865 FZUS63 KMQT 171401 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 1000 AM EDT Fri Apr 17 2026 For waters beyond 5 nautical miles of shore on Lake Superior. Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum. .SYNOPSIS... A low of around 29.4 inches moves across Lake Superior late this afternoon through this evening. Behind it, ridging builds over the lake, strengthening to about 30.3 inches Sunday night into Monday morning. This ridging quickly gives way to 29.8 inch troughing Monday night into Tuesday morning as a weakening low swings from the Hudson Bay shoreline of far northern Ontario into James Bay. High pressure ridging builds back to 30.2 inches over Lake Superior by Tuesday night. LSZ162-172000- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 1000 AM EDT Fri Apr 17 2026 /900 AM CDT Fri Apr 17 2026/ .REST OF TODAY...East winds 10 to 20 knots backing northeast in the afternoon, then becoming northwest 15 to 25 knots late. A slight chance of rain showers by late morning, then rain showers and a chance of thunderstorms by mid afternoon. Waves 1 to 3 feet building to 3 to 5 feet occasionally to 7 feet. .TONIGHT...West winds 15 to 25 knots increasing to 30 knots with a few gale force gusts to 35 knots possible. A slight chance of rain showers through midnight. Waves subsiding to 2 to 4 feet, then building to 3 to 6 feet occasionally to 8 feet. .SATURDAY...West winds to 30 knots with a few gale force gusts to 35 knots possible diminishing to 20 to 30 knots late. Waves building to 4 to 7 feet occasionally to 9 feet. .SATURDAY NIGHT...Northwest winds 15 to 25 knots. Waves subsiding to 1 to 3 feet. .SUNDAY...Northwest winds 10 to 20 knots becoming west 5 to 15 knots by mid afternoon. Waves subsiding to calm to 2 feet. .SUNDAY NIGHT...Northwest winds 5 to 15 knots veering north after midnight. Waves calm to 2 feet. .MONDAY...South winds 10 to 20 knots becoming southwest 20 to 30 knots. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet. .TUESDAY...West winds 10 to 20 knots becoming northeast 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ263-172000- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 1000 AM EDT Fri Apr 17 2026 ...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY EVENING... .REST OF TODAY...Southeast winds 10 to 20 knots becoming south 15 to 25 knots late. Rain showers likely and a chance of thunderstorms by mid afternoon. Waves 3 to 5 feet occasionally to 7 feet building to 4 to 7 feet occasionally to 9 feet. .TONIGHT...West winds 15 to 25 knots increasing to 20 to 30 knots after midnight. A chance of rain showers and a slight chance of thunderstorms through midnight. Waves subsiding to 3 to 5 feet occasionally to 7 feet, then building to 5 to 8 feet occasionally to 10 feet. .SATURDAY...West winds 20 to 30 knots increasing to gales to 35 knots late. Waves building to 8 to 11 feet occasionally to 14 feet. .SATURDAY NIGHT...Northwest winds 20 to 30 knots diminishing to 15 to 25 knots after midnight. Waves subsiding to 3 to 6 feet occasionally to 8 feet. .SUNDAY...Northwest winds 10 to 20 knots becoming west 5 to 15 knots by mid afternoon. Waves subsiding to calm to 2 feet. .SUNDAY NIGHT...Northwest winds 5 to 15 knots veering north after midnight. Waves calm to 2 feet. .MONDAY...South winds 15 to 25 knots becoming southwest 20 to 30 knots. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .TUESDAY...West winds 15 to 25 knots becoming east 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ264-172000- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 1000 AM EDT Fri Apr 17 2026 ...GALE WARNING IN EFFECT FROM 3 PM EDT THIS AFTERNOON THROUGH THIS EVENING... ...