335 FZUS63 KMQT 092001 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 401 PM EDT Thu Jul 9 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... Weak high pressure of 30.0 inches extends over Lake Superior from Hudson Bay and northern Ontario tonight into Friday. High pressure builds to 30.1 to 30.2 inches over the lake this weekend as the high shifts south to the Lower Great Lakes through Sunday. A strong low of around 29.3 inches looks to cross into Hudson Bay early next week. LSZ162-100800- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 401 PM EDT Thu Jul 9 2026 /301 PM CDT Thu Jul 9 2026/ .LATE THIS AFTERNOON...North winds 5 to 15 knots. Waves calm to 2 feet. .TONIGHT...North winds less than 10 knots. Patchy fog. Waves calm to 2 feet. .FRIDAY...North winds less than 10 knots becoming northeast 5 to 15 knots in the afternoon, then veering east late. Waves calm to 2 feet. .FRIDAY NIGHT...Northeast winds 5 to 15 knots diminishing to less than 10 knots after midnight, then backing north late. A slight chance of showers and thunderstorms after midnight. Waves calm to 2 feet. .SATURDAY...South winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...East winds less than 10 knots becoming southwest 5 to 15 knots after midnight. Waves calm to 2 feet. .SUNDAY...Southwest winds 5 to 15 knots increasing to 10 to 20 knots by mid afternoon. Waves calm to 2 feet. .SUNDAY NIGHT...Southwest winds 10 to 20 knots. Waves building to 1 to 3 feet. .MONDAY...Southwest winds 20 to 30 knots. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet. .TUESDAY...Southwest winds 15 to 25 knots becoming north 10 to 20 knots. Waves subsiding to calm to 2 feet. $$ LSZ263-100800- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 401 PM EDT Thu Jul 9 2026 .LATE THIS AFTERNOON...Northeast winds less than 10 knots. Waves calm to 2 feet. .TONIGHT...North winds less than 10 knots backing west after midnight, then backing east late. Patchy fog after midnight. Waves calm to 2 feet. .FRIDAY...East winds less than 10 knots backing northeast in the afternoon, then veering east late. Patchy dense fog through early afternoon. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 5 to 15 knots veering southeast after midnight, then backing east late. A slight chance of showers and thunderstorms after midnight. Waves calm to 2 feet. .SATURDAY...Southwest winds 5 to 15 knots backing southeast by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 5 to 15 knots veering southwest after midnight. Waves calm to 2 feet. .SUNDAY...Southwest winds 5 to 15 knots increasing to 10 to 20 knots by mid afternoon. Waves building to 1 to 3 feet. .SUNDAY NIGHT...Southwest winds 15 to 25 knots. Waves building to 2 to 4 feet. .MONDAY...Southwest winds 20 to 30 knots. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .TUESDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots. Waves subsiding to calm to 2 feet. $$ LSZ264-100800- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 401 PM EDT Thu Jul 9 2026 .LATE THIS AFTERNOON...West winds less than 10 knots. Waves calm to 2 feet. .TONIGHT...West winds less than 10 knots veering northwest after midnight, then veering northeast late. Patchy fog after midnight. Waves calm to 2 feet. .FRIDAY...East winds less than 10 knots veering southeast in the afternoon, then increasing to 5 to 15 knots late. Patchy fog through early afternoon. Waves calm to 2 feet. .FRIDAY NIGHT...Southeast winds 5 to 15 knots. A chance of showers. A slight chance of thunderstorms after midnight. Waves calm to 2 feet. .SATURDAY...Southeast winds less than 10 knots. