BOZEMAN – Friday afternoon thunderstorm activity is sparse around SW Montana but there are a few isolated mountain rumbles developing in our region. Most of these appear to be weak and short-lived and will quickly diminish around sunset.
The bigger weather issue Friday is a broad area of heavy rain with embedded thunderstorms sitting over SE Montana. From Billings to Miles City southward moderate to heavy rainfall could lead to ponding and possible lowland flooding through this evening.
The National Weather Service has issued a FLOOD WATCH for SE counties of Montana through midnight Friday.
THE NEXT WEATHER MAKER:
The next round of showers and thunderstorms will roll up into SW Montana Sunday afternoon through Tuesday morning.
Strong thunderstorms are possible Sunday afternoon and evening and a few severe thunderstorms are possible over SW Montana but a better chance for severe thunderstorms is likely for Northcentral counties of Montana. Look for heavy rain, small to large hail, strong outflow wind gusts, and frequent and deadly lightning Sunday afternoon and evening.
This is an early look at potential rainfall totals by Monday morning. Keep in mind this will likely change in the next day or two but this is what forecast models are suggesting. Greatest impacts could be (will change) from Dillon to White Sulphur Springs with moderate rainfall along that line and to the north.
City by City Forecast:
BOZEMAN: LOW: 48°; HIGH SATURDAY: 80°. A few late afternoon thunderstorms are possible but will quickly end after sunset. Saturday look for similar conditions but the next weather maker will arrive by Sunday afternoon with a much better chance for showers and thunderstorms.
BUTTE: LOW: 47°; HIGH SATURDAY: 77°. Isolated rumbles will diminish by early evening around Butte. Look for mostly dry weather Saturday with a slight chance for a pop-up thunderstorm. Sunday will become more active with showers and thunderstorms, some strong, by Sunday afternoon.
DILLON: LOW: 48°; HIGH SATURDAY: 80°. Isolated mountain rumbles near Dillon will be ending by sunset tonight. Saturday a few mostly mountain storms are possible. Sunday the next weather maker arrives with increasing showers and thunderstorms, some could be very strong, by Sunday afternoon.
WEST YELLOWSTONE: LOW: 37°; HIGH SATURDAY: 76°. The overall weather pattern for West Yellowstone is dry and cool for Saturday. A cold front will arrive late on Sunday and will bring an increasing chance for showers and thunderstorms Sunday evening.