BOZEMAN – Montana State University assistant professor Eric Sproles, an expert on snow and water science, told a national audience Tuesday that this year’s warm, dry weather in the western United States is exactly what scientists would expect to see given current conditions in the Pacific Ocean.

Sproles, in a live interview with CBS anchor Errol Barnett, said the weather is warmer and drier than usual because of the periodic phenomenon known as El Niño, which causes warm waters in the Pacific to push the jet stream south of its usual position. El Niño results in mild winters in the northern U.S. and wetter conditions in the Gulf Coast and southeast regions of the country.

Sproles said during the network’s “Climate Watch” segment that when precipitation does occur in an El Niño year, it’s often in the form of rain rather than snow, resulting in below average snowpacks.

In the western U.S., Sproles said, “snow is our savings account” that slowly recharges groundwater and streams as it melts in the warmer months. A dry winter may impact agriculture and hydropower generation later in the year, he said.

Asked whether the West should brace for a difficult wildfire season ahead, Sproles said a lack of snow may enhance fire conditions but that it’s too soon to make fire predictions.

He said recognizing that a drought is occurring can help western communities evaluate whether they will need to “tighten the belt a little bit” in terms of water usage in the months ahead.

Sproles is an assistant professor in MSU’s Department of Earth Sciences in the College of Letters and Scienceand director of the Geospatial Snow, Water and Ice Resources Lab and Geospatial Core Facility.