Despite a mix of record high and low temperatures and less than normal precipitation during the month of April, the mountain snowpack is holding strong, according to the USDA’s monthly water supply outlook report. Lucas Zukiewicz, a water supply specialist based in Bozeman, said that stability is a good thing going into the summer.
“(The stability) is beneficial because it keeps more water in the system,” he said.
Snowpack data is calculated using information from SNOWTEL (snow telemetry) sites around the state and it’s useful in determining when the spring runoff might occur.
Overall in Montana, April was dryer than normal and so little snow was added to the snowpack, which could be problematic in some parts of the state, although less so in this area. Cold temperatures earlier in the month — including record lows on April 2 and 12 — combined with an already healthy snowpack means there is still plenty of water in the mountains. That preserved the snowpack so that when warm weather arrived during the third week of April, including one day that set a new record for the average high in many locations, it remained healthy. Zukiewicz said that the Flathead region was not nearly as dry as other parts of the state and thus has an even larger snowpack.
As of May 1, the Columbia River Basin in Montana, which includes the Flathead and Kootenai regions, had 121 percent of its average reservoir storage compared to 115 percent in the Missouri River Basin and 101 percent in the Yellowstone River Basin. The Flathead region had 97 percent of its 30-year average precipitation on May 1 compared to 91 percent in the Lower Clark Fork and 88 percent in the Kootenai.