The snowpack across most of the western U.S. isn’t looking good in most states, but it’s a different story in the state of Montana, according to snowpack data collected by the USDA Natural Resources Conservation Service (NRCS).
After a hot and dry summer, snowfall began at the end of September in the Treasure State, helping to alleviate fire concerns and beginning the seasonal snowpack at high elevations. Many basins began the new 2018 water year (starting Oct. 1) with at least some snow on the ground at the higher elevations, and most basins had snow at all elevations by the beginning of November. Consistent snowfall statewide during November increased snowpack totals through the third week of the month, before a warm and dry period near the holiday melted some low elevation snow and slowed mountain accumulation. The early December lull in snowfall lasted through the middle of the month before the pattern made a major change.
The latter half of December brought substantial snowfall across the state, and helped many basins improve from below normal in mid-December to near to well above normal on Jan. 1. During that same time, SNOTEL sites west of the Divide received up to 10.9 inches of snow water equivalent from storms, raising basin percentages in all western basins. While the most recent storm favored basins west of the Divide, basins east of the Divide also received up to 7.5 inches of snow water in south central basins.
“The snowpack in Montana is off to a great start across the state, and it’s nice to brag about it, but it’s really important to remember that there is a lot of winter left to come,” said Lucas Zukiewicz, NRCS water supply specialist for Montana. He said typically, by this time of the year, about 40 to 50 percent of the seasonal snowpack has accumulated west of the Divide and 30 to 40 percent of the snowpack has accumulated east of the Divide.
“Really, it’s the April 1 and May 1 snow totals that mean the most for water users in Montana. By then we should have a better idea of the amount of water being stored in the statewide snowpack, and how that will impact water users during the spring and summer,” said Zukiewicz. Looking forward, Zukiewicz said the early spring months are critical when it comes to snowfall and water supply in the state, and continued consistent snowfall could put water users in a great position come the spring when the snowmelt begins. Only time will tell, he continued.
Monthly Water Supply Outlook Reports can be found HERE.
|1/1/2018||Percent of Normal||Percent of Last Year|
|Columbia River Basin||126||142|
|Upper Clark Fork||154||188|
|Lower Clark Fork||116||135|
|Missouri River Basin||126||158|
|Yellowstone River Basin||145||133|
|West of the Divide||126||142|
|East of the Divide||133||140|
|1/1/2018||Monthly Percent Average||Water Year Percent Average||Water Year Percent Last Year|
|Columbia River Basin||123||119||94|
|Upper Clark Fork||150||127||117|
|Lower Clark Fork||115||117||92|
|Missouri River Basin||118||112||85|
|Yellowstone River Basin||135||118||86|
|West of the Divide||123||119||94|
|East of the Divide||123||115||87|