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY EVENING... .REST OF TODAY...Southeast winds 15 to 25 knots increasing to gales to 35 knots. A chance of showers and thunderstorms by mid afternoon. Waves 3 to 6 feet occasionally to 8 feet building to 8 to 11 feet occasionally to 14 feet. .TONIGHT...South gales to 35 knots becoming west 20 to 30 knots after midnight, then veering northwest late. Rain showers and a chance of thunderstorms through midnight, then a slight chance of rain and snow showers after midnight. Waves subsiding to 5 to 8 feet occasionally to 10 feet. .SATURDAY...West winds 20 to 30 knots. Waves building to 8 to 11 feet occasionally to 14 feet. .SATURDAY NIGHT...Northwest winds 20 to 30 knots. Waves subsiding to 5 to 8 feet occasionally to 10 feet. .SUNDAY...Northwest winds 15 to 25 knots. Waves subsiding to 1 to 3 feet. .SUNDAY NIGHT...Northwest winds 5 to 15 knots veering north after midnight. Waves subsiding to calm to 2 feet. .MONDAY...South winds 15 to 25 knots increasing to 20 to 30 knots. Waves building to 5 to 8 feet occasionally to 10 feet. .TUESDAY...West winds 15 to 25 knots becoming northeast 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ265-172000- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 1000 AM EDT Fri Apr 17 2026 ...GALE WARNING IN EFFECT FROM 3 PM EDT THIS AFTERNOON THROUGH THIS EVENING... ...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY EVENING... .REST OF TODAY...Southeast winds 20 to 30 knots increasing to gales to 35 knots late. A slight chance of showers and thunderstorms by mid afternoon. Waves 3 to 5 feet occasionally to 7 feet building to 6 to 9 feet occasionally to 11 feet. .TONIGHT...South gales to 40 knots becoming west gales to 35 knots after midnight. Rain showers and a chance of thunderstorms through midnight, then a chance of rain showers, possibly mixed with snow after midnight. Waves building to 7 to 10 feet occasionally to 13 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .SATURDAY...West gales to 40 knots. Waves building to 6 to 9 feet occasionally to 11 feet. .SATURDAY NIGHT...Northwest gales to 35 knots diminishing to 20 to 30 knots after midnight. Waves subsiding to 4 to 7 feet occasionally to 9 feet. .SUNDAY...Northwest winds 20 to 30 knots diminishing to 15 to 25 knots by mid afternoon. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .SUNDAY NIGHT...Northwest winds 10 to 20 knots. Waves subsiding to calm to 2 feet. .MONDAY...Southeast winds 15 to 25 knots becoming south gales to 35 knots. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .TUESDAY...Northwest winds 15 to 25 knots becoming north 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ266-172000- Lake Superior East of a line from Manitou Island to Marquette MI and West of a line from Grand Marais MI to the US/Canadian Border Beyond 5NM from shore- 1000 AM EDT Fri Apr 17 2026 ...GALE WARNING IN EFFECT FROM 3 PM EDT THIS AFTERNOON THROUGH THIS EVENING... ...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY EVENING... .REST OF TODAY...Southeast winds 20 to 30 knots becoming south gales to 35 knots late. Patchy fog by late morning. A slight chance of rain showers by mid afternoon. Waves 3 to 6 feet occasionally to 8 feet building to 7 to 10 feet occasionally to 13 feet. .TONIGHT...South gales to 40 knots becoming west gales to 35 knots after midnight, then veering northwest late. Rain showers likely and a chance of thunderstorms through midnight, then a chance of rain showers, possibly mixed with snow after midnight. Waves building to 8 to 11 feet occasionally to 14 feet, then subsiding to 5 to 8 feet occasionally to 10 feet. .SATURDAY...Northwest gales to 35 knots backing west in the afternoon. A slight chance of rain showers, snow showers and sleet through early afternoon. Waves building to 10 to 14 feet occasionally to 18 feet. .SATURDAY NIGHT...Northwest gales to 35 knots. A slight chance of snow showers through midnight. Waves subsiding to 8 to 11 feet occasionally to 14 feet. .SUNDAY...Northwest winds 20 to 30 knots. Waves subsiding to 5 to 8 feet occasionally to 10 feet. .SUNDAY NIGHT...