RECMKX Recreational Boater Forecast for Inland Lakes for Southeast Wisconsin National Weather Service Milwaukee/Sullivan WI 1530 CDT Wed Aug 19 2026 ...Lake Mendota... .TONIGHT... Waves...............Nearly calm. Sky/Weather.........Mostly sunny until 11 PM, then mostly clear. Patchy fog after 2 AM. Min Temperature.....Around 57. Winds...............Northeast winds up to 5 mph in the afternoon becoming light. Water Temperature...68 degrees. UV Index............7 - High. .THURSDAY... Waves...............Nearly calm. Sky/Weather.........Sunny. Patchy fog until 11 AM. Max Temperature.....Around 81. Winds...............Southwest winds up to 5 mph. Water Temperature...68 degrees. UV Index............7 - High. .THURSDAY NIGHT... Waves...............Half foot to 1 foot. Sky/Weather.........Partly cloudy then becoming mostly cloudy. Slight chance of thunderstorms after midnight. Min Temperature.....Lower 60s. Winds...............South winds 5 to 10 mph. .FRIDAY... Waves...............Half foot to 1 foot. Sky/Weather.........Mostly sunny. Chance of showers in the morning. Chance of thunderstorms through the day. Max Temperature.....Lower 80s. Winds...............Southwest winds around 10 mph. .SATURDAY... Waves...............Half foot to 1 foot. Sky/Weather.........Sunny. Max Temperature.....Lower 80s. Winds...............Northwest winds 5 to 10 mph. Sunrise: 06:08 AM CDT Sunset: 07:55 PM CDT $$