The National Weather Service has issued a WINTER STORM WATCH for most of SW Montana Tuesday evening into Thursday morning.
Rain will change to all snow Tuesday evening. Snow accumulations of 2"-8" are likely for all valleys and up to or over a foot of snow for most mountains and passes. Gusty winds are likely with this storm. Significant impacts to travel will develop by Wednesday morning, especially between Bozeman and Billings. Heavy wet snow loading on trees with leaves could lead to power outages.
Winter Storm Watches are issued well ahead of an approaching winter like storm. As the storm gets closer the watch will likely be upgraded to a winter storm warning or a winter weather advisory.
BOZEMAN – Another blast of winter like weather will impact Montana beginning Tuesday. Forecast models have been consistent with their solution that a strong Canadian cold front will drop through Montana Tuesday morning through Wednesday afternoon.
This is a complex weather pattern change as a High-pressure ridge is currently producing slightly warmer temperatures Sunday into Monday and 60s are likely Monday into Tuesday. This will help produce mostly rain by Tuesday afternoon as the next weather maker moves into our region. However, behind this Canadian cold front temperatures will fall well below freezing into Wednesday morning and rain will change to snow at all levels including the valley floor.
Narrowing down how much snow will hit SW Montana is extremely difficult with this type of temperature swings. Some forecast models show very little snow accumulations and others have 6”-10” for valleys.
Right now (this will change) the most likely outcome will be 2” – 5” of valley snow and higher mountain passes could see a foot or more.
Traveling across Montana Tuesday night through Thursday morning will be tricky with wet roads, gusty winds, much colder temperatures producing icing on roadways, and reduced visibility with falling snow. Plan accordingly to adjust to changing road conditions and please allow for slow-go travel and add a good 20 minutes to half and hour for commutes Wednesday into Thursday if traveling over mountain passes.
The above weather briefing is an early look at what could develop this week. As new weather model runs come in tonight and Monday we will have a better handle on timing, intensity, and impacts on the next weather maker.