A major winter storm producing historic snowfall amounts on the Rocky Mountain Front will continue to pound the state. A WINTER STORM WARNING remains in effect for the Rocky Mountain Front through Marias Pass into the mountains of northwest Montana into Monday. A WINTER WEATHER ADVISORY has been issued for the Hi-line down through Great Falls to Helena until Monday evening. FEET of snow, up to 40″ has fallen already on the Rocky Mountain Front. Another 20-30″ of snow is possible, putting storm totals upward of 60-70″. Incredible. A sharp front continues to dangle through the central part of the state, separating arctic air from warmer Pacific air. South of the front, temperatures are in the 30s, 40s, and even near 50. North of the front, where the snow is flying, temperatures are in the 0s and 10s. This front will work its way south through Montana on Monday, with colder air returning to all locations. Snow will accompany the front, with several inches falling in the lower elevations. Snow could be heavy for a brief time as the front passes, which will likely be in the afternoon and evening. After some places reached the 40s to near 50, many surfaces will refreeze, leading to dangerously slippery conditions. Monday night’s temperatures will fall below zero. Tuesday, a few snow showers will move through the state, but the significant snow will be over. Highs will be very cold, in the -0s to around 15. Wednesday, another surge of warmer Pacific air will push toward the state. The mixing of this airmass with the arctic air in place will result in widespread light snow. A coating up to a few inches will accumulate. Temperatures will slowly warm all day long, from the 0s to the 20s to near 30 by late in the evening. Temperatures will continue to warm through the night, and Thursday will be a much warmer day across the state. Highs will reach the 40s and 50s, with a west wind up to 40mph. A few rain showers will fall, and snow levels will be way high up in the mountains. Warm air in the 40s and 50s will continue Friday, but a sharp cold front will produce showers of rain and snow. Colder temperatures back below freezing will move in by night. Next weekend will be cooler with snow showers on Saturday, but Sunday will be a mostly sunny day. Another warmup will hit the state through the middle of February.
Please be careful driving the next few days, and avoid travelling along the Rocky Mountain Front and through Marias Pass if you can.