331 FXUS65 KTFX 271743 CCA AFDTFX Area Forecast Discussion...Corrected Aviation Section National Weather Service Great Falls MT 1143 AM MDT Wed Oct 27 2021 ...Aviation Section Updated... .SYNOPSIS... A weather system passing through today will bring strong winds over North-central Montana. A brief ridge will move in Thursday, leading to the warmest temperatures of the period. A cold front then enters the area Friday evening, bringing a chance for snow over the plains. && .Morning Update... Forecast is on track and no updates were made outside of re- running hourly wind trends to best incorporate a brief wind reduction this morning, before winds ramp back up with increased mixing this afternoon. Otherwise the forecast is handling the situation well, with a period of High Winds still expected to impact the plains of Central and North Central Montana through the afternoon hours today. While a few valley locations in Southwest Montana may reach High Wind criteria, expect these reports to be far and few between to warrant an extension of the current High Wind highlights further south. - Moldan && .AVIATION... 1143 AM MDT Wed Oct 27 2021 (27/18Z TAF period) VFR conditions prevail for much of the North-Central and Southwest region; however, periods of MVFR conditions expected briefly at KWYS as showers pass through this evening, and then return back to VFR through the remainder of this TAF. Gusty westerly winds continue throughout the region, though lighter winds are possible occasionally, with the main threat of gusty winds to subside by tomorrow. Potential for mountain waves exist along the Rocky Mountain Front during this period, although confidence is low at this time. Mountain obscurity, especially along the Rocky Mountain Front and far Southwest region, is possible due to low ceilings. -Pierce Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PREV DISCUSSION... /ISSUED 546 AM MDT Wed Oct 27 2021/ Today and Thursday... An upper level disturbance passing through the region will produce gusty winds along the Rocky Mountain Front and into the plains today. The strongest winds will begin along the Rocky Mountain Front before sunrise. Over the plains, the strongest winds will commence shortly after sunrise, once thermal mixing begins. The high wind warning in effect is being maintained as-is at this time, which expires at 6 PM MDT. An upper level ridge will move in starting Thursday, leading to warmer temperatures and largely dry weather for most. A considerable pressure gradient will set up along the Rocky Mountain Front, however. This gradient, paired with upper level energy, will allow for a gusty west to southwest wind Thursday afternoon into early Friday morning focused along the Rocky Mountain Front. Given the strongest gusts will be focused along the Rocky Mountain Front, no wind highlights are anticipated at this time. Friday through Sunday... The upper level ridge responsible for the brief warm up will quickly exit Friday. An approaching upper trough will propel a cold front through the area late Friday. Temperatures behind the front will support a transition to snow Friday night into Saturday morning across the plains. At this point, snow accumulation on the plains is generally expected to be in the 1-3 inch range. Worth noting is that there is not great agreement yet regarding the timing or strength of the front. A quicker or stronger front may result in greater impacts on the Friday night commute across the plains. I elected to lean closer to GFS guidance during this frontal passage, which is a bit cooler and more progressive than NBM. The remainder of the weekend looks cooler than average, with a barely mentionable chance for precipitation in Southwest Montana. Monday through Wednesday... Cluster analysis supports a return to upper level ridging over the west early next week. The magnitude of the ridge is a bit more uncertain at this time, which limits confidence in a significant warm up. Nonetheless, high temperatures will be on the cool side to start the week, but return closer to normal towards Wednesday. -AM && .PRELIMINARY POINT TEMPS/POPS... GTF 51 35 60 48 / 80 10 20 10 CTB 49 32 56 43 / 20 10 20 40 HLN 51 35 60 40 / 60 10 10 10 BZN 50 30 57 35 / 20 10 10 0 WYS 40 22 42 28 / 40 10 10 10 DLN 48 31 55 35 / 20 10 10 0 HVR 57 30 58 43 / 20 0 10 30 LWT 50 30 56 44 / 50 0 20 10 && .TFX WATCHES/WARNINGS/ADVISORIES... High Wind Warning until 6 PM MDT this evening Cascade...Central and Southern Lewis and Clark...Chouteau...Eastern Glacier... Eastern Pondera...Eastern Teton...Judith Basin...Liberty... Meagher...Northern Rocky Mountain Front...Southern Rocky Mountain Front...Toole. && $$ http://www.weather.gov/greatfalls