BUTTE – We seem to be stuck in a cycle of convective activity in the late afternoon to early evening hours through early next week. Why?
High pressure is parked over the central Rockies and a deep trough continues to set off the Pacific NW coast. This is producing a SW flow aloft for Montana which is kicking temperatures up into the 80s and 90s but it’s also paving the way for moisture to stream into the state.
Thunderstorm activity will reach its peak during the late afternoon hours which coincides with the warmest temperatures of the day with the greatest lift.
Storm Prediction Center will keep a low or “Marginal” risk for damaging thunderstorms over SW Montana all weekend with the greatest potential for severe thunderstorms over Jefferson, Broadwater, Northern Gallatin, and Northern Park counties Sunday afternoon.
Watch for building storm clouds to develop over most mountain ranges by early afternoon and as they begin to migrate to the ENE storms will increase in strength. Watch for brief heavy rain, strong outflow wind gusts, small to large hail, and frequent and deadly lightning.