FXUS65 KTFX 051221 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 521 AM MST Tue Mar 5 2024 .Aviation Section Updated... .SYNOPSIS... Snowfall returns to Southwestern Montana today as a fast moving weather system moves across the Snake River Valley. Further north, expect temperatures to moderate a bit with most areas seeing temperatures in the mid 20s to mid 30s. Beyond tomorrow, expect temperatures to warm up across the area through the end of the week. && .DISCUSSION... A low pressure system will move through southern Montana today bringing snow to area now through tomorrow morning. Snow totals in southwestern Montana, compared to the last forecast, decreased slightly with accumulations still more than enough to justify an advisory but not enough to upgrade to a warning. That being said, there is still a concern for both snow bands developing and blowing snow this afternoon as winds will be gusting up to 40 mph at times. Should these two come together with a greater force than what is currently forecasted, the advisory will need to be upgraded. Snow showers will taper off overnight and end by late Wednesday morning. Behind this system, temperatures will warm up as a ridge starts to build over the western CONUS with weekend temperatures in the 40s and 50s across lower elevations. Heading into early next week, long range models continue to point towards the ridge breaking down which will bring unsettled weather back to the region. However the specifics remain uncertain at this time. -thor && .AVIATION... 515 AM MST Tue Mar 5 2024 (05/12Z TAF Period) North Central Montana (KCTB KHVR): Low- to mid-level clouds will persist through the day with a slight chance of snow showers across the hi-line after 06/00Z. KCTB and KHVR are unlikely to be impacted by snow showers, however, there is a chance for patchy fog development near KHVR after 12Z. Central Montana (KGTF KLWT KHLN): VFR conditions are forecast to continue with passing high- and mid-level cloudiness. However, a disturbance will move east through the area between 12Z and 00Z, which could bring some mountain top obscuring snow showers. Otherwise, surface winds should remain light. Southwest Montana (KBZN KEKS): VFR conditions will continue until around 15Z, then a disturbance will lower conditions to mostly low VFR/MVFR in snow showers with mountain obscuration; periods of IFR conditions are also possible, especially after 21Z. Southerly surface winds will also increase south of Interstate 90 between 14Z and 20Z, producing gusts in the 25 to 40 kt range on ridge tops and through south-north oriented valleys, and causing low level wind shear with westerly winds aloft causing mountain wave turbulence. -Coulston/thor Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .PRELIMINARY POINT TEMPS/POPS... GTF 36 12 37 14 / 0 0 0 0 CTB 29 3 31 7 / 0 10 0 0 HLN 33 13 35 12 / 20 0 0 0 BZN 29 11 33 9 / 50 50 0 0 WYS 27 7 29 7 / 90 80 30 10 DLN 30 11 32 10 / 40 40 0 0 HVR 21 4 23 4 / 0 10 10 0 LWT 32 11 32 11 / 20 10 10 0 && .TFX WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 5 AM MST Wednesday for Gallatin and Madison County Mountains and Centennial Mountains. Winter Weather Advisory until 5 AM MST Wednesday for Madison River Valley-Ruby Mountains and Southern Beaverhead Mountains. && $$ http://www.weather.gov/greatfalls