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots after midnight. Waves subsiding to 1 to 3 feet. .MONDAY...South winds 20 to 30 knots increasing to gales to 40 knots. Waves subsiding to calm to 2 feet, then building to 8 to 11 feet occasionally to 14 feet. .TUESDAY...West winds 20 to 30 knots becoming north 10 to 20 knots. Waves subsiding to 1 to 3 feet. $$ LSZ267-172000- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 1000 AM EDT Fri Apr 17 2026 ...GALE WATCH IN EFFECT FROM LATE TONIGHT THROUGH SATURDAY EVENING... .REST OF TODAY...Southeast winds 15 to 25 knots increasing to 20 to 30 knots late. Waves 1 to 3 feet building to 4 to 7 feet occasionally to 9 feet. .TONIGHT...Southeast winds 20 to 30 knots veering west late. Rain showers likely through midnight. A chance of thunderstorms. A chance of rain showers, possibly mixed with snow after midnight. Waves subsiding to 3 to 6 feet occasionally to 8 feet, then building to 7 to 10 feet occasionally to 13 feet. .SATURDAY...Northwest gales to 35 knots becoming west gales to 40 knots in the afternoon. A slight chance of rain and snow showers, possibly mixed with sleet through early afternoon. Waves building to 10 to 14 feet occasionally to 18 feet. .SATURDAY NIGHT...West gales to 35 knots veering northwest after midnight. A slight chance of snow showers through midnight. Waves subsiding to 8 to 11 feet occasionally to 14 feet. .SUNDAY...Northwest gales to 35 knots. Waves subsiding to 6 to 9 feet occasionally to 11 feet. .SUNDAY NIGHT...Northwest winds 15 to 25 knots becoming north 5 to 15 knots after midnight. Waves subsiding to 1 to 3 feet. .MONDAY...South winds 10 to 20 knots increasing to gales to 35 knots. Waves subsiding to calm to 2 feet, then building to 6 to 9 feet occasionally to 11 feet. .TUESDAY...West winds 20 to 30 knots becoming northwest 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ261-172000- MAFOR 1715/ Superior West 11210 11220 11736 11630 14640. A chance of thunderstorms this afternoon and evening. Waves 2 to 3 feet building to 3 to 5 feet this afternoon. Waves 3 to 5 feet building to 4 to 7 feet tonight. Waves 4 to 7 feet Saturday morning. Superior North Central...GALE WARNING IN EFFECT...11340 12350 11456 11640 13740. A chance of thunderstorms this evening. Waves 3 to 6 feet building to 7 to 10 feet this afternoon. Waves 7 to 11 feet subsiding to 6 to 9 feet tonight. Waves 6 to 9 feet Saturday morning. Superior South Central...GALE WARNING IN EFFECT...11340 11350 11450 11456 11546 11640 12750. A chance of thunderstorms this evening. Waves 3 to 6 feet building to 5 to 8 feet this afternoon. Waves 6 to 9 feet subsiding to 5 to 8 feet tonight. Waves 6 to 9 feet Saturday morning. Superior East...GALE WARNING IN EFFECT...12330 12340 11356 11546 12740. A chance of thunderstorms tonight. Waves 2 to 4 feet building to 3 to 6 feet this afternoon. Waves 5 to 8 feet tonight. Waves 7 to 11 feet Saturday morning. $$ WFO MQT Experimental modernized open lake forecast is available online at weather.gov/mqt/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes  357 FZUS63 KMKX 171402 GLFLM OPEN LAKE FORECAST for Lake Michigan National Weather Service Milwaukee/Sullivan WI 902 AM CDT Fri Apr 17 2026 FOR WATERS BEYOND FIVE NAUTICAL MILES OF SHORE ON Lake Michigan. Waves are provided as a range of significant wave heights, which is the average of the highest 1/3 of the wave, along with the average height of the highest 10% of the waves which will occasionally be encountered. .SYNOPSIS... Winds will become southerly this morning as a surface low of 29.5 inches approaches from the central plains. Dense fog will continue over the lake through this time. This surface low will quickly move from Omaha to Duluth from this morning into the afternoon. Winds will become gusty and southeasterly tonight, and strong to severe storms will cross the lake as a cold front sweeps through the area. Winds then become northwesterly behind the cold front Saturday morning. Breezy northwesterly winds then continue Saturday through Sunday as the low then races northeast toward Hudson Bay. Winds ease Monday morning as high pressure tracks southeast over the upper Great Lakes. LMZ261-362-364-366-563-565-567-868-172130- Lake Michigan from Seul Choix Point to Rock Island Passage 5 NM offshore to Mid Lake- Lake Michigan South of a line from Seul Choix Point to the Mackinac Bridge and north of a line from Charlevoix MI to South Fox Island 5 NM offshore- Lake Michigan from