Area Forecast Discussion
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
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426 FXUS65 KTFX 262128 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 228 PM MST Wed Nov 26 2025 .KEY MESSAGES... - Areas of dense fog may redevelop tonight along the Hi-line. - Snow develops across north-central Montana late Thursday and intensifies overnight with snow developing across southwest Montana Friday. - Gusty north winds and falling temperatures follow the passage of a cold front Thursday night through Friday with areas of blowing and drifting snow. - Coldest air of the season so far will arrive this weekend. && .DISCUSSION... - Meteorological Overview: A northwest flow aloft with embedded moisture will supply mainly mid to high level clouds across the area through tonight, though a few light mountain snow showers cannot be ruled out. Surface high pressure centered north and northeast of the area will expand southward overnight with fog likely to redevelop for the same Hi- line areas that saw fog this morning with some potential for areas of fog to expand further southwest across north-central MT later tonight into Thursday morning. Warm advection ahead of an incoming Pacific shortwave will generate some light snow or flurries as it lifts through the area Thursday with steadier snow developing across northwest portions of north- central MT as front stalls late Thursday afternoon and evening. Snow intensifies along the west-east frontal zone Thursday night, which models have trended further north with today, now expected to be focused near the Hi-line. Additional shortwave energy arriving from the west and dropping south from Canada will sweep southeast through the Northern Rockies and MT late Thursday night through Friday, bringing a more widespread snowfall with areas of upslope- enhanced snow lingering into Friday evening across eastern portions of central and southwest MT before ending. Surface high pressure and a colder airmass surges south from AB Thursday night with gusty north winds developing overnight and spreading through southwest MT on Friday. The combination of falling snow and gusty north winds will add to potential travel hazards on Friday. Temperatures fall to the teens and twenties following the frontal passage, which occurs early Friday morning across north- central and central MT but may not be until Friday afternoon across southern portions of southwest MT. The cold airmass settles across the region this weekend with mainly dry conditions expected through Monday. Overnight low temperatures in the single digits above/below zero are expected Saturday morning and again Sunday morning with afternoon temperatures in the teens and low twenties. Temperatures look to moderate some next week but an unsettled northwest flow persists with additional opportunities for snow by the middle of next week. Hoenisch - Forecast Confidence & Scenarios: There has been a northward trend in the axis of heaviest snowfall amounts for the late Thursday through Friday period with areas along the Hi-line to the AB border most favored to receive amounts in excess of 6 inches from both the initial warm front Thursday night and and enhanced snow as the upper level wave tracks east Friday morning. A 40-60% probability for amounts in excess of 4 inches still exists for areas as far south as the US-87 corridor across central MT and much of the central MT mountain ranges as far south as the Bridger range and Bozeman pass, where snow is likely to peak Friday morning across central MT and Friday afternoon across southwest MT. The combination of falling snow and winds could impact visibility for many areas on Friday with potential for particularly hazardous conditions across portions of Glacier, Toole and Pondera counties, where both several inches of snowfall are expected along with wind gusts in excess of 30 mph at times Friday morning. North winds with gusts in excessive 30 mph are also likely Friday through Judith Gap and the Broadwater county south through Three Forks and Twin Bridges areas, where snowfall amounts will be lighter but still be enough to produce at least minor impacts. Another factor to consider for SW MT is the potential for a flash freeze of moisture on road surfaces later Friday with the later arrival of falling temperatures. Hoenisch && .AVIATION... 26/18Z TAF Period VFR conditions will prevail across all but the KLWT and KHVR terminals. During the first 6 hours of this TAF Period there will be intermittent IFR-level ceilings at the KHVR terminal. Then fog will move in to the terminal with LIFR-level ceilings. Then LIFR- level fog will affect the terminal after 27/05Z through the end of the TAF Period. At the KBZN, KHLN, and KGTF terminals there is a 20 - 40% chance for snow after 27/12Z through the end of the TAF Period. There will be mountain obscuration across North-central, Central, and Southwestern Montana during the majority of this TAF Period. -IG && .PRELIMINARY POINT TEMPS/POPS... GTF 24 36 18 24 / 0 30 80 100 CTB 14 30 11 18 / 0 50 100 90 HLN 26 43 20 28 / 10 30 50 100 BZN 22 44 24 33 / 10 20 20 90 WYS 15 38 18 35 / 10 40 10 70 DLN 26 46 25 42 / 10 10 0 50 HVR 7 27 14 25 / 0 20 90 100 LWT 21 39 17 27 / 10 20 70 100 && .TFX WATCHES/WARNINGS/ADVISORIES... Winter Storm Watch from Thursday afternoon through Friday afternoon for Bears Paw Mountains and Southern Blaine-Cascade County below 5000ft-East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera-Eastern Pondera and Eastern Teton-Eastern Toole and Liberty-Hill County-Northern Blaine County-Northern High Plains-Southern High Plains-Southern Rocky Mountain Front-Western and Central Chouteau County. Winter Storm Watch from late Thursday night through Friday afternoon for Upper Blackfoot and MacDonald Pass. && $$ http://www.weather.gov/greatfalls