Intermountain West Climate Dashboard
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The Intermountain West Climate Dashboard provides situational awareness of climate, 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 climate, drought, and water conditions for the Intermountain West are also available from these providers:
- Colorado Climate Center/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
Temperature, Precipitation and Snowpack
Drought Conditions
Current Streamflow, Forecasted Streamflow
Soil Moisture
Reservoir Storage
Precipitation Forecast
Seasonal Climate Outlooks
ENSO Conditions and Forecasts
Latest Briefing
October 8, 2024 - CO, UT, WY
September precipitation was below to much below normal, particularly in Utah and Wyoming where record-dry conditions occurred. Temperatures were above to much above normal, breaking many record-warm temperatures in the region, particularly in Wyoming. Due to below normal precipitation and above normal temperatures in September, regional drought expanded by 7%, now covering 31% of the region. Neutral-ENSO conditions are transitioning into La Niña conditions with a 62% probability forecast that La Niña will develop by early winter. NOAA seasonal forecasts for October-December suggest an increased probability of below average precipitation and above average temperatures for the region.
Regional precipitation during September was below to much below normal, with pockets of above normal precipitation in south-central and southeastern Colorado and northwestern Wyoming. Much below normal precipitation occurred throughout the majority of Utah and Wyoming, with exceptionally below normal (<2%) conditions in southern, western, and eastern Utah, and central Wyoming. Record-dry conditions were scattered throughout Utah and Wyoming with particularly large pockets in Tooele, Kane, and San Juan Counties in Utah.
The region experienced at least 2-4°F above normal temperatures throughout the majority of the region in September, with large areas of 4-6°F above normal temperatures in each state. Pockets of 6-8°F above normal conditions were observed in Utah and Wyoming, with a large swath of these conditions in northeastern Wyoming. The greatest departure from normal temperatures was observed in a pocket of 8-10°F above normal conditions in Weston County, Wyoming. Record-warm temperatures occurred in a staggering amount of Wyoming, particularly in the eastern half of the state, as well as a large pocket from Denver up to Larimer and Weld Counties in Colorado.
The first accumulating snow fell across many mountain locations above 11,000 feet in Colorado on September 4. As of October 1, the highest amount of SWE is at Berthoud Summit in Colorado at 0.3 inches of SWE. Almost all other mountains in the region remain at 0 inches of SWE.
At the end of September, 31% of the region was covered by drought, a 7% expansion since the end of August. Wyoming experienced the most severe drought conditions, with D1 (moderate) drought expanding to 62% and D3 (extreme) drought conditions more than doubling in coverage up to 9% of the state’s area. D1 and D2 (severe) drought conditions both doubled in coverage in Colorado during September. Despite hot and dry conditions, drought coverage in Utah changed little during September.
Streamflow in regional rivers was near to below normal during September. Much below normal streamflow occurred in the New Fork River basin in Wyoming, Big Thompson and Purgatoire River basins in Colorado, and the northern end of the Chinle River basin in Utah. Above normal streamflow occurred in the Wyoming portion of the North Platte River basin, the Upper Laramie River basin in Wyoming, the Colorado portion of the South Platte River basin, and the East Fork Sevier River basin in Utah. Lastly, much above normal streamflow occurred in the Spanish Fork River basin in Utah.
Near-to-below average sea surface temperatures were observed in the eastern Pacific Ocean, consistent with neutral-ENSO conditions. Current forecasts indicate a 62% probability of La Niña developing by December and a 59% probability of neutral-ENSO conditions returning by March. The NOAA monthly precipitation outlook for October suggests an increased probability of below average precipitation for the entire region, with below (50-60%) average conditions for all of Colorado. The monthly temperature outlook suggests an increased probability of above (60-80%) average conditions for the entire region. The NOAA seasonal outlook for October-December suggests an increased probability of below average precipitation for southern Utah and most of Colorado, and above average temperatures for the entire region, particularly in Colorado and Utah, with likely above (60-70%) average conditions in the Four Corners region.
Significant climate event: Late September heat wave. After cooler conditions during mid-September, a significant heat wave settled over the Intermountain West from September 25-30. The six-day period was the hottest on record for many weather monitoring sites with at least 50 years of data. All-time average high temperature records for September 25-30 were set at 28% of long-term weather monitoring sites in Colorado (29 of 105), 38% of sites in Utah (36 of 94), and 43% of sites in Wyoming (34 of 80). The September 25-30 heat was also significant because of the magnitude of heat across the region. The maximum temperatures reached during the heat wave included 104ºF in St. George, UT, 102ºF in Sheridan, WY, and 97ºF in Pueblo, CO, all of which were daily maximum temperature records. Several sites shattered the old all-time average maximum temperature record for September 25-30 including Gillette and Laramie, WY where the previous records were broken by 8.1ºF and 5.5ºF, respectively. During the heat wave, many sites set daily temperature records on multiple days. Across Colorado, Utah, and Wyoming, 17 sites set daily high temperature records on three days, 18 sites set daily temperature records on four days, and 4 sites set daily temperature records on four days. Two sites, Neola, UT, and Grand Junction, CO set daily high temperature records on all six days. Looking back to August predictions of temperature, the NOAA forecast for September correctly forecasted a 70-80% chance of above average temperatures during September. Across North America, a series of late September extreme weather events were interrelated, beginning with an anomalous atmospheric river event in northern British Columbia and southern Alaska which set up a ridging pattern that led to favorable conditions for the late September heat wave and then created conditions that interacted with Hurricane Helene in the southeastern United States.
