FPUS65 KTFX 210938 AFPTFX Central and Southwest Montana Area Forecast National Weather Service Great Falls MT 337 AM MDT Mon Sep 21 2026 MTZ301>314-316>318-220000- Central Montana- National Weather Service Great Falls MT 337 AM MDT Mon Sep 21 2026 .TODAY...Sunny. Patchy fog in the morning. Highs 70 to 80...60 to 70 in the mountains. .TONIGHT...Mostly clear. Lows 45 to 50. .TUESDAY...Increasing clouds. Highs 75 to 80...65 to 75 in the mountains. .WEDNESDAY...Mostly clear. Lows 45 to 50. Highs 70 to 80. .THURSDAY...Partly cloudy. Lows 45 to 50. Highs 75 to 85. .FRIDAY...Partly cloudy. Slight chance of rain. Lows 50 to 55. Highs 70 to 80. $$ MTZ315-319>330-220000- Southwest Montana- National Weather Service Great Falls MT 337 AM MDT Mon Sep 21 2026 .TODAY...Sunny. Highs 65 to 75...55 to 65 in the mountains. .TONIGHT...Mostly clear. Lows 40 to 45. .TUESDAY...Mostly cloudy. Highs 65 to 75...55 to 65 in the mountains. .WEDNESDAY...Mostly clear. Lows 40 to 50. Highs 65 to 75. .THURSDAY...Mostly clear. Lows 40 to 50. Highs 70 to 80. .FRIDAY...Partly cloudy. Slight chance of rain. Lows 45 to 50. Highs 65 to 75. $$