Charlevoix to Point Betsie MI 5 NM offshore to Mid Lake- Lake Michigan from Point Betsie to Manistee MI 5 NM offshore to Mid Lake- Lake Michigan from Rock Island Passage to Sturgeon Bay WI- Lake Michigan from Sturgeon Bay to Two Rivers WI 5 NM offshore to Mid Lake- Lake Michigan from Two Rivers to Sheboygan WI 5 NM offshore to Mid Lake- Lake Michigan from Pentwater to Manistee MI 5 NM offshore to Mid Lake- 902 AM CDT Fri Apr 17 2026 SHEBOYGAN WI TO PENTWATER MI NORTH... ...DENSE FOG ADVISORY IN EFFECT UNTIL 7 PM CDT THIS EVENING... .REST OF TODAY...Southeast winds 10 to 15 kt increasing to 30 kt. Widespread dense fog. Waves 1 to 2 ft building to 4 to 6 ft occasionally to 8 ft. .TONIGHT...Southeast winds to 30 kt veering to southwest 15 to 25 kt. Patchy fog. Rain showers with a chance of thunderstorms in the evening, then chance of rain showers and thunderstorms overnight. Waves 5 to 8 ft occasionally to 10 ft. .SATURDAY...Northwest winds to 30 kt becoming west 15 to 25 kt. Chance of rain showers in the morning. Waves 4 to 7 ft occasionally to 9 ft subsiding to 3 to 5 ft. .SATURDAY NIGHT...Northwest winds 15 to 25 kt. Waves 4 to 6 ft occasionally to 8 ft. .SUNDAY...Northwest winds to 30 kt. Waves 3 to 5 ft. .SUNDAY NIGHT...North winds 15 to 25 kt diminishing to 10 to 20 kt. Waves 2 to 4 ft. .MONDAY...Southwest winds 10 to 15 kt becoming south 10 to 20 kt. Waves 1 to 2 ft building to 2 to 4 ft. .TUESDAY...Southwest winds to 30 kt diminishing to 15 to 25 kt. Waves 7 to 10 ft occasionally to 13 ft. $$ LMZ080-669-671-673-675-777-779-870-872-874-876-878-172130- Lake Michigan from Michigan City IN to St. Joseph MI 5 NM offshore to Mid Lake- Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore to Mid Lake- Lake Michigan from Port Washington to North Point Light WI 5 NM offshore to Mid Lake- Lake Michigan from North Point Light to Wind Point WI 5 NM offshore to Mid Lake- Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM offshore to Mid Lake- Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM offshore to Mid Lake- Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM offshore to Mid Lake- Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid Lake- Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to Mid Lake- Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid Lake- Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid Lake- Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to Mid Lake- 902 AM CDT Fri Apr 17 2026 SHEBOYGAN WI TO PENTWATER MI SOUTH... ...DENSE FOG ADVISORY IN EFFECT UNTIL 7 PM CDT THIS EVENING... .REST OF TODAY...Southeast winds 10 to 15 kt increasing to 30 kt. Widespread dense fog. Waves 1 ft or less building to 4 to 6 ft occasionally to 8 ft. .TONIGHT...South winds to 30 kt veering to southwest 15 to 25 kt. Patchy fog. Rain showers with a chance of thunderstorms in the evening, then chance of rain showers and thunderstorms overnight. Waves 4 to 7 ft occasionally to 9 ft. .SATURDAY...West winds to 30 kt diminishing to 10 to 20 kt. Chance of rain showers in the morning. Waves 4 to 7 ft occasionally to 9 ft subsiding to 4 to 6 ft occasionally to 8 ft. .SATURDAY NIGHT...West winds 15 to 25 kt. Waves 4 to 7 ft occasionally to 9 ft. .SUNDAY...Northwest winds 15 to 25 kt. Waves 4 to 6 ft occasionally to 8 ft. .SUNDAY NIGHT...North winds 10 to 20 kt diminishing to 10 to 15 kt. Waves 2 to 4 ft subsiding to 1 to 3 ft. .MONDAY...Southeast winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 2 ft building to 2 to 4 ft. .TUESDAY...South winds to 30 kt diminishing to 15 to 25 kt. Waves 6 to 9 ft occasionally to 12 ft. $$ LMZ761-172130- MAFOR 1716/ MICHIGAN NORTH 11434 11344 11340 19344 12446 11530 11630 11730. A chance of thunderstorms tonight. Waves 1 to 3 feet building to 3 to 5 feet this afternoon. Waves 4 to 7 feet subsiding to 3 to 6 feet tonight. Waves 3 to 6 feet Saturday morning. MICHIGAN SOUTH 11334 11344 11340 12446 11530 11630 11730. A chance of thunderstorms tonight. Waves 1 to 3 feet building to 3 to 5 feet this afternoon. Waves 3 to 6 feet tonight and Saturday morning. $$ Cronce Experimental modernized open lake forecast is available online at weather.gov/mkx/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes  647 FZUS61 KBUF 171410 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1009 AM EDT Fri Apr 17 2026 For waters beyond five nautical miles of shore on Lake Ontario Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum. .SYNOPSIS...A 30.0 inch high over the Lake this evening will slide east into New England tonight. Meanwhile, a 29.4 inch low near Lake Superior this evening will move to James Bay and deepen to 29.0 inches Saturday, while pushing a trailing strong cold front across the Lake later Saturday and Saturday evening. A 30.4 inch high will then settle southeastward across the Great Lakes Sunday through Monday night, before sliding off the mid-Atlantic coast Tuesday. A 29.4 inch low over lower Hudson Bay Tuesday, will weaken to 29.9 inches by Wednesday, while pushing an attendant weak cold front across the Lake Tuesday night. A 30.2 inch high will then build across the Great Lakes region Wednesday and Thursday. LOZ062-172100- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1009 AM EDT Fri Apr 17 2026 .THIS AFTERNOON...North winds less than 10 knots becoming east. Areas of fog. Waves 1 foot or less. .TONIGHT...East winds 10 knots or less becoming southeast. Waves 1 foot or less. .SATURDAY...Southeast winds 10 to 15 knots becoming southwest 15 to 20 knots. A chance of showers in the morning, then showers in the afternoon. Waves 1 to 3 feet building to 2 to 4 feet. .SATURDAY NIGHT...West winds 15 to 20 knots becoming northwest. Rain showers in the evening, then rain showers likely overnight. Waves 3 to 5 feet. .SUNDAY...West winds 15 to 20 knots becoming northwest. A chance of rain showers. Waves 3 to 5 feet. .MONDAY...Northwest winds 15 to 20 knots becoming southwest 5 to 15 knots. Waves 3 to 5 feet subsiding to 1 to 3 feet. .TUESDAY...South winds 15 to 20 knots becoming west 10 to 15 knots. Waves 1 to 3 feet building to 2 to 4 feet. $$ LOZ063>065-172100- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1009 AM EDT Fri Apr 17 2026 .THIS AFTERNOON...North winds 5 to 10 knots becoming northwest. Patchy fog. Waves 1 foot or less. .TONIGHT...West winds 10 knots or less becoming southeast 10 to 15 knots. Waves 1 foot or less. .SATURDAY...Southeast winds 15 to 20 knots becoming south. Showers in the afternoon. Waves 1 to 3 feet building to 3 to 5 feet. .SATURDAY NIGHT...South winds 15 to 20 knots becoming west. Rain showers. Waves 3 to 5 feet. .SUNDAY...West winds 15 to 25 knots becoming northwest. Rain showers during the day. Waves 3 to 6 feet building to 4 to 7 feet. Waves occasionally around 9 feet. .MONDAY...Northwest winds 15 to 20 knots becoming west. Waves 3 to 6 feet subsiding to 2 to 4 feet. .TUESDAY...South winds 15 to 20 knots becoming southwest. A chance of rain showers Tuesday night. Waves 1 to 3 feet building to 2 to 4 feet. $$ LOZ061-172100- MAFOR 1715/ ONTARIO WEST 1/2 11100 14200 11300 12310. Waves 1 foot or less this afternoon and tonight. Waves 1 to 3 feet Saturday morning. ONTARIO EAST 1/2 11800 12700 13300 11310 11320. Waves 1 foot or less this afternoon and tonight. Waves 1 to 3 feet building to 2 to 4 feet Saturday morning. $$  441 FZUS61 KBUF 171411 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 1011 AM EDT Fri Apr 17 2026 SLZ022-024-172100- Saint Lawrence River from Cape Vincent to Saint Regis 1011 AM EDT Fri Apr 17 2026 .THIS AFTERNOON...Northeast winds 10 knots or less. Becoming mostly sunny. .TONIGHT...Northeast winds less than 10 knots. Mainly clear through the early overnight, then becoming partly cloudy. .SATURDAY...Southeast winds 5 to 15 knots becoming south. A chance of showers in the afternoon. .SATURDAY NIGHT...South winds 10 to 15 knots becoming west. Showers. .SUNDAY...West winds 5 to 15 knots becoming northwest. Rain showers during the day, then a chance of rain showers Sunday night. .MONDAY...Northwest winds 10 knots or less becoming southwest. Mostly cloudy, then clearing. .TUESDAY...South winds 5 to 10 knots becoming southwest. A chance of rain showers. $$