318 FZUS63 KMQT 162001 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 400 PM EDT Thu Apr 16 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 ridging of around 29.8 inches persists over Lake Superior through tonight. Troughing averaging 29.5 inches moves across the lake Friday evening and Saturday morning. Ridging builds over Lake Superior the remainder of Saturday and throughout Sunday, reaching about 30.3 inches Monday morning. This gives way quickly to troughing Monday evening as a low swings southeast through Ontario toward James Bay, decreasing to around 29.6 by Monday evening. LSZ162-170800- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 400 PM EDT Thu Apr 16 2026 /300 PM CDT Thu Apr 16 2026/ .LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to 2 feet. .TONIGHT...Northeast winds 10 to 20 knots. Patchy fog. Waves building to 2 to 4 feet. .FRIDAY...East winds 10 to 20 knots backing northeast in the afternoon, then backing northwest late. Patchy fog through early afternoon. Rain showers likely and a chance of thunderstorms by mid afternoon. Waves subsiding to 1 to 3 feet. .FRIDAY NIGHT...West winds 15 to 25 knots increasing to 20 to 30 knots late. Rain showers likely and a slight chance of thunderstorms through midnight, then a slight chance of rain showers after midnight. Waves building to 3 to 5 feet occasionally to 7 feet. .SATURDAY...West gales to 35 knots diminishing to 20 to 30 knots by mid afternoon. A slight chance of snow showers. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .SATURDAY NIGHT...Northwest winds 20 to 30 knots diminishing to 15 to 25 knots after midnight. Waves subsiding to 2 to 4 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 east after midnight. Waves calm to 2 feet. .MONDAY...South winds 10 to 20 knots becoming southwest 15 to 25 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 north 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ263-170800- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 400 PM EDT Thu Apr 16 2026 .LATE THIS AFTERNOON...East winds 5 to 15 knots. Waves calm to 2 feet. .TONIGHT...East winds 5 to 15 knots veering southeast late. Patchy fog. Waves building to 2 to 4 feet. .FRIDAY...East winds 10 to 20 knots veering south late. Patchy fog through early afternoon. A chance of showers and thunderstorms by mid afternoon. Waves building to 3 to 6 feet occasionally to 8 feet. .FRIDAY NIGHT...West winds 20 to 30 knots. Rain showers and a chance of thunderstorms through midnight, then a slight chance of rain showers, snow showers and sleet after midnight. Waves subsiding to 3 to 5 feet occasionally to 7 feet, then building to 4 to 7 feet occasionally to 9 feet. .SATURDAY...West winds 20 to 30 knots increasing to gales to 35 knots by mid afternoon. A slight chance of snow showers. Waves building to 8 to 11 feet occasionally to 14 feet. .SATURDAY NIGHT...Northwest gales to 35 knots. Waves subsiding to 4 to 7 feet occasionally to 9 feet. .SUNDAY...Northwest winds 20 to 30 knots becoming west 15 to 25 knots by mid afternoon. Waves subsiding to 1 to 3 feet. .SUNDAY NIGHT...Northwest winds 10 to 20 knots becoming south 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .MONDAY...South winds 10 to 20 knots becoming southwest 20 to 30 knots. Waves building to 4 to 7 feet occasionally to 9 feet. .TUESDAY...West winds 15 to 25 knots becoming north 5 to 15 knots. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet. $$ LSZ264-170800- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 400 PM EDT Thu Apr 16 2026 .LATE THIS AFTERNOON...Southeast winds 5 to 15 knots. Patchy fog. Waves calm to 2 feet. .TONIGHT...Southeast winds 5 to 15 knots increasing to 10 to 20 knots after midnight. Patchy fog through midnight, then areas of dense fog after midnight. Waves building to 3 to 5 feet occasionally to 7 feet. .FRIDAY...Southeast winds 15 to 25 knots increasing to 20 to 30 knots in the afternoon. Areas of dense fog through early afternoon. A slight chance of showers and thunderstorms by mid afternoon. Waves building to 6 to 9 feet occasionally to 11 feet. .FRIDAY NIGHT...South winds 20 to 30 knots becoming west 15 to 25 knots after midnight, then increasing to 20 to 30 knots late. Rain showers and a chance of thunderstorms through midnight, then a chance of rain showers, possibly mixed with freezing rain, snow showers and sleet after midnight. Waves building to 8 to 11 feet occasionally to 14 feet, then subsiding to 4 to 7 feet occasionally to 9 feet. .SATURDAY...West gales to 35 knots. A slight chance of snow showers through early afternoon. Waves building to 8 to 11 feet occasionally to 14 feet. .SATURDAY NIGHT...Northwest gales to 35 knots. Waves subsiding to 5 to 8 feet occasionally to 10 feet. .SUNDAY...Northwest winds 20 to 30 knots diminishing to 15 to 25 knots by mid afternoon. Waves subsiding to 2 to 4 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 20 to 30 knots becoming north 5 to 15 knots. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet. $$ LSZ265-170800- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 400 PM EDT Thu Apr 16 2026 .LATE THIS AFTERNOON...East winds 10 to 20 knots. Patchy dense fog. Waves calm to 2 feet. .TONIGHT...Southeast winds 10 to 20 knots increasing to 15 to 25 knots late. Areas of dense fog. Waves building to 2 to 4 feet. .FRIDAY...Southeast winds 20 to 30 knots becoming south to 30 knots with a few gale force gusts to 35 knots possible late. A slight chance of rain showers by mid afternoon. Waves building to 6 to 9 feet occasionally to 11 feet. .FRIDAY NIGHT...South winds to 30 knots with a few gale force gusts to 35 knots possible becoming west 20 to 30 knots after midnight, then increasing to 30 knots with a few gale force gusts to 35 knots possible late. Rain showers and a chance of thunderstorms through midnight, then a chance of rain showers, possibly mixed with snow and sleet after midnight. Waves building to 7 to 10 feet occasionally to 13 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .SATURDAY...West gales to 40 knots. A slight chance of rain showers through early afternoon. A slight chance of snow showers and sleet. Waves building to 7 to 10 feet occasionally to 13 feet. .SATURDAY NIGHT...Northwest gales to 40 knots. Waves subsiding to 6 to 9 feet occasionally to 11 feet. .SUNDAY...Northwest gales to 35 knots diminishing to 20 to 30 knots by mid afternoon. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .SUNDAY NIGHT...Northwest winds 10 to 20 knots. Waves subsiding to calm to 2 feet. .MONDAY...Southeast winds 10 to 20 knots becoming south gales to 35 knots. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .TUESDAY...Northwest winