BILLINGS — Moisture will build across the area on Thursday through southeasterly low-level winds. This, combined with an approaching storm system moving east from Northern California, will bring chances of scattered afternoon showers and thunderstorms, primarily across southern areas. A few storms in southeastern Montana could turn stronger, producing gusty winds and heavy rain, while chances remain lower in south-central Montana.
Atmospheric moisture will surge over 200% of normal across the region Friday afternoon through Saturday, opening the door for heavy rainfall across the entire area. The low-pressure system is forecast to be a slow mover, which would mean long-lasting, widespread rain over the weekend. There is a MARGINAL risk for excessive rainfall over the entire area Friday and Saturday. In fact, models currently give most of our region a 40–80% chance of widespread accumulation exceeding one inch, especially in south-central Montana and the Bighorns. Saturday looks to be especially wet. If you have weekend outdoor plans, prepare for steady rain and the possibility of flooding in susceptible areas like burn scars and low-lying locations.
Between Friday afternoon and evening, conditions are now leaning more favorable (but still on the lower end) for a few strong to severe thunderstorms, most likely east of Billings and moving eastward at the moment. The main threats with any severe storms that do pop up will be strong wind gusts, large hail, and heavy rainfall. If you have outdoor plans Friday afternoon or evening, keep a close watch on the forecast.
Rain will begin to clear out late Sunday into Monday, though models disagree slightly on the timing. Some clear most of the region by early Sunday afternoon, while others keep rain lingering into Monday morning. The current consensus dries out the western foothills Sunday afternoon, but keeps a chance of showers going across central areas through Sunday night. All precipitation should finally wrap up in far eastern Montana by Monday afternoon.
The forecast does include some snow, but accumulations are expected only in the highest mountain peaks of the Beartooths, Absarokas, and Crazies, where generally less than 5 inches of snow could fall through the weekend. While we are keeping an eye on pass conditions along the Beartooth Highway, significant travel impacts are not expected and winter weather advisories are unlikely at this time.
Daytime highs will warm into the upper 70s to low 80s Thursday and Friday, then cool to the mid-60s to low 70s on Saturday and Sunday, with Sunday being the warmer of the two days. The warmer temperatures will continue into early next week with highs generally in the mid to upper 70s, with some locations possibly reaching into the low 80s.
Miller Robson
Q2 Morning Meteorologist
miller.robson@ktvq.com
