental

Dry Conditions
Value Map Hex Color Description
D4 #730000 Exceptional Drought (0–2nd Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 98% to 100% of past conditions. Learn more about these categories.
D3 #E60000 Extreme Drought (2nd–5th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 95% to 98% of past conditions. Learn more about these categories.
D2 #FFAA00 Severe Drought (5th–10th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 90% to 95% of past conditions. Learn more about these categories.
D1 #FCD37F Moderate Drought (10th–20th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 80% to 90% of past conditions. Learn more about these categories.
D0 #FFFF00 Abnormally Dry (20th–30th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are drier than 70% to 80% of past conditions. Learn more about these categories.
Wet Conditions
Value Map Hex Color Description
W0 #AAFF55 Abnormally Wet (70th–80th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 70% to 80% of past conditions. Learn more about these categories.
W1 #01FFFF Moderate Wet (80th–90th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 80% to 90% of past conditions. Learn more about these categories.
W2 #00AAFF Severe Wet (90th–95th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 90% to 95% of past conditions. Learn more about these categories.
W3 #0000FF Extreme Wet (95th–98th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 95% to 98% of past conditions. Learn more about these categories.
W4 #0000AA Exceptional Wet (98th–100th Percentile) This map integrates multiple drought indices measuring precipitation and moisture into one computer-generated drought map, with a reference period of 1979–present. According to these indices, current conditions are wetter than 98% to 100% of past conditions. Learn more about these categories.

Experimental
Agriculture in Colorado River Basin

U.S. Drought Monitor
Value Map Hex Color Description
D0 #ffff00 D0 - Abnormally Dry Abnormally Dry (D0) indicates a region that is going into or coming out of drought, according to the U.S. Drought Monitor. View typical impacts by state.
D1 #fcd37f D1 – Moderate Drought Moderate Drought (D1) is the first of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D2 #fa0 D2 – Severe Drought Severe Drought (D2) is the second of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D3 #e60000 D3 – Extreme Drought Extreme Drought (D3) is the third of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D4 #730000 D4 – Exceptional Drought Exceptional Drought (D4) is the most intense drought category, according to the U.S. Drought Monitor. View typical impacts by state.
U.S. Drought Monitor
Value Map Hex Color Description
D0 #ffff00 D0 - Abnormally Dry Abnormally Dry (D0) indicates a region that is going into or coming out of drought, according to the U.S. Drought Monitor. View typical impacts by state.
D1 #fcd37f D1 – Moderate Drought Moderate Drought (D1) is the first of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D2 #fa0 D2 – Severe Drought Severe Drought (D2) is the second of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D3 #e60000 D3 – Extreme Drought Extreme Drought (D3) is the third of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D4 #730000 D4 – Exceptional Drought Exceptional Drought (D4) is the most intense drought category, according to the U.S. Drought Monitor. View typical impacts by state.
U.S. Drought Monitor
Value Map Hex Color Description
D0 #ffff00 D0 - Abnormally Dry Abnormally Dry (D0) indicates a region that is going into or coming out of drought, according to the U.S. Drought Monitor. View typical impacts by state.
D1 #fcd37f D1 – Moderate Drought Moderate Drought (D1) is the first of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D2 #fa0 D2 – Severe Drought Severe Drought (D2) is the second of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D3 #e60000 D3 – Extreme Drought Extreme Drought (D3) is the third of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D4 #730000 D4 – Exceptional Drought Exceptional Drought (D4) is the most intense drought category, according to the U.S. Drought Monitor. View typical impacts by state.
U.S. Drought Monitor
Value Map Hex Color Description
D0 #ffff00 D0 - Abnormally Dry Abnormally Dry (D0) indicates a region that is going into or coming out of drought, according to the U.S. Drought Monitor. View typical impacts by state.
D1 #fcd37f D1 – Moderate Drought Moderate Drought (D1) is the first of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D2 #fa0 D2 – Severe Drought Severe Drought (D2) is the second of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D3 #e60000 D3 – Extreme Drought Extreme Drought (D3) is the third of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D4 #730000 D4 – Exceptional Drought Exceptional Drought (D4) is the most intense drought category, according to the U.S. Drought Monitor. View typical impacts by state.
U.S. Drought Monitor
Value Map Hex Color Description
D0 #ffff00 D0 - Abnormally Dry Abnormally Dry (D0) indicates a region that is going into or coming out of drought, according to the U.S. Drought Monitor. View typical impacts by state.
D1 #fcd37f D1 – Moderate Drought Moderate Drought (D1) is the first of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D2 #fa0 D2 – Severe Drought Severe Drought (D2) is the second of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D3 #e60000 D3 – Extreme Drought Extreme Drought (D3) is the third of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D4 #730000 D4 – Exceptional Drought Exceptional Drought (D4) is the most intense drought category, according to the U.S. Drought Monitor. View typical impacts by state.

