Area Forecast Discussion
Issued by NWS Great Falls, MT
Issued by NWS Great Falls, MT
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913 FXUS65 KTFX 261738 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 1145 AM MDT Thu Sep 26 2024 .SYNOPSIS... Breezy to windy conditions and seasonably mild temperatures are expected for the next day or so before brief warming takes place for the first half of the weekend ahead of the next weather system. The aforementioned system will bring another brief cool down, slight chances for showers, and more breezy to wind conditions for Sunday and Monday. && .UPDATE... For the update this morning, only minor adjustments were made to the winds and temperatures based on the latest model guidance. Otherwise, everything else remains on track and no major changes were made to the going forecast. -thor && .AVIATION... 26/18Z TAF Period Expect VFR conditions to continue over the next 24 hours, though a cold front pushing through the area will bring a few isolated rain showers and gusty winds across North Central and Southwestern Montana, with the strongest winds and best chances for a shower across the plains. Otherwise, areas of mountain wave turbulence will be possible, as will speed shear on approach to valley terminals. Ludwig Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PREV DISCUSSION... /ISSUED 520 AM MDT Thu Sep 26 2024/ An initial wave of stronger winds, with gusts in the 40 to 55 mph range, moved through the Northern Rocky Mountain front and nearby high plains earlier tonight. Wind speeds have leveled off since then, but a stripe of 40 to 50 kt H700 winds arrives for another opportunity for strong surface wind between now and 29/16Z. Then winds aloft relax and diurnal mixing takes over and maintains windy conditions in the aforementioned areas through this afternoon. Given the anticipation of a second wave of winds, I will leave the High Wind Warning as is for now. Other plains locations will see elevated westerly winds as well, but wind gusts will mostly remain in the 25 to 45 mph range. Temperatures in the wake of the front will cool closer to the seasonal average for this time of year. Similar conditions are expected on Friday as westerly flow aloft remains elevated, but the lack of cold air advection and shortwave energy will result in overall lighter wind speeds and warmer temperatures than today. Ensembles generally favor a continued progressive west to southwesterly flow aloft this weekend into early next week, though there are still differences among members in regards to the timing of passing shortwave disturbances. Overall, this looks to result in temperatures oscillating from near average to above average and back again, along with periods of breezy to windy conditions. I maintained the NBM solution which features frontal passages and associated cool downs/windier periods and slight chances for showers Sunday into Monday and again Tuesday into Wednesday. - RCG && .PRELIMINARY POINT TEMPS/POPS... GTF 72 49 81 46 / 0 0 0 0 CTB 65 45 73 41 / 10 0 0 0 HLN 76 47 82 49 / 0 0 0 0 BZN 78 43 81 44 / 0 0 0 0 WYS 71 33 73 33 / 0 0 0 0 DLN 75 42 79 44 / 0 0 0 0 HVR 71 45 81 46 / 10 0 0 0 LWT 70 45 79 47 / 0 0 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... High Wind Warning until 3 PM MDT this afternoon for East Glacier Park Region-Eastern Glacier, Western Toole, and Central Pondera- Eastern Toole and Liberty-Northern High Plains-Southern High Plains-Southern Rocky Mountain Front. && $$ http://www.weather.gov/greatfalls