189 FZUS63 KMQT 231401 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 1000 AM EDT Sun Aug 23 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... This morning, a 29.7 inch low is along the Quebec/Ontario line while 30.1 inch high pressure extends from northwestern Ontario to Iowa. Little movement is expected with only a slight weakening of both pressure centers through today and tonight. By Monday night, the low weakens to 29.8 inches as it fully moves into Quebec, allowing the high to also weaken to 30.0 inches and settle over the Upper Great Lakes. Meanwhile, 29.8 inch low pressure moves over Lake Winnipeg. These systems all shift east slowly through Wednesday afternoon, when the weak high moves over New England as the 29.7 inch low moves over Lake Superior. By Thursday afternoon, the low will deepen to 29.6 inches over western Quebec as a 30.2 inch high moves over northern Manitoba. This high will extend 30.1 inch ridging over Lake Superior Friday into the weekend. LSZ162-232000- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 1000 AM EDT Sun Aug 23 2026 /900 AM CDT Sun Aug 23 2026/ .REST OF TODAY...North winds 5 to 15 knots backing southwest in the afternoon. Waves calm to 2 feet. .TONIGHT...Southwest winds 5 to 15 knots veering northwest after midnight, then veering north late. Waves calm to 2 feet. .MONDAY...North winds 5 to 15 knots veering south in the afternoon. Waves calm to 2 feet. .MONDAY NIGHT...Southeast winds 5 to 15 knots becoming south less than 10 knots after midnight. A slight chance of showers after midnight. Waves calm to 2 feet. .TUESDAY...South winds 5 to 15 knots backing east by mid afternoon. A chance of showers through early afternoon, then showers likely and a slight chance of thunderstorms by mid afternoon. Waves calm to 2 feet. .TUESDAY NIGHT...East winds 5 to 15 knots veering west after midnight. Showers likely through midnight. A chance of thunderstorms. A chance of showers after midnight. Waves calm to 2 feet. .WEDNESDAY...West winds 5 to 15 knots becoming northwest 10 to 20 knots. A chance of showers. Waves calm to 2 feet. .THURSDAY...Northwest winds 10 to 20 knots becoming north 5 to 15 knots. Waves calm to 2 feet. $$ LSZ263-232000- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 1000 AM EDT Sun Aug 23 2026 .REST OF TODAY...North winds 10 to 20 knots diminishing to 5 to 15 knots in the afternoon, then backing west late. Waves 1 to 3 feet subsiding to calm to 2 feet. .TONIGHT...West winds 5 to 15 knots veering north late. Waves calm to 2 feet. .MONDAY...North winds 5 to 15 knots backing northwest in the afternoon, then backing southwest late. Waves calm to 2 feet. .MONDAY NIGHT...Southwest winds 5 to 15 knots backing south after midnight. Waves calm to 2 feet. .TUESDAY...South winds 5 to 15 knots backing east by mid afternoon. A slight chance of showers through early afternoon, then showers likely and a slight chance of thunderstorms by mid afternoon. Waves calm to 2 feet. .TUESDAY NIGHT...Southeast winds 5 to 15 knots veering south after midnight. Showers and a chance of thunderstorms. Waves calm to 2 feet. .WEDNESDAY...West winds 10 to 20 knots veering northwest. A chance of showers. Waves calm to 2 feet. .THURSDAY...Northwest winds 10 to 20 knots becoming north 5 to 15 knots. Waves calm to 2 feet. $$ LSZ264-232000- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 1000 AM EDT Sun Aug 23 2026 .REST OF TODAY...North winds 10 to 20 knots backing northwest late. Waves 3 to 5 feet occasionally to 7 feet subsiding to 1 to 3 feet. .TONIGHT...Northwest winds 10 to 20 knots becoming north 5 to 15 knots late. Waves 1 to 3 feet. .MONDAY...North winds 5 to 15 knots backing west late. Waves subsiding to calm to 2 feet. .MONDAY NIGHT...West winds 5 to 15 knots. Waves calm to 2 feet. .TUESDAY...South winds 5 to 15 knots backing southeast by mid afternoon. A slight chance of showers by mid afternoon. Waves calm to 2 feet. .TUESDAY NIGHT...Southeast winds 10 to 20 knots becoming south 5 to 15 knots after midnight. Showers and a chance of thunderstorms. Waves building to 1 to 3 feet. .WEDNESDAY...West winds 5 to 15 knots becoming northwest 10 to 20 knots. A chance of showers. Waves subsiding to calm to 2 feet. .THURSDAY...Northwest winds 15 to 25 knots becoming north 5 to 15 knots. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. $$ LSZ265-232000- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 1000 AM EDT Sun Aug 23 2026 .REST OF TODAY...North winds 20 to 30 knots backing northwest late. Isolated showers. Waves 3 to 6 feet occasionally to 8 feet. .TONIGHT...Northwest winds 15 to 25 knots. Waves subsiding to 2 to 4 feet. .MONDAY...North winds 10 to 20 knots backing northwest in the afternoon, then diminishing to 5 to 15 knots late. Waves subsiding to 1 to 3 feet. .MONDAY NIGHT...West winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .TUESDAY...South winds 5 to 15 knots becoming southeast 10 to 20 knots by mid afternoon. A chance of showers by mid afternoon. Waves calm to 2 feet. .TUESDAY NIGHT...Southeast winds 15 to 25 knots veering south after midnight. Showers and a chance of thunderstorms. Waves building to 1 to 3 feet. .WEDNESDAY...West winds 10 to 20 knots becoming northwest 15 to 25 knots. Showers likely. Waves subsiding to calm to 2 feet, then building to 2 to 4 feet. .THURSDAY...Northwest gales to 35 knots diminishing to 15 to 25 knots. Waves building to 3 to 6 feet occasionally to 8 feet, then subsiding to calm to 2 feet. $$ LSZ266-232000- 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 Sun Aug 23 2026 .REST OF TODAY...North winds 20 to 30 knots backing northwest late. Isolated showers. Waves 4 to 7 feet occasionally to 9 feet. .TONIGHT...Northwest winds 20 to 30 knots diminishing to 15 to 25 knots after midnight, then veering north late. Waves subsiding to 3 to 6 feet occasionally to 8 feet, then building to 4 to 7 feet occasionally to 9 feet. .MONDAY...North winds 15 to 25 knots backing northwest in the afternoon, then diminishing to 10 to 20 knots late. Waves subsiding to 2 to 4 feet. .MONDAY NIGHT...Northwest winds 10 to 20 knots becoming west 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .TUESDAY...South winds 5 to 15 knots becoming southeast 10 to 20 knots by mid afternoon. A slight chance of showers by mid afternoon. Waves calm to 2 feet. .TUESDAY NIGHT...Southeast winds 15 to 25 knots veering south after midnight. A chance of showers through midnight. A chance of thunderstorms. Showers after midnight. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .WEDNESDAY...South winds 10 to 20 knots becoming northwest 15 to 25 knots. Showers likely. Waves subsiding to calm to 2 feet, then building to 2 to 4 feet. .THURSDAY...Northwest gales to 35 knots becoming north 15 to 25 knots. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 1 to 3 feet. $$ LSZ267-232000- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadianborder- 1000 AM EDT Sun Aug 23 2026 .REST OF TODAY...Northwest winds 20 to 30 knots increasing to 30 knots with a few gale force gusts to 35 knots possible in the afternoon. Isolated showers. Waves 3 to 6 feet occasionally to 8 feet building to 4 to 7 feet occasionally to 9 feet. .TONIGHT...Northwest winds to 30 knots with a few gale force gusts to 35 knots possible becoming north 20 to 30 knots late. Waves building to 4 to 8 feet occasionally to 10 feet. .MONDAY...North winds 20 to 30 knots becoming northwest 15 to 25 knots in the afternoon. Waves subsiding to 2 to 4 feet. .MONDAY NIGHT...Northwest winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .TUESDAY...West winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .TUESDAY NIGHT...Southeast winds 5 to 15 knots becoming south 15 to 25 knots after midnight. A chance of thunderstorms. Showers likely after midnight. Waves building to 2 to 4 feet. .WEDNESDAY...South winds 10 to 20 knots veering west. Showers. A chance of thunderstorms. A chance of showers. Waves subsiding to calm to 2 feet. .THURSDAY...Northwest winds 15 to 25 knots. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. $$ LSZ261-232000- MAFOR 2315/ Superior West 11810 11500 11510 11500 11600 11700 12800. Waves 2 feet or less. Superior North Central 11830 14720 11820 12810. Waves 2 to 4 feet. Superior South Central 12840 13740 11730 12830. Waves 3 to 6 feet. Superior East 14740 11730 11740 12830. Waves 4 to 6 feet. $$ 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  274 FZUS61 KBUF 231402 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1002 AM EDT Sun Aug 23 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 cold front continues to sweep eastward across Lake Ontario through this early afternoon. Behind the front, a trough averaging 29.8 inches lingers over Lake Ontario through Monday. On Tuesday through Wednesday, a ridge averaging 30.1 inches builds from the western and central Great Lakes. The ridge should begin to exit eastward on Thursday and allow a warm front to sweep northeastward across Lake Ontario. On Friday, a cold front should sweep eastward across the lake and be followed by a high pressure ridge averaging 30.0 inches and building from the Upper Midwest. LOZ062-232100- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1002 AM EDT Sun Aug 23 2026 .REST OF TODAY...West winds 15 to 25 knots. A chance of waterspouts. A chance of showers late this morning, then showers with a chance of thunderstorms this afternoon. Waves 3 to 6 feet. .TONIGHT...West winds 15 to 25 knots. A chance of waterspouts. Showers likely with a chance of thunderstorms early, then a chance of showers. Showers likely late. Waves 4 to 6 feet. .MONDAY...Southwest winds to 30 knots becoming west. A chance of waterspouts. Showers. Waves 4 to 7 feet building to 6 to 9 feet. Waves occasionally around 11 feet. .MONDAY NIGHT...West winds 15 to 25 knots. A chance of waterspouts. Showers likely in the evening, then a chance of showers overnight. Waves 5 to 8 feet subsiding to 3 to 6 feet. Waves occasionally around 10 feet. .TUESDAY...West winds 15 to 20 knots becoming northwest and diminishing to less than 10 knots. A chance of waterspouts during the day. A chance of showers during the day. Waves 3 to 5 feet subsiding to 1 foot or less. .WEDNESDAY...Southwest winds 10 knots or less becoming south. Waves 1 foot or less. .THURSDAY...South winds 5 to 10 knots becoming southwest. A chance of showers and thunderstorms. Waves 2 feet or less. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-232100- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1002 AM EDT Sun Aug 23 2026 .REST OF TODAY...Southwest winds 15 to 20 knots becoming west and increasing to 30 knots. A chance of waterspouts. A chance of showers and thunderstorms, then showers with a chance of thunderstorms late. Waves 2 to 4 feet building to 4 to 7 feet. Waves occasionally around 9 feet. .TONIGHT...West winds 15 to 25 knots becoming southwest. A chance of waterspouts. Showers with a chance of thunderstorms in the evening, then showers after midnight. Waves 4 to 7 feet. Waves occasionally around 9 feet. .MONDAY...Southwest winds 15 to 25 knots increasing to 30 knots. A chance of waterspouts. Showers in the morning, then showers with a chance of thunderstorms in the afternoon. Waves 3 to 6 feet building to 6 to 9 feet. Waves occasionally around 11 feet. .MONDAY NIGHT...Southwest winds 15 to 25 knots becoming west. A chance of waterspouts. Showers with a chance of thunderstorms in the evening, then showers overnight. Waves 5 to 9 feet subsiding to 4 to 7 feet. Waves occasionally around 11 feet. .TUESDAY...West winds 15 to 20 knots becoming northwest 5 to 15 knots. A chance of waterspouts during the day. Showers during the day. Waves 3 to 6 feet subsiding to 1 to 3 feet. .WEDNESDAY...West winds 5 to 15 knots becoming southeast. Waves 2 feet or less. .THURSDAY...South winds 15 to 20 knots becoming southwest 10 to 15 knots. A chance of showers and thunderstorms during the day, then showers likely with a chance of thunderstorms Thursday night. Waves 1 to 3 feet. Winds and waves higher in and near thunderstorms. $$ LOZ061-232100- MAFOR 2315/ ONTARIO WEST 1/2 11620 12636 13620 12536. A chance of waterspouts. A chance of thunderstorms this afternoon and evening. Waves 2 to 4 feet building to 4 to 7 feet, and occasionally around 9 feet this afternoon. Waves 4 to 7 feet, and occasionally around 9 feet tonight and Monday morning. ONTARIO EAST 1/2 11520 11620 12636 11526 12520 11536. A chance of waterspouts. A chance of thunderstorms this afternoon and evening. Waves 2 to 4 feet building to 4 to 7 feet, and occasionally around 9 feet this afternoon. Waves 4 to 7 feet, and occasionally around 9 feet tonight. Waves 3 to 6 feet Monday morning. $$  288 FZUS61 KBUF 231403 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 1002 AM EDT Sun Aug 23 2026 SLZ022-024-232100- Saint Lawrence River from Cape Vincent to Saint Regis 1002 AM EDT Sun Aug 23 2026 .THIS AFTERNOON...South winds 10 to 15 knots becoming southwest. Showers likely with a chance of thunderstorms. .TONIGHT...Southwest winds 5 to 15 knots. A chance of showers and thunderstorms early, then a chance of showers. Showers likely late. .MONDAY...South winds 5 to 15 knots becoming southwest. Showers in the morning, then showers with a chance of thunderstorms in the afternoon. .MONDAY NIGHT...Southwest winds 5 to 15 knots. Showers with a chance of thunderstorms in the evening, then showers overnight. .TUESDAY...West winds 10 knots or less. A chance of showers. .WEDNESDAY...Southwest winds 10 knots or less becoming south. Partly cloudy. .THURSDAY...South winds 5 to 10 knots. A chance of showers and thunderstorms during the day, then showers likely with a chance of thunderstorms Thursday night. Winds and waves higher in and near thunderstorms. $$  359 FZUS61 KCLE 231421 GLFLE Open Lake Forecast for Lake Erie National Weather Service Cleveland OH 1021 AM EDT Sun Aug 23 2026 For waters beyond five nautical miles of shore on Lake Erie Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum. .SYNOPSIS... A trough averaging 29.80 will linger over the eastern Great Lakes through Monday morning. High pressure 30.00 inches will gradually build into the region Monday afternoon through Tuesday night before departing to the east on Wednesday. Low pressure 29.80 inches and a trailing cold front will move across the Great Lakes late Wednesday through Thursday. LEZ162-163-232015- Detroit River Lt. to Maumee Bay OH to Reno Beach OH beyond 5NM offshoreline to US-Canadian border- Reno Beach to The Islands OH beyond 5NM off shoreline to US- Canadian border- 1021 AM EDT Sun Aug 23 2026 .THIS AFTERNOON...Northwest winds 15 to 20 knots becoming west. A chance of waterspouts late. A slight chance of showers and thunderstorms late. Waves 2 to 4 feet subsiding to 1 to 3 feet. .TONIGHT...West winds 15 to 20 knots becoming northwest. A chance of waterspouts early. A slight chance of showers and thunderstorms early. Waves 2 to 4 feet subsiding to 1 to 3 feet. .MONDAY...Northwest winds 15 to 20 knots becoming west. Waves 1 to 3 feet building to 2 to 4 feet. .MONDAY NIGHT...West winds 15 to 20 knots becoming northwest and diminishing to around 10 knots. Waves 1 to 3 feet. .TUESDAY...Northwest winds 10 knots or less becoming southwest. Waves 1 foot or less. .WEDNESDAY...Southwest winds 5 to 15 knots. A chance of showers Wednesday night. Waves 2 feet or less. .THURSDAY...Southwest winds 5 to 15 knots becoming northwest. A chance of showers and thunderstorms during the day. Waves 1 foot or less. Winds and waves higher in and near thunderstorms. $$ LEZ164-165-232015- The Islands to Vermilion OH beyond 5 nm off shoreline to US- Canadian border- Vermilion to Avon Point OH beyond 5 nm off shoreline to US- Canadian border- 1021 AM EDT Sun Aug 23 2026 .THIS AFTERNOON...Northwest winds 15 to 20 knots becoming west. A chance of waterspouts late. A slight chance of showers and thunderstorms late. Waves 3 to 5 feet subsiding to 2 to 4 feet. .TONIGHT...West winds 15 to 20 knots becoming northwest. A chance of waterspouts through the early overnight. A chance of showers and thunderstorms in the evening, then a slight chance of showers after midnight. Waves 3 to 5 feet. .MONDAY...Northwest winds 15 to 20 knots becoming west. Waves 2 to 4 feet building to 3 to 5 feet. .MONDAY NIGHT...West winds 15 to 20 knots becoming northwest 10 to 15 knots. Waves 3 to 5 feet subsiding to 1 to 3 feet. .TUESDAY...Northwest winds 10 knots or less becoming southwest. Waves 1 foot or less. .WEDNESDAY...Southwest winds 5 to 15 knots becoming south. A chance of showers and thunderstorms Wednesday night. Waves 2 feet or less. .THURSDAY...Southwest winds 5 to 15 knots becoming northwest. A chance of showers and thunderstorms during the day, then a chance of showers Thursday night. Waves 2 feet or less. Winds and waves higher in and near thunderstorms. $$ LEZ061-166>169-232015- Ripley to Buffalo NY extending from 5NM off shoreline to US- Canadian border- Avon Point to Willowick OH beyond 5 nm off shoreline to US- Canadian border-Willowick to Geneva-on-the- Lake OH beyond 5NM off shoreline to US-Canadian border-Geneva-on- the-Lake to Conneaut OH beyond 5 nm off shoreline to US- Canadian border- Conneaut OH to Ripley NY beyond 5 nm off shoreline to US- Canadian border- 1021 AM EDT Sun Aug 23 2026 .THIS AFTERNOON...West winds 15 to 25 knots. A chance of waterspouts. A chance of showers and thunderstorms. Waves 4 to 6 feet. .TONIGHT...West winds 15 to 20 knots becoming northwest. A chance of waterspouts. Showers with a chance of thunderstorms in the evening, then a chance of showers and thunderstorms after midnight. A chance of showers with a slight chance of thunderstorms late. Waves 3 to 6 feet. .MONDAY...West winds 15 to 25 knots. A chance of waterspouts. A chance of showers. Waves 3 to 6 feet building to 5 to 7 feet. Waves occasionally around 9 feet. .MONDAY NIGHT...West winds 15 to 25 knots becoming northwest and diminishing to 10 to 15 knots. A chance of showers in the evening. A chance of waterspouts. Waves 4 to 7 feet subsiding to 1 to 3 feet. Waves occasionally around 9 feet. .TUESDAY...Northwest winds 5 to 15 knots becoming southwest. Waves 1 to 3 feet subsiding to 1 foot or less. .WEDNESDAY...Southwest winds 5 to 15 knots becoming south. A chance of showers Wednesday night. Waves 2 feet or less. .THURSDAY...South winds 5 to 15 knots becoming west. A chance of showers and thunderstorms during the day, then a chance of showers Thursday night. Waves 1 to 3 feet. Winds and waves higher in and near thunderstorms. $$ LEZ161-232015- MAFOR 2315/ ERIE WEST 1/3 11720 12620 14720 11620. A chance of waterspouts this afternoon and evening. A chance of showers and thunderstorms this evening. Waves 3 to 5 feet subsiding to 2 to 4 feet this afternoon and tonight. Waves 2 to 4 feet building to 3 to 5 feet Monday morning. ERIE CENTRAL 1/3 11720 12620 11726 12720 12620. A chance of waterspouts. A chance of thunderstorms this evening. Waves 3 to 6 feet. ERIE EAST 1/3 11620 11630 11620 11626 11726 12620 11626. A chance of waterspouts. A chance of thunderstorms this afternoon and tonight. Waves 3 to 6 feet. $$