SXUS43 KGRB 202012 RECGRB WIZ048-WIZ049-210900- Recreational Forecast for Lake Winnebago National Weather Service Green Bay WI 312 PM CDT Sun Sep 20 2026 .REST OF THE AFTERNOON...Northeast winds 15 to 20 knots. Chance of sprinkles. Waves 2 to 4 feet. Near steady temperature in the lower 60s. .TONIGHT...Northeast winds 15 to 25 knots. Mostly cloudy. Waves 3 to 5 feet. Lows in the mid 50s. .MONDAY...Northeast winds 10 to 15 knots. Mostly cloudy. Waves 2 to 4 feet subsiding to 1 to 3 feet in the afternoon. Highs around 60. .MONDAY NIGHT...Northeast winds 10 to 20 knots. Mostly cloudy. Waves 2 to 4 feet. Lows in the upper 40s. .TUESDAY...Northeast winds 10 to 15 knots. Partly sunny in the morning then clearing. Waves 1 to 3 feet. Highs in the lower 60s. $$