Area Forecast Discussion
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
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865 FXUS65 KTFX 052109 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 209 PM MST Fri Dec 5 2025 .KEY MESSAGES... - This afternoon through Saturday there will be light snow across portions of the lower-elevations of North-central, Central, and Southwestern Montana and heavy snow across the mountains. - On Saturday it will briefly cool down across North-central Montana before warming up on Sunday. - Monday through Thursday it will be warm and windy with precipitation chances. && .DISCUSSION... - Meteorological Overview: This afternoon there is northwest flow aloft over North-central, Central, and Southwestern Montana which will keep temperatures cool this afternoon with mountain snow. Early this evening through tonight an Arctic Cold front will move south from Canada. This combined with warm air advection overriding the front will produce a band of snow across North-central Montana along and north of a Cut Bank to Lewistown line. Prior to the snow band forming there is the potential for rainfall before it changes to all snow. There will be a brief burst of heavy snowfall associated with the snow band as it moves to the northeast this evening. On Saturday northwest flow will remain over North-central, Central, and Southwestern Montana. This combined with the cold front that moved through will bring cold temperatures to North-central Montana on Saturday. Snow will linger across the mountains and portions of the lower-elevations of North-central, Central, and Southwestern Montana on Saturday. On Sunday an upper-level ridge will move over North-central, Central, and Southwestern Montana. This will bring warmer temperatures and mostly dry weather to the lower-elevation locations of the area. There will be some light snow in Hill and Blaine Counties Sunday morning. The upper-level ridge will remain over North-central, Central, and Southwestern Montana on Monday which will allow temperatures to warm up some more with dry weather at lower-elevations and mountain snow. Due to an increasing pressure gradient combined with strong mid- and low- level winds, winds will begin to increase Monday afternoon and evening. On Tuesday the upper-level ridge flattens before another upper-level ridge builds in Tuesday afternoon. This will bring precipitation chances and windy conditons to North-central, Central, and Southwestern Montana on Tuesday. On Wednesday the upper-level ridge remains over North-central, Central, and Southwestern Montana this will allow the warm temperatures to continue. Wednesday evening an upper-level shortwave will move through and bring precipitation chances to the area with windy conditions. On Thursday there is an upper-level trough over North- central, Central, and Southwestern Montana. This will bring cooler temperatures, precipitation chances, and windy conditions to the area on Thursday. -IG - Forecast Confidence & Scenarios: Tonight through Saturday morning there is greater than a 60% chance for an inch of snow or greater along and north of a Cut Bank to Lewistown line. From this evening through Saturday night there is greater than a 60% chance for 6 inches of snow or greater along the Rocky Mountain Front. As a result the Winter Storm Watch was upgraded to a Winter Weather Advisory. See the TFX WATCHES/WARNINGS/ADVISORIES section below for details. On Monday there is greater than a 60% chance for wind gusts of 55 mph or greater along the plains west of I-15. On Monday and Tuesday along the Rocky Mountain Front there is greater than a 60% chance for wind gusts of 75 mph or greater. On Tuesday there is greater than a 50% chance for wind gusts of 55 mph or greater across most of North-central, Central, and Southwestern Montana. High wind highlights were not issued at this time but there is a high chance they will be issued in an upcoming shift. On Tuesday and Thursday there is greater than a 50% chance for high temperatures of 45 degrees or greater across most of the lower- elevations of North-central, Central, and Southwestern Montana. On Wednesday there is greater than a 40% chance for high temperatures of 45 degrees or greater across most of the lower-elevations of North-central, Central, and Southwestern Montana. From 5 PM Monday to 5 PM Thursday there is greater than a 50% chance for 6 inches of snow or greater across the mountains of North-central, Central, and Southwestern Montana. IG && .AVIATION... 05/18Z TAF Period A moist and unsettled northwesterly flow aloft will remain over the Northern Rockies for at least the next 24 to 48 hours. MVFR/IFR clouds and mountain obscuration will mostly be confined to areas near mountains through 06/00Z. Then a fast moving shortwave will bring increased snow shower activity and some MVFR/IFR conditions to all areas between 06/00 and 06/09Z. Steadier snow and degraded flight categories will linger into Saturday in the mountains and near the KHVR/KLWT areas. Mountain top winds will exceed 50 kts at times during the passage of the shortwave which will increase mountain wave turbulence and instances of low level wind shear. - RCG && .PRELIMINARY POINT TEMPS/POPS... GTF 16 23 22 41 / 80 50 10 0 CTB 7 16 13 38 / 70 10 10 0 HLN 30 40 28 42 / 90 60 30 10 BZN 28 39 22 40 / 90 70 30 10 WYS 20 32 14 29 / 100 70 50 50 DLN 28 40 23 38 / 70 30 10 0 HVR 9 14 7 31 / 90 50 60 0 LWT 15 26 21 39 / 90 60 40 0 && .TFX WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory from 5 PM this afternoon to 9 PM MST Saturday for East Glacier Park Region-Southern Rocky Mountain Front. Winter Weather Advisory from 7 PM this evening to 11 AM MST Saturday for Bears Paw Mountains and Southern Blaine-Eastern Toole and Liberty-Fergus County below 4500ft-Hill County- Northern Blaine County-Snowy and Judith Mountains-Western and Central Chouteau County. Winter Storm Warning until 2 PM MST Saturday for Big Belt, Bridger and Castle Mountains-Gallatin and Madison County Mountains and Centennial Mountains-Little Belt and Highwood Mountains. Winter Weather Advisory until 11 AM MST Saturday for Elkhorn and Boulder Mountains. Winter Storm Warning until 5 PM MST Saturday for Northwest Beaverhead County. && $$ http://www.weather.gov/greatfalls