FXUS65 KTFX 191003 AFDTFX Area Forecast Discussion National Weather Service Great Falls MT 403 AM MDT Tue Aug 19 2025 .KEY MESSAGES... - Hot temperatures expected today with temperatures reaching the low to mid 90s across the lower elevations. - Isolated showers and thunderstorms this afternoon and evening, some could produce some gusty winds. - Not as warm after Wednesday through the weekend, but temperatures trend back upwards for the weekend. && .DISCUSSION... - Meteorological Overview: Upper level ridging building across the Western US will bring increasing temperatures to the Treasure State today and Wednesday, with temperatures rising into the 90s for most lower elevation locations this afternoon. While most of us will be dry today, a few isolated showers and thunderstorms are expected to develop across the Plains late this evening. Depending on the timing of these storms, I can’t rule out a few strong to severe wind gusts. However, most of these should push through the area late in the evening as temperatures begin to fall for the night, resulting in an inversion that should keep wind gusts just above the surface. With that said, some localized higher elevations could still see some isolated gusts from these storms. Our upper level ridge will begin to break down on Wednesday as an upper level tough pushes through Alberta, which will keep our temperatures slightly cooler Wednesday afternoon, but will also result in increased wind gusts and a few isolated to scattered showers and thunderstorms in the afternoon. Again, some of the storms may produce some stronger wind gusts, particularly before 8 or 9PM when our inversion will set up again. As we head into the later part of the week, upper level ridging will set up to our west, resulting in northwesterly flow aloft over us and high pressure at the surface. This will keep us fairly dry and calm, with temperatures not quite as warm with highs generally in the 80s across the lower elevations. Ludwig && .AVIATION... 19/06Z TAF Period VFR conditions will persist through the period as high pressure builds over the region. There is around a 15% chance for isolated thunderstorms later in the afternoon on Tuesday which may impact KCTB, KHVR, and KGTF. However, confidence in timing was not high enough to include it in the TAF. -thor Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .FIRE WEATHER... Fire weather concerns will continue through Tuesday and Wednesday with highs in the 90s expected across the plains and valleys across the region. Minimum RH values will range from the single digits to the mid teens with Tuesday expected to be the warmest and driest day of the week. Winds are less of a concern these days, however, an isolated afternoon dry thunderstorm cannot be ruled out which will keep fire weather concerns elevated until a cold front passes through late Wednesday into Thursday. -thor && .PRELIMINARY POINT TEMPS/POPS... GTF 96 60 92 55 / 0 30 0 20 CTB 90 58 86 49 / 10 40 10 0 HLN 96 60 92 56 / 0 20 0 20 BZN 96 54 93 53 / 0 0 20 20 WYS 86 43 85 42 / 0 0 20 20 DLN 92 52 90 50 / 0 0 20 20 HVR 96 62 93 55 / 0 40 0 20 LWT 93 58 88 54 / 0 0 0 40 && .TFX WATCHES/WARNINGS/ADVISORIES... None. && $$ http://www.weather.gov/greatfalls