SXUS45 KMSO 292330 RECGPI Recreation Forecast for Flathead Lake National Weather Service Missoula MT 505 PM MDT Fri May 29 2026 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. .Tonight...Mostly cloudy. A chance of showers and a slight chance of thunderstorms early in the evening, then a chance of rain late in the evening. Lows in the lower 50s. Variable winds up to 10 mph. Chance of precipitation 50 percent. Waves less than 1 foot. .SATURDAY...Mostly cloudy. A slight chance of rain in the morning, then a chance of rain in the afternoon. Highs around 60 . Variable winds up to 10 mph. Chance of rain 50 percent. Waves less than 1 foot. .SATURDAY NIGHT...Rain. Lows in the upper 40s. Variable winds up to 10 mph. Chance of rain 80 percent. Waves less than 1 foot. .SUNDAY...Rain likely in the morning, then rain in the afternoon. Highs in the lower 50s. Variable winds up to 10 mph. Chance of rain 90 percent. Waves less than 1 foot.