14-05-2025
Montana snowpack near normal for most regions
The Jefferson River near Cardwell, Montana, on June 19, 2024. (Photo by Blair Miller, Daily Montanan)
As Montana moves towards warmer weather, scientists with the U.S. Department of Agriculture continue to monitor the status of the state's snowpack and forecast how the waterways will flow this summer. But, much of the state appears to be better shape than the same time last year.
Most sites in Montana have passed their peak snow water equivalent accumulation for the season, with a majority of sites reaching near to below normal peak snowpack.
That's according to the U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS), which released its May Water Supply Outlook Report last week.
'The shift to spring brought to a close the bulk of the snowpack accumulation season and started the snowmelt and runoff season,' said Florence Millers, a NRCS hydrologist, in a press release about the report.
Weather in April was slightly warmer than normal for much of the state, while precipitation varied. Across the southwest and central Montana, precipitation for the year is near normal, while in the Northwest, an early water deficit has not been overcome, and the region is between 75-90% of median precipitation.
'Several April warm spells that brought periods of above normal temperatures and initiated snowmelt across many low-to mid-elevation SNOTEL sites,' Miller said.
As of May 1, snowpack percentages in the southwest and central parts of the state range between 95-110% of median, while snowpack in the western portion of the state has decreased to between 75-90% of median. The Sun-Teton-Marias basis saw 'well below normal' snowpack throughout the winter and is at just 61% of median snow water equivalent.
Snow-water equivalent, rather than snow depth, is the measurement used to gauge the amount of liquid water contained within snowpack, which will be released when the snowpack melts. The snowmelt plays a key role in agriculture, hydropower production, water storage, aquatic ecosystem health and recreation such as boating and fishing, as well as flood and drought forecasting.
The May water supply report highlights that while some early season melt has already occurred at some monitoring sites across the state, 'there is still a lot of water stored within the higher elevation snowpacks' and weather in the coming weeks will shape the water supply for the summer.
In April, the Beartooth and Bighorn mountains saw roughly double their normal precipitation for the month, much of it as snow, bolstering water supply in the regions. The Flathead and Kootenai basins also saw much more precipitation than average, which could benefit Flathead Lake in the early summer months.
The Tongue River Basin in the Bighorn Mountains has the highest snowpack compared to the 20-year median, according to NRCS data, at 111%. Meanwhile the Sun-Teton-Marias basin measured just 61% of median as of May 1.
Despite relatively good conditions throughout April, much of Montana is under drought conditions, according to the U.S. Drought Monitor.
Nearly three-quarters of the state is under some level of drought conditions, which range from 'abnormally dry' to 'exceptional drought.'
More than 43% of the state is under 'moderate drought' conditions, while a portion of the Upper Clark Fork and Blackfoot basins are classified as 'severe to extreme drought.'
The water supply forecast currently predicts much of state the will be near or below normal, ranging from 70-110% of median. At the low end of that prediction scale is the Powder River basin, currently forecast at between 60-70% of normal.
The Flathead River Basin is at 86% of median snowpack, compared to 68% at this time last year. Streamflows on the main Flathead River are forecast around 80% of the 20-year average.
The Upper Clark Fork Basin is sitting at 91% of median snowpack, a significant improvement from last year when it has just 56% of normal.
The Madison River Basin has a snowpack at 86% of normal, higher than at this point last year and is forecast to have streamflows around 85% of normal.
The Upper Missouri River Basin had a May 1 snowpack of 74% of median, significantly higher than the 42% seen in 2024.
For a complete look at each river basin's snowpack conditions and streamflow forecast, visit the NRCS May report here.
Flathead Lake, the largest freshwater lake west of the Mississippi River, has become a contentious point for water policy debates following extreme drought in 2023 that saw the lake fill to less than two feet below normal.
During the 2025 Legislative session, Montana lawmakers passed a resolution supporting recreational uses on Flathead Lake to be considered during management discussion by the myriad local, state, tribal and federal partners that coordinate the lake's water level.
Energy Keepers Inc., the Confederated Salish and Kootenai Tribes company that operates the Se̓liš Ksanka Qĺispe̓ Dam on the south end of the lake, published regular updates using the latest streamflow predictions to inform the public of where it expects the lake levels to be.
According to a May 13 update, Energy Keepers expects the lake to reach its full-pool elevation of 2,893 feet by early to mid-June.
So far, the SKQ project has not had to coordinate flood risk management changes to its operating plan, as it has done the last two years when streamflow forecasts were much lower than normal.
The latest update from Energy Keepers states that while expectations are for the lake to fill to normal levels, 'both weather and streamflows are highly uncertain.'
'SKQ Project outflows and the Flathead Lake elevation are dependent on many variables including lake inflows, weather, the demand for electricity, and non-power constraints such as the downstream fishery and flood risk management needs.'