Crop Production (Acres) or Livestock Count

A circle with the radius of 20 pixels identifies:
> 500,000
A circle with the radius of 16 pixels identifies:
> 300,000
A circle with the radius of 12 pixels identifies:
> 100,000
A circle with the radius of 8 pixels identifies:
≤ 100,000

{{AG_STAT_1}}
{{AG_DESC_1}} (estimated) in drought (D1–D4)
{{AG_STAT_2}}
{{AG_DESC_2}} (estimated) in drought (D1–D4)
{{AG_STAT_3}}
{{AG_DESC_3}} (estimated) in drought (D1–D4)
{{AG_STAT_4}}
{{AG_DESC_4}} (estimated) in drought (D1–D4)
{{AG_STAT_5}}
{{AG_DESC_5}} (estimated) in drought (D1–D4)
Water Supply in Colorado River Basin

Streamflow Conditions
Value Map Hex Color Description
Low #ff0000 Record Low Estimated streamflow is the lowest value recorded at this gauge on this day of the year. Learn more.
Much Below #b12121 Much Below Normal ( Estimated streamflow is in the 0–10th percentile of historical streamflow values recorded at this gauge on this day of the year. Learn more.
Below #ffa400 Below Normal (10th–25th Percentile) Estimated streamflow is in the 10th–25th percentile of historical streamflow values recorded at this gauge on this day of the year. Learn more.
Normal #00ff00 Normal (25th–75th Percentile) Estimated streamflow is in the 25th–75th percentile of historical streamflow values recorded at this gauge on this day of the year. Learn more.
Value Map Hex Color Description
Above #40dfd0 Above Normal (75th–90th Percentile) Estimated streamflow is in the 75th–90th percentile of historical streamflow values recorded at this gauge on this day of the year. Learn more.
Much Above #0000ff Much Above Normal (>90th Percentile) Estimated streamflow is in the 90th–100th percentile of historical streamflow values recorded at this gauge on this day of the year. Learn more.
High #000000 Record High Estimated streamflow is the highest value ever measured at this gauge on this day of the year. Learn more.
Not Ranked #ffffff Not Ranked A flow category has not been computed for this gauge, for example due to insufficient historical data or no current streamflow estimates.
Probability of Below-Normal Precipitation
Range Map Hex Color Description
33% - 40% #f0d493 33%–40% Chance of Below Normal There is an 33%–40% chance of below-normal precipitation during this period. 
40% - 50% #d8a750 40%–50% Chance of Below Normal There is an 40%–50% chance of below-normal precipitation during this period. 
50% - 60% #bb6d33 50%–60% Chance of Below Normal There is an 50%–60% chance of below-normal precipitation during this period. 
60% - 70% #9b5031 60%–70% Chance of Below Normal There is an 60%–70% chance of below-normal precipitation during this period. 
70% - 80% #934639 70%–80% Chance of Below Normal There is an 70%–80% chance of below-normal precipitation during this period. 
80% - 90% #804000 80%–90% Chance of Below Normal There is an 80%–90% chance of below-normal precipitation during this period. 
90% - 100% #4f2f2f >90% Chance of Below Normal There is a >90% chance of below-normal precipitation during this period. 
Probability of Above-Normal Precipitation
Range Map Hex Color Description
33% - 40% #b3d9ab 33%–40% Chance of Above Normal There is an 33%–40% chance of above-normal precipitation during this period. 
40% - 50% #94cd7e 40%–50% Chance of Above Normal There is an 40%–50% chance of above-normal precipitation during this period. 
50% - 60% #48ae38 50%–60% Chance of Above Normal There is an 50%–60% chance of above-normal precipitation during this period. 
60% - 70% #3a7b5f 60%–70% Chance of Above Normal There is an 60%–70% chance of above-normal precipitation during this period. 
70% - 80% #008e40 70%–80% Chance of Above Normal There is an 70%–80% chance of above-normal precipitation during this period. 
80% - 90% #28553d 80%–90% Chance of Above Normal There is an 80%–90% chance of above-normal precipitation during this period. 
90% - 100% #285517 >90% Chance of Above Normal There is a >90% chance of above-normal precipitation during this period. 
Probability of Near-Normal Precipitation
Range Map Hex Color Description
33% - 40% #d7d7d7 33%–40% of Near Normal There is an 33%–40% chance of near-normal precipitation during this period. 
40% - 50% #a2a2a2 40%–50% of Near Normal There is an 40%–50% chance of near-normal precipitation during this period. 

{{WS_STAT_1}}
percent of streamflow sites are below normal
{{WS_STAT_2}}
percent of streamflow sites are above normal
{{WS_STAT_3}}
percent of the Colorado River Basin has below-normal precipitation probability this month
{{WS_STAT_4}}
percent of the Colorado River Basin has above-normal precipitation probability this month

Historical Conditions for the Colorado River Basin

U.S. Drought Monitor
Value Map Hex Color Description
D0 #ffff00 D0 - Abnormally Dry Abnormally Dry (D0) indicates a region that is going into or coming out of drought, according to the U.S. Drought Monitor. View typical impacts by state.
D1 #fcd37f D1 – Moderate Drought Moderate Drought (D1) is the first of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D2 #fa0 D2 – Severe Drought Severe Drought (D2) is the second of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D3 #e60000 D3 – Extreme Drought Extreme Drought (D3) is the third of four drought categories (D1–D4), according to the U.S. Drought Monitor. View typical impacts by state.
D4 #730000 D4 – Exceptional Drought Exceptional Drought (D4) is the most intense drought category, according to the U.S. Drought Monitor. View typical impacts by state.

The U.S. Drought Monitor (2000–present) depicts the location and intensity of drought across the country. Every Thursday, authors from NOAA, USDA, and the National Drought Mitigation Center produce a new map based on their assessments of the best available data and input from local observers. The map uses five categories: Abnormally Dry (D0), showing areas that may be going into or are coming out of drought, and four levels of drought (D1–D4). Learn more.

Drought in the Colorado River Basin

Reliance on Colorado River Water Resources

The Colorado River provides water to almost 40 million people in two countries, seven states, 29 federally recognized Indian tribes, and 4 million acres of farmland. According to a University of Arizona study, the Colorado River supports $1.4 trillion in annual economic activityequivalent to 1/12th of total U.S. gross domestic productand 16 million jobs in Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming. Since 2000, historically dry conditions have added stress to the Colorado River’s already over-allocated water resources.

Story Map: Drought in the Colorado River Basin

Since 2000, the Colorado River basin has been experiencing a historic, extended drought that has impacted regional water supply and other resources, such as hydropower, recreation, and ecological goods and services services.

Learn more about the current 16-year drought and its effects on the Colorado River basin through this story map, which was created by the U.S. Geological Survey and the Bureau of Reclamation.

Colorado Basin River Forecast Center

View river, snow, and reservoir conditions; forecasts of temperature, precipitation, water supply and peak flows; soil moisture conditions and other data, maps, and tools for the Colorado River through the National Weather Service Colorado Basin River Forecast Center (CBRFC).

The CBRFC is responsible for monitoring and forecasting climate conditions for the entire Colorado River basin and the Great Basin, covering an area of 303,450 square miles.

Colorado River Interim Guidelines and the Drought Contingency Plan

Since 2008, Lake Mead and Lake Powell have been operated in accordance with the 2007 Record of Decision for the Colorado River Interim Guidelines for Lower Basin Shortages and the Coordinated Operations for Lake Powell and Lake Mead. The Guidelines define operating procedures during drought and low reservoir conditions to minimize shortages in the Lower Colorado basin and avoid the risk of curtailment in the Upper Colorado basin. These Guidelines remain in effect through 2025. In advance of negotiating new Guidelines, in 2020 the U.S. Bureau of Reclamation issued a report on an assessment of effectiveness of the Guidelines. A key conclusion of the report was that “increasing severity of the drought necessitated additional action to reduce the risk of reaching critically low elevations in Lakes Powell and Mead.”

In addition, to reduce the risk of Lake Powell and Lake Mead declining to critically low levels, in December 2017, the U.S. Department of the Interior called on the seven Colorado River basin states to put drought contingency plans in place before the end of 2018. Congress approved the plan submitted by the states of Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming as the Colorado River Drought Contingency Plan Authorization Act on April 16, 2019.

Lake Mead showing low water levels