Area Forecast Discussion
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
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802 FXUS65 KTFX 301042 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 342 AM MST Sun Nov 30 2025 .KEY MESSAGES... - Freezing fog will result in some icy roads this morning across the Golden Triangle. - Areas of blowing snow will be possible on Monday as westerly winds increase. - Two more rounds of widespread snowfall are expected this week, the first on Tuesday and the second Friday and Saturday. && .DISCUSSION... - Meteorological Overview: An area of high pressure centered over Northeastern Montana this morning will continue to shift to the southeast today. This will allow, after a cold and foggy morning (particularly across the Golden Triangle), warmer air to begin to work its way into the area from the southwest. While areas north and east of a line from Cut Bank to Fort Benton to the Missouri River Breaks will remain trapped in the cold air today, even these areas will see temperatures moderate on Monday. Speaking of Monday, upper level ridging will begin to push into the area on Monday, which will result in some gusty winds across the plains and a few snow showers over the higher terrain of Southwestern Montana as warmer air pushes into the area. However, this ridging will not last long as a shortwave trough will push in from the northwest on Tuesday, bringing some more widespread snowfall to the area followed by another surge of colder air, though not nearly as cold as the air mass currently over the area. The second half of the week will be similar to the first half, with a day or two of quieter weather conditions as a weak upper level ridge builds into the area before a disturbance pushes in from the Northwest on Friday. However, this Friday system does have the chance to be a little more disruptive than the Tuesday system since it might have some more moisture to work with, but there still seems to be some disagreement on just how much moisture this system will bring to the area. Beyond Friday and Saturday, models continue to hint towards a larger scale pattern change, which is likely to result in a period of cooler and unsettled weather next week. - Forecast Confidence & Scenarios: Blowing Snow Monday: As upper level ridging builds into the area on Monday, winds across the plains are very likely to increase, which could result in some blowing and drifting of the snowpack across the area. However, there are a few areas of uncertainty at this point with regards to how big of an issue any blowing or drifting could be, including how much the snowpack compacts and settles today and how quickly (or if) temperatures rise above freezing, which would also put an end to any blowing or drifting snow. However, as it stands the snowpack is not overly deep, so any blowing snow is unlikely to be an issue for more than a few hours before most of the snow is deposited into drifts. Late week snow: While the arrival of some snowfall Friday and Saturday is appearing more and more likely, there remains some uncertainty as to how much snow will fall and how widespread an area the snow will affect. Right now the most likely scenario appears to be a quick hitting snowfall that drops anywhere between 1-4 inches across the lower elevations, but I cant rule out a scenario where northerly winds behind this system bring some more snow to the northerly upslope areas. Ludwig && .AVIATION... 30/06Z TAF Period While VFR conditions are expected to prevail across North Central and Southwestern Montana this evening, there are a few areas of concern overnight tonight. First will be a possible area of fog and/or low stratus across the Golden Triangle (KCTB, KHVR, KGTF) that seems to be in the beginning stages of development. There will also be a few light snow showers south of Interstate 90, but any reductions in vis and/or ceilings here will be short lived. Ludwig && .PRELIMINARY POINT TEMPS/POPS... GTF 24 10 34 27 / 0 0 0 30 CTB 20 8 31 22 / 0 0 0 30 HLN 26 12 35 25 / 0 0 0 30 BZN 24 5 32 21 / 0 0 0 30 WYS 29 2 25 14 / 10 0 10 50 DLN 29 12 36 23 / 0 0 0 20 HVR 6 -6 28 18 / 0 0 0 30 LWT 26 8 35 22 / 0 0 0 20 && .TFX WATCHES/WARNINGS/ADVISORIES... Freezing Fog Advisory until 9 AM MST this morning for Cascade County below 5000ft-Eastern Glacier, Western Toole, and Central Pondera-Eastern Pondera and Eastern Teton-Eastern Toole and Liberty-Hill County-Western and Central Chouteau County. Cold Weather Advisory until 10 AM MST Monday for Hill County- Northern Blaine County. && $$ http://www.weather.gov/greatfalls