Major Change in Weather Patterns During February Benefits Montana’s Snowpack

Shucking expectations of continued above average temperatures and below normal snowfall, February delivered abundant snowfall and December-like temperatures to the Treasure State. Snowfall for the month was above normal to record setting across the state, and snowpack totals for March 1 have improved in all river basins, according to snow survey data collected by the USDA Natural Resources Conservation Service (NRCS)    

February began with an active weather pattern that dropped significant snowfall across the state and persisted through the month. “Unlike the traditional proverb, February came in like a lion and went out like a lion,” said Lucas Zukiewicz, water supply specialist for the USDA NRCS. Consistent snowfall in almost all the ranges of Montana helped to make up some of the early season snowfall deficits we had in some river basins. “It seemed like every time a storm was moving out another one was lined up to come in,” said Zukiewicz. 

Monthly totals were especially impressive in some southern and central regions of Montana. While all regions of the state received above normal snowfall, storm patterns through the month favored areas in the southern part of the state where storms approaching from the southwest can drop significant snowfall. “This month was the perfect setup with cold air in place and abundant moisture coming from the Pacific that collided with it,” said Zukiewicz. “Sixteen NRCS snowpack measurement locations set new records for February snowfall in central and southern Montana, and an additional 13 sites recorded the second highest monthly totals.”

The abundant February snowfall alleviated concern over areas that had below normal snowpack last month.  Snowpack totals have improved to near normal in many northern river basins, and to well above normal in basins in southern Montana. “There are still a few places in the state that are below normal for snowpack, and streamflow forecasts in these regions reflect the lack of fall precipitation and below normal snowpack on March 1,” said Zukiewicz.

Streamflow forecasts issued on March 1 for April 1 – July 31 indicate near to above average seasonal volumes in many areas across southern Montana but are slightly below average in some northern basins due to the early season deficits that remain in water year-to-date precipitation. Water users are encouraged to look at their river basin of interest for the individual point forecasts, which can vary widely within a major river basin. 

While improved snowpack totals and above normal totals in certain rivers basins is good news for this date, there is still plenty of winter and spring left to come. Snowpack in the state typically peaks in early April west of the Divide and in mid to late April east of the Divide. “We have another month or two of snow accumulation to go, and it can be an important couple of months to top things off before we start to see snowmelt and runoff. We’re back on the right track, so let’s hope that the snow keeps flying and the above average temperatures don’t show back up before then,” said Zukiewicz.

The March 1, 2019 Monthly Water Supply Outlook Report is also available.