September 5, 2024 - CO, UT, WY
August precipitation was average to much-above average across the region. Parts of Utah and western Colorado received 2 to 4 times the average August precipitation and it was the wettest August on record for some locations in Colorado. Moisture from the North American monsoon also caused severe thunderstorms and flash flooding, especially in Moab where the August 23rd flood event was the third of the summer. August temperatures were a few degrees above average for most of the region. Drought covers 24% of the region and is most severe in Wyoming where extreme drought conditions developed during August. ENSO-neutral conditions currently exist; a weak La Niña may form during earlier winter, but the majority of winter 2024-2025 will likely see neutral ENSO conditions. September is likely to be drier and warmer than average.
Much of the region received average to much-above average precipitation during August. Large areas of Utah, western Colorado and southwestern Wyoming received 150-400% of average August precipitation. Heavy rains caused record wet August conditions in parts of western Colorado. Record August precipitation was observed in Fruita and Ridgway, CO and Loa and Scofield, UT. August precipitation was 178% of average at Utah SNOTEL sites, 167% at Colorado SNOTEL sites and 138% at Wyoming sites with 12 sites in Utah and 9 sites in Colorado breaking August precipitation records. As of September 1st, water year precipitation is 108% of average in Colorado, 139% of average in Utah and 115% of average in Wyoming.
August temperatures were up to two degrees above average across most of the region. In eastern Colorado and southeastern Wyoming, August temperatures were 2 to 4 degrees above average and record hot conditions were recorded in parts of the Front Range.
August monthly streamflow was near-normal for most of Utah and western Colorado river basins. Below average monthly streamflow was observed in parts of the Arkansas, Blue, Clear Creek, Colorado, Fraser and South Platte River Basins in Colorado. In Wyoming, August streamflow was below the 5th percentile in parts of the Snake and Wind River Basins. Regional reservoir storage remains above normal in Utah (114% of median capacity) and near-normal in Colorado (93% median capacity) and Wyoming (95% median capacity).
At the end of August, 24% of the region was covered by drought. While total regional coverage of drought changed little in August, drought conditions generally worsened in Wyoming and improved along the northern Front Range of Colorado. In Wyoming, coverage of D1 drought expanded, D2 drought developed in northwestern Wyoming and D3 drought developed in northeastern Wyoming. Drought conditions were removed from parts of the northern Front Range and southeastern Wyoming during August. In Utah, a small area of D1 drought developed near St. George.
Sea surface temperatures in the eastern Pacific Ocean are near average and consistent with ENSO-neutral conditions. Current ENSO forecasts suggest that a weak La Niña may develop in early winter, but that ENSO-neutral conditions are likely to dominate during winter 2024-2025. During both September and September - November, there is an increased probability of below average precipitation for the entire region. There is an increased probability of above average temperatures for the entire region during September – November including a 60-70% probability of above average temperatures during September.
August weather event. More flash flooding in Moab. A significant flash flood tore through Mill Creek in downtown Moab for the third time this summer. In the early evening of August 23rd, a line of severe thunderstorms passed through Moab and the La Sal Mountains, dropping 0.1-1.1” of rain in less than 30 minutes. Despite the modest rainfall amount, the rapid rainfall rate caused severe flash flooding. Mill Creek, which typically flows through downtown Moab at 5 cubic feet per second (cfs) during summer. At 8:15 pm, approximately two hours after the rain event, Mill Creek flow peaked at 6,660 cfs. Debris caught on bridges over Mill Creek caused water to back up and flow through Main Street in Moab and severely damaged one bridge. The August 23rd flash flood event marks the third time this summer that heavy rainfall has caused severe flooding in Moab. On 6/21, heavy rainfall caused severe flooding in Moab due to a flash flooding Mill Creek which had a peak flow of 5,080 cfs. On 6/27, another round of heavy rainfall on the north side of Moab caused flooding primarily due to rapid rainfall rates and surface runoff. Since the August 23rd flood event, Utah Governor Spencer Cox declared a state of emergency in Moab.
