FZUS53 KGRB 200741 NSHGRB Nearshore Marine Forecast National Weather Service Green Bay WI 241 AM CDT Mon Apr 20 2026 For waters within five nautical miles of shore on Lake Michigan LMZ521-522-201000- Green Bay south of line from Cedar River to Rock Island Passage and north of a line from Oconto WI to Little Sturgeon Bay WI- Green Bay south of line from Oconto WI to Little Sturgeon Bay WI- 241 AM CDT Mon Apr 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH LATE TONIGHT... .REST OF THE NIGHT...NW wind 5 to 10 kts backing W after midnight. Waves 2 ft or less. Clear. .MONDAY...SW wind 5 to 10 kts backing S mid-day, then increasing to 10 to 20 kts early in the afternoon. Waves 1 to 3 ft. Sunny in the morning then becoming partly cloudy. .MONDAY NIGHT...S wind 15 to 25 kts veering SW 10 to 15 kts after midnight. Waves 2 to 4 ft subsiding to 1 to 3 ft after midnight. Mostly cloudy in the evening then becoming partly cloudy. .TUESDAY...SW wind 5 to 10 kts backing E early in the afternoon. Waves 2 ft or less. Sunny. $$ LMZ541-201000- Rock Island Passage to Sturgeon Bay WI- 241 AM CDT Mon Apr 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH TUESDAY AFTERNOON... .REST OF THE NIGHT...NW wind 5 to 10 kts. Waves 2 ft or less. Clear. .MONDAY...W wind 5 to 10 kts backing SW 10 to 15 kts mid-day, then backing S 15 to 25 kts early in the afternoon. Waves 2 ft or less building to 4 to 7 ft in the afternoon. Sunny in the morning then becoming partly sunny. .MONDAY NIGHT...S wind to 30 kts becoming SW 10 to 20 kts after midnight. Waves 5 to 8 ft. Mostly cloudy. .TUESDAY...S wind 5 to 10 kts backing SE early in the afternoon. Waves 4 to 7 ft subsiding to 2 to 4 ft in the afternoon. Sunny. $$ LMZ542-543-201000- Sturgeon Bay to Two Rivers WI-Two Rivers to Sheboygan WI- 241 AM CDT Mon Apr 20 2026 ...SMALL CRAFT ADVISORY IN EFFECT FROM THIS AFTERNOON THROUGH TUESDAY AFTERNOON... .REST OF THE NIGHT...NE wind 5 to 10 kts backing SW after midnight. Waves 2 ft or less. Clear. .MONDAY...S wind 10 to 15 kts increasing to 15 to 25 kts early in the afternoon. Waves 2 ft or less building to 4 to 7 ft in the afternoon. Sunny in the morning then becoming partly cloudy. .MONDAY NIGHT...S wind to 30 kts decreasing to 10 to 15 kts after midnight. Waves 4 to 7 ft. Mostly cloudy. .TUESDAY...S wind 5 to 10 kts backing SE early in the afternoon. Waves 3 to 5 ft subsiding to 2 to 4 ft in the afternoon. Mostly sunny. $$ See Lake Michigan Open Lake Forecast for Wednesday through Friday. Wave height forecast is for ice free areas.