More sun on Sunday, soggy early week with flood concerns
Showery weather on Saturday will begin to dissipate overnight, leading to a partly cloudy and cool Sunday morning with lows in the mid to upper 30s. Sunday will be a little warmer with less rain. Only a few isolated showers are expected in the afternoon in southwest Montana. Highs will graze the 70s briefly in the afternoon west of the divide with areas further south remaining in the 60s. A thunderstorm or two is possible Sunday night into Monday morning.
A strong low pressure system will arrive late Monday after lurking to the south on Sunday. Showers and thunderstorms will develop and move north-northwest in the afternoon. These storms don't have the profile to become severe, but some could bring a lot of lightning. The heart of the storm moves over Montana on Tuesday.
Since Friday the projected storm track has shifted a little to the west. This puts the heaviest rain in our area around Butte and Missoula with 1 to 2 inches in a 48 hour period. A FLOOD WATCH will be in effect for Butte, Anaconda, Deer Lodge, Philipsburg, Drummond, and the surrounding countryside Tuesday. Creeks will swell to bursting and sections of the Clark Fork will approach flood stage. Bozeman will see some heavy rain but it appears to be around an inch with less potential for higher amounts. Kalispell sees much less rain than areas further south. Snow will fall in the mountains above 7000 feet. Temperatures in the valleys will only reach the mid 50s to around 60 degrees.
River levels will jump 1 to 2 feet by next Thursday as they try to send all the fresh rain downstream. Minor flood stage or action stage is possible on many rivers in the region due to the rain.
The forecast beyond Wednesday, which will be mostly sunny, remains in a bit of limbo as the computers are having a tough time pinning down the rain potential. Missoula and Kalispell will likely see another day of rain late next week while southwest Montana stays dry. Expect temperatures to rebound toward normal with highs in the 70s.