Low snowfall could leave Bozeman’s “natural water tower” dry

Bozeman has seen a total of 46.2 inches of snowfall through the end of Feb. 2024,  according to NOAA online weather data. Though this February's snowfall of 17.3 inches was greater than last February’s snowfall of 13.5 inches, the total snowfall for the season so far still falls almost 30 inches behind last year's mark of 75.7 inches by the end of February.

This is the lowest snowfall Bozeman has seen at this point in the year since the 2011-12 winter, and is more than 10 inches lower than any other season since the 2014-15 season. Additionally, the 0.7 inches Bozeman saw in November of this year was the smallest amount in any November since the 1999-2000 season, according to NOAA online weather data.

Eric Sproles, an assistant professor in the Department of Earth Sciences at MSU said, “We're looking at anywhere from around 50 to 65 percent of normal. Which is not great, but it's still the end of February. Typically the peak amount of snow pack is going to accumulate towards the end of March. So March is going to be pretty critical.”

According to Sproles, this year's lower snow levels are due in part to an ongoing El Niño, which refers to high-pressure systems over the Pacific Ocean stemming from warmer sea surface temperatures. In El Niño years, storm fronts from the Pacific Ocean tend to make landfall at lower latitudes. Because Montana gets most of its precipitation from the Pacific Ocean, lower-latitude storms mean less snowfall. 

“This is the fifth strongest El Niño since 1950, which is saying a lot,” Sproles said. “It is anticipated to begin to loosen up or break up a little bit at the end of March. But take that with a grain of salt. We’ll have an exact idea of what happened come the end of June.”

Though there is still plenty of time left for snow to fall, continued low snowfall could lead to lower water levels come spring. 

“The snowpack acts as a natural water tower,” Sproles said. “It accumulates throughout the course of the winter. Stores water way up high where it's very efficient. As it begins to melt it fills streams, it recharges aquifers and groundwater, which we use later both downstream and down calendar.”

This isn't the only low snow year Bozeman has seen in recent years. According to NOAA online weather data, the 1999-2000 season only saw 58.8 total inches. 

“Snowpacks in general are declining. We're anticipating to see warmer winters, which means less snowpack accumulation. Last year was great, this year not so great. We kind of have to be ready for both the highs and the lows,” Sproles said.