SXUS45 KMSO 121230 RECGPI Recreation Forecast for Flathead Lake National Weather Service Missoula MT 506 AM MST Fri Dec 12 2025 Note: The experimental wave height forecasts are representative of the mid lake waters and downwind shores. Wave heights may be significantly less on upwind shores. .Today...Patchy fog until late afternoon. A slight chance of snow in the morning. Rain through the day. No snow accumulation. Highs in the upper 40s. Variable winds up to 10 mph becoming south around 15 mph in the afternoon. Chance of precipitation 90 percent. Waves less than 1 foot. .Tonight...Breezy. Cloudy with a 50 percent chance of rain. Lows in the lower 40s. South winds 15 to 20 mph. Waves around 1 foot... locally up to 2 feet. .SATURDAY...Cloudy with a 40 percent chance of rain in the morning, then partly sunny in the afternoon. Highs in the upper 40s. Variable winds up to 10 mph. Waves around 1 foot...locally up to 2 feet. .SATURDAY NIGHT...Partly cloudy. Lows in the upper 30s. Variable winds up to 10 mph. Waves less than 1 foot. .SUNDAY...Mostly sunny. Highs in the upper 40s. Variable winds up to 10 mph. Waves around 1 foot...locally up to 2 feet.