BOZEMAN – The blocking High-pressure ridge that has been producing extreme heat and dry weather is finally breaking down at least for a few days allowing Pacific storms to pass through the state.
An upper-level Low Friday afternoon is spinning into Eastern Idaho and SW Montana. This will bring some scattered showers and isolated thunderstorms to SW Montana Friday afternoon but most of the active weather will end around sunset Friday.
Some rotating bands of showers and thunderstorms have the potential to produce some moderate to heavy rainfall but those should be isolated events and not widespread.
Saturday we will be between systems and the overall weather pattern is looking great with mostly dry conditions, near normal temperatures and increasing surface winds late into the day.
The next weather maker will be a mature Pacific storm with a surface cold front and area of Low-pressure. This storm will begin to dig into NW Montana Sunday morning and the cold front will pass through SW Montana by Sunday afternoon.
This frontal system will bring increasing surface winds, scattered showers and a few thunderstorms. The Storm Prediction Center has a low risk or “moderate” risk for a few strong to severe thunderstorms Sunday afternoon along and east of the divide for SW Montana. This means a few storms could produce damaging wind or damaging hail.
Once this system spins out of the region a cooler NW flow will continue into the first half of next week. Forecast temperatures will be slightly cooler than normal Sunday through Wednesday. By the end of next week look for temperatures to rise again as High pressure redevelops across the state.