‘Tale of two snowpacks,’ water report shows elevation matters

Micah Drew

(Daily Montanan) Most sites in Montana hit all-time, or near-record amounts of precipitation in December when an atmospheric river released a deluge across the state.

That’s according to the U.S. Department of Agriculture’s Natural Resources Conservation Service, which released its January Water Supply Outlook Report last week.

Of the 96 SNOTEL stations in Montana, 70 recorded their highest or second-highest December precipitation on record, according to Florence Miller, USDA NRCS hydrologist.

While the precipitation helped improve drought conditions across the state, NRCS data shows a split perspective on how it could impact the state’s water supply for the rest of the year. Higher elevation snow bolstered early-season snowpack, while rain at lower elevations melted out some early snow.

Snowpack is the primary reservoir for water that is released throughout the spring and early summer as it melts out. Low snowpacks can impact streamflows across river basins and lead to major droughts, as was seen in recent years with front-facing impacts such as the low water levels on Flathead Lake.

The first data release for the 2026 water year shows the winter is off to a mixed start — while December brought record precipitation bolstering early season snowpack at high elevations, much of it also fell as rain at lower elevations.

In northwest Montana, the rain led to significant flooding in Lincoln, Sanders and Flathead Counties, leading to state and federal disaster declarations.

All river basins in the state received between 170% and 300% of the 20-year median precipitation for December, according to NRCS data.

“A parade of unseasonably warm storms throughout December meant that although most SNOTEL stations received above normal precipitation, only some of that moisture fell as snow,” the report stated, emphasizing the elevation split meant some SNOTEL sites saw several more inches of snow than normal for the month, while nearby sites a few thousand feet lower saw huge deficits.

“Statewide, snow water equivalent (SWE) is looking deceptively positive,” Miller said.

Snow-water equivalent, rather than snow depth, is the measurement used to gauge the amount of liquid water contained within a 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.

Across the state, snowpack on Jan. 1 ranged from 70% of median to 120% of median, with “most major basins falling at or near normal.”

In the northwest, the Kootenai, Flathead and Upper Clark Fork basins all have snowpacks at more than 100% of median. The upper Yellowstone basin is at 120%, the Bighorn basin at 111%, the Gallatin at 107%, and the Sun-Teton-Marias at 116%.

Lagging behind the state is the Tongue basin, which drains the state’s southeast corner into Wyoming, sitting at 71% of normal.

Another outlier of the early season is the Lower Clark Fork basin, which despite seeing high precipitation during the last three months — including 223% of normal in December — has a snowpack below normal, at just 86% of median. At this time last year, the basin had a snowpack of 112%.

Snowpack in most areas of the state tends to peak in late April.

The NRCS report stated that lower elevation zones that look to have below-average snowpack could see those deficits quickly erased with a few good storm systems.

But the near-term forecast isn’t favoring additional snowfall.

Temperatures across the state Monday and Tuesday look unseasonably warm, with high temperatures in the upper 40s across the western part of the state, and reaching into the 50s in Bozeman and in Billings, according to the National Weather Service.

For a complete look at each river basin’s early-season snowpack conditions, visit the NRCS January report here.