Play Live Radio
Next Up:
0:00
0:00
0:00 0:00
Available On Air Stations

Rivers Expected To Rise As Heat Wave Moves Through Montana

National Weather Service Missoula

It’s not your imagination: It’s been an unusually cool Montana May. That’s about to change in a big way.

A high-pressure system building over western Montana will lead to temperatures warming to near 90 degrees by Friday. That’s 15-20 degrees above normal for this time of the year according to National Weather Service-Missoula meteorologist Jeff Kitsmiller.

"We still have at least 100% snowpack in most of the mountains. The Clark Fork Basin is right at 100%, so we’ll melt off more of that snow and put that in the rivers. So all the rivers will come up, the Clark Fork will stay above flood stage and it’ll rise. It won’t get as high as the last rise. And everything else, like the Bitterroot River looks like it's going to rise but it should stay below any type of a flood stage right now.”

Saturday could top out at 94 degrees before the system moves east to heat up eastern Montana.

Kitsmiller said the heat wave may come as a shock given May’s below normal temperatures. He advises caution to anyone turning to our swollen and cold rivers and streams to beat the heat.

"It is really cold. I was taking a look around at stream temperatures, and they're all, even lake temperatures. they were all in the 40s, for the most part. Some are in the low 40s, some are a little bit warmer. That means it’ll probably only take about an hour of being in that water before you actually get to hypothermia.”

Forecast models are calling for the potential of strong to severe thunderstorms Saturday, before temperatures moderate back into the 70s next week with increasing chances for showers and thunderstorms.

Copyright 2020 Montana Public Radio. To see more, visit Montana Public Radio.

Edward O'Brien is Montana Public Radio's Associate News Director.