A WIND CHILL WARNING has been issued for most of Montana.
A WINTER STORM WARNING is in effect for parts of western and central Montana.
A WINTER WEATHER ADVISORY has been issued for central and northcentral Montana.
A WIND CHILL ADVISORY has been issued for southcentral and southeast Montana.
Incredibly, dangerously, deadly cold. Over the next few days a record breaking cold arctic airmass will spill into Montana and eventually most of the United States. These temperatures will be so cold, this will be the coldest some people ever see in their lifetime. Actual air temperatures will drop to between -30 and -40 for most of Montana, with some of the coldest locations possibly dropping to -50 to -60. Wind chill values will range from -40 to -65 for most of the state through Wednesday into Thursday morning. And before that cold arrives, a signficant snowstorm will produce several inches of snow to nearly a foot. Low pressure will move toward Montana from the Pacific. This moisture-laden airmass will run into an arctic aimass resulting in light, powdery snow. Snow will increase across the state through Tuesday. Highs will range from -10 up on the Hi-Line to near 32 around Missoula. Snow will continue to fall Tuesday night into Wednesday morning. As an arctic front moves through Wednesday morning, the snow will come to an end but the wind will be the strongest, gusting to 20-30mph. The wind will not stay that strong for long, easing up by the afternoon. However, high temperatures will range from -10 to -20 on Wednesday so any wind will significantly lower the wind chill value. Cloud cover will break up through the afternoon and evening as arctic high pressure moves in. Temperatures across the state will bottom out between -30 and -40, with some of the coldest locations down to -50 to even -60. Records will be broken. Thursday will be sunny but very cold with highs in the -10 to -20 range, wind chill values could still exceed -40 to -50, especially over eastern Montana. Thursday night's lows will generally be between 0 and -20 which is cold, but not as cold. Friday, get ready for the start of some major changes. A Pacific airmass will be moving in with much warmer temperatures. It may take some time but gradually the arctic airmass will retreat and most of the state will warm up. Friday will be cloudy with some areas of light snow. Western Montana will warm into the 10s and 20s, with eastern Montana holding onto the arctic air the longest and highs staying below 0. Saturday will be mostly cloudy with a warmer wind pushing the arctic air out of the state. Highs will warm into the 20s and 30s, and a few spots may even hit 40. That's 40 above zero. Christmas Day on Sunday will be mild and mostly cloudy. Highs will be in the 30s and 40s with a few mixed rain and snow showers in the lower elevations and a few snow showers in the mountains. Strong wind gusts over the plains could exceed 40mph. Mild, Pacific air will continue across the state for most of next week. Some areas on Monday could even hit 50 degrees. So parts of Montana could have a temperature swing of 80-100 degrees from Wednesday night to Monday. Please be very careful with this life threatening cold.
Stay safe,
Curtis Grevenitz
Chief Meteorologist