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds less than 10 knots becoming southwest 5 to 15 knots after midnight. Waves calm to 2 feet. .SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet. .SUNDAY NIGHT...Southwest winds 10 to 20 knots increasing to 15 to 25 knots after midnight. Waves building to 2 to 4 feet. .MONDAY...Southwest winds 15 to 25 knots becoming west 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 20 to 30 knots diminishing to 10 to 20 knots. Waves subsiding to calm to 2 feet. $$ LSZ265-100800- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 401 PM EDT Thu Jul 9 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 8 AM EDT FRIDAY... .LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to 2 feet. .TONIGHT...West winds 5 to 15 knots veering north late. Patchy fog after midnight. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots veering southeast late. Waves calm to 2 feet. .FRIDAY NIGHT...Southeast winds 5 to 15 knots increasing to 10 to 20 knots after midnight. A slight chance of showers and thunderstorms after midnight. Waves calm to 2 feet. .SATURDAY...Southeast winds 5 to 15 knots becoming east 10 to 20 knots by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 5 to 15 knots veering south after midnight. Waves calm to 2 feet. .SUNDAY...Southwest winds 10 to 20 knots backing southeast by mid afternoon. Waves calm to 2 feet. .SUNDAY NIGHT...South winds 10 to 20 knots becoming southwest 15 to 25 knots after midnight. Waves building to 1 to 3 feet. .MONDAY...Southwest winds 10 to 20 knots increasing to 20 to 30 knots. Waves subsiding to calm to 2 feet, then building to 3 to 5 feet occasionally to 7 feet. .TUESDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots. Waves subsiding to calm to 2 feet. $$ LSZ266-100800- 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- 401 PM EDT Thu Jul 9 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 8 AM EDT FRIDAY... .LATE THIS AFTERNOON...Northwest winds 5 to 15 knots. Waves calm to 2 feet. .TONIGHT...Northwest winds 5 to 15 knots veering north late. Patchy fog through midnight. Areas of dense fog after midnight. Waves calm to 2 feet. .FRIDAY...Northeast winds 5 to 15 knots veering southeast in the afternoon. Areas of dense fog through early afternoon. Waves calm to 2 feet. .FRIDAY NIGHT...Southeast winds 5 to 15 knots. A slight chance of showers after midnight. Waves calm to 2 feet. .SATURDAY...Southeast winds 5 to 15 knots. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 5 to 15 knots becoming south 10 to 20 knots after midnight. Waves calm to 2 feet. .SUNDAY...South winds 5 to 15 knots. Waves calm to 2 feet. .SUNDAY NIGHT...South winds 10 to 20 knots becoming southwest 15 to 25 knots after midnight. Waves building to 2 to 4 feet. .MONDAY...Southwest winds 10 to 20 knots increasing to 20 to 30 knots. Waves building to 4 to 7 feet occasionally to 9 feet. .TUESDAY...West winds 15 to 25 knots becoming northwest 10 to 20 knots. Waves subsiding to calm to 2 feet. $$ LSZ267-100800- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 401 PM EDT Thu Jul 9 2026...DENSE FOG ADVISORY IN EFFECT UNTIL 8 AM EDT FRIDAY... .LATE THIS AFTERNOON...Northwest winds 5 to 15 knots. Waves calm to 2 feet. .TONIGHT...Northwest winds 5 to 15 knots. Patchy fog through midnight, then areas of dense fog after midnight. Waves calm to 2 feet. .FRIDAY...North winds 5 to 15 knots backing northwest in the afternoon. Areas of dense fog through early afternoon. Waves calm to 2 feet. .FRIDAY NIGHT...North winds 5 to 15 knots veering south after midnight, then backing southeast late. Waves calm to 2 feet. .SATURDAY...Southeast winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 5 to 15 knots becoming south 10 to 20 knots after midnight. Waves calm to 2 feet. .SUNDAY...South winds 5 to 15 knots backing southeast by mid afternoon. Waves calm to 2 feet. .SUNDAY NIGHT...South winds 5 to 15 knots becoming southwest 10 to 20 knots after midnight. Waves building to 1 to 3 feet. .MONDAY...Southwest winds 5 to 15 knots increasing to 10 to 20 knots. Waves subsiding to calm to 2 feet, then building to 2 to 4 feet. .TUESDAY...West winds 10 to 20 knots becoming northwest 5 to 15 knots. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to calm to 2 feet. $$ LSZ261-100200- MAFOR 0921/ Superior West 11100 13800 11100 12200 11100. Waves 1 foot or less. Superior North Central 12600 11700 11700 19704 11100 11200 12300. Waves 1 foot or less. Superior South Central 11800 12600 11800 19804 11804 11100 19104 11200 11300. Waves 1 foot or less. Superior East 13700 11704 12804 11700 11600. Waves 1 foot or less. $$ WFO MQT Experimental modernized open lake forecast is available online at weather.gov/mqt/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes  418 FZUS61 KBUF 092002 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 402 PM EDT Thu Jul 9 2026 For waters beyond five nautical miles of shore on Lake Ontario Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum. .SYNOPSIS...A weak cold front will cross the Lake tonight through early Friday. Another 30.0 inch high will then build across the upper Great Lakes Friday and the lower Great Lakes over the weekend, expanding east into New England Monday, then drifting south into the Mid-Atlantic Tuesday. This will allow for a warm front to pass across the lake Tuesday. LOZ062-100300- Lake Ontario open waters from the Niagara River to Hamlin Beach- 402 PM EDT Thu Jul 9 2026 .TONIGHT...West winds 10 knots or less becoming northwest. Showers likely with a chance of thunderstorms early, then a chance of showers from late evening on. Waves 1 foot or less. .FRIDAY...North winds less than 10 knots. Waves 1 foot or less. .FRIDAY NIGHT...Light and variable winds becoming northeast 5 to 10 knots. Waves 1 foot or less. .SATURDAY...Northeast winds 10 knots or less becoming east. Waves 2 feet or less. .SATURDAY NIGHT...Northeast winds less than 10 knots. Waves 1 foot or less. .SUNDAY...Light and variable winds. Waves 1 foot or less. .MONDAY...Southwest winds 10 knots or less. Waves 2 feet or less. .TUESDAY...Southwest winds 10 to 15 knots becoming west 15 to 20 knots. Waves 1 to 3 feet building to 3 to 5 feet. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-100300- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 402 PM EDT Thu Jul 9 2026 .TONIGHT...Northwest winds 5 to 10 knots. A chance of showers and thunderstorms early, then a chance of showers late this evening. A chance of showers late. Waves 1 foot or less. .FRIDAY...Northwest winds less than 10 knots. A chance of showers early. Waves 1 foot or less. .FRIDAY NIGHT...Northwest winds 10 knots or less becoming northeast 10 to 15 knots. Waves 2 feet or less. .SATURDAY...Northeast winds 5 to 15 knots. Waves 2 feet or less. .SATURDAY NIGHT...North winds 10 knots or less becoming northeast. Waves 1 foot or less. .SUNDAY...Northeast winds 10 knots or less becoming south. Waves 1 foot or less. .MONDAY...South winds 5 to 10 knots becoming southwest. Waves 2 feet or less. .TUESDAY...Southwest winds 10 to 15 knots becoming west 15 to 20 knots. Waves 1 to 3 feet building to 3 to 5 feet. Winds and waves higher in and near thunderstorms. $$ LOZ061-100300- MAFOR 0921/ ONTARIO WEST 1/2 11706 11500 12600 13800 11100. A chance of thunderstorms this evening. Waves 1 foot or less. ONTARIO EAST 1/2 11700 13600 11700 11800 12700. A chance of showers and thunderstorms this evening. Waves 1 foot or less. $$  441 FZUS61 KBUF 092003 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 403 PM EDT Thu Jul 9 2026 SLZ022-024-100300- Saint Lawrence River from Cape Vincent to Saint Regis 403 PM EDT Thu Jul 9 2026 .TONIGHT...Light and variable winds. Showers with a chance of thunderstorms early, then a chance of showers and thunderstorms late this evening. .FRIDAY...Light and variable winds. Becoming mostly sunny. .FRIDAY NIGHT...North winds less than 10 knots. Mainly clear in the evening, then becoming partly cloudy. .SATURDAY...Northeast winds 10 knots or less becoming north. Sunny. .SATURDAY NIGHT...North winds less than 10 knots. Clear. .SUNDAY...Light and variable winds. Mainly clear. .MONDAY...Southwest winds 5 to 10 knots. Mainly clear, then becoming partly cloudy. .TUESDAY...Southwest winds 5 to 15 knots becoming west. A chance of showers Tuesday night. Winds and waves higher in and near thunderstorms. $$