Area Forecast Discussion
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
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778 FXUS65 KTFX 100214 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 714 PM MST Sun Nov 9 2025 .KEY MESSAGES... - Mild and breezy to windy conditions are expected for much of the workweek with the warmest temperatures on Monday and Thursday. - Monday`s winds will become strong at times along the Rocky Mountain Front and over the plains west of I15. - A broad Pacific trough moves into the Northern Rockies heading into the weekend, bringing a slight cooldown and a return of mountain snow. && .UPDATE... Minor adjustments were made to the near-term forecast based on updated model guidance. High temperatures on Monday are still on track to be 10 to 15 degrees above normal across the region. High winds are still possible along the Rocky Mountain Front and may cause travel impacts to high-profile vehicles and those towing trailers. One area that might need to be watched for potential strong winds is the eastern side of the Little Belts. HREF probabilities for late Monday into early Tuesday are showing a greater than 80% chance of wind gusts exceeding 55 mph. This is in stark contrast to the NBM which is running at a much cooler 30-40% probability for gusts over 55 mph. For right now there is not enough confidence to warrant any changes to the products but this will be something to watch when the 00Z HREF and 01Z NBM arrive to see what direction the models are trending for this area. In the meantime, folks recreating in the Little Belts and driving along Highway 200 between the Little Belts and Highwoods should be prepared for some strong wind gusts in excess of 45 mph. Precipitation chances across central Montana remain low for tomorrow afternoon. Although one of the models suggests the potential for some light rain, looking at the moisture levels in the atmosphere there is not much support for any of that precipitation reaching the ground. Otherwise the going forecast remains on track. -thor && .DISCUSSION... /Issued 433 PM MST Sun Nov 9 2025/ - Meteorological Overview: Stubborn low clouds and patchy fog along the Milk River Valley has been the primary concern for much of today. The fog has since dissipated and any redevelopment tonight will be temporary with increasing high level cloudiness and southwesterly breezes moving into most of this area around or shortly after midnight. Ridging aloft will flatten with strong westerly flow developing late tonight into Monday on the order of 50 to 80 kts between 500 and 700 mb. Mountain wave activity and a tightening surface pressure gradient will compliment the increased westerly flow aloft and bring periods with winds gusting in the 60 to 75 mph range along the Rocky Mountain Front and the plains west of I15. Winds will be gusty east of I15 as well, but warm air advection and extensive high clouds should preclude widespread instances of 55 mph + surface wind gusts. If any gusts do occur in these areas it will be in the evening hours when a shortwave with weak northwest to southeast oriented cold air advection passes though the region. Breezy and mild conditions are expected for much of the remaining workweek with afternoon temperatures running as high as 15 to 20 degrees above average, warmest on Thursday. A broad split trough then approaches the Northern Rockies late Thursday through Saturday. Winds shouldn`t be as strong with this trough being more meridional oriented, but southerly flow aloft may bring windy conditions to the southwest late Thursday into Friday. There`s an expectation for increased precipitation and mountain snow Friday and Saturday despite at least a portion of this system`s energy looking to dive southward into the Great Basin. Ensemble members diverge for the second half of the weekend into early next week, with timing discrepancies between troughs and ridges. - RCG - Forecast Confidence & Scenarios: Periods of strong winds along the Rocky Mountain Front and plains west of I15 on Monday... There`s a general expectation for windy conditions over much of North-central Montana on Monday given the elevated westerly flow aloft mentioned above. With warm air advection and cloud cover inhibiting widespread surface transfer of the stronger upper level flow, there will be a higher dependence on mountain wave activity to bring stronger winds to the surface. This will confine the strongest winds to areas along the Rocky Mountain Front and the plains along and west of I15, with that boundary even shifting farther west to highway 89 for plains locations south of Pendroy. There looks to be a period of strong winds late tonight into Monday morning and then again in the afternoon. Most of these areas have a 60 to 90% chance for gusts exceeding 55 mph with a 50 to 80% chance for gusts exceeding 75 mph over the immediate eastern slopes of the Rocky Mountain Front. Winds will mostly stay in the 30 to 50 mph range for other locations, but a few isolated gusts over 55 mph may occur during the passage of a weak cold front late Monday afternoon and evening. All the high wind watches were upgraded to warnings which now run from 2 am to 9 pm. I also considered adding the Sweetgrass hills as well with the stripe of H850 winds moving though on Monday , but held off for now because if the aforementioned confounding factors. This situation will be monitored by incoming shifts. - RCG && .AVIATION... 10/00Z TAF Period The main concern this TAF period will be for increasing surface winds, primarily over the plains. A few instances of low-level wind shear will be around through the early overnight on the plains as surface winds remain weaker for a few hours while winds aloft increase. Confidence was highest in this occurring at KCTB over an extended period, with confidence too low in an extended duration of LLWS elsewhere to include in TAFs at this time. Gusty surface winds become more common through the morning and early afternoon Monday, mostly over the plains. -AM The KWYS TAF will not be issued until airport operations resume next spring. && .PRELIMINARY POINT TEMPS/POPS... GTF 44 65 43 58 / 0 10 0 0 CTB 40 62 37 52 / 0 10 0 0 HLN 34 61 41 57 / 0 0 0 0 BZN 30 61 34 59 / 0 0 0 0 WYS 18 48 24 47 / 0 0 0 0 DLN 32 60 33 56 / 0 0 0 0 HVR 28 64 34 57 / 0 10 0 0 LWT 35 64 38 56 / 0 0 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... High Wind Warning from 2 AM to 9 PM MST Monday for East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera- Northern High Plains-Southern High Plains-Southern Rocky Mountain Front. && $$ http://www.weather.gov/greatfalls