MISSOULA — The ridge building over the western U.S. will cause above average temperatures this week.
Highs warm into the 50s today for many around western Montana with light rain showers popping up through the day.
Temperatures continue to warm into the upper 50s and low 60s by Wednesday with light rain showers continuing for northwest Montana.
The warmest temperatures will be along I-90 and south on Thursday and Friday. North of I-90 will also be above average, but less so due to the impacts of an atmospheric river.
Usually when we discuss atmospheric rivers, the main impact is heavy precipitation, but that is not the case this time. While this event does technically meet the criteria of an atmospheric river, due to the high pressure ridge in place rain will remain light. It will also produce consistent cloud cover over northwest Montana, preventing it from warming up as much as other parts of the state.
This is expected to last all week bringing rain chances to northwest Montana through Saturday. The main concern for impacts will be warm temperatures in the mountains combined with frequent precipitation causing dangerous avalanche conditions. For those planning to go into the back country, please monitor the avalanche forecast for the latest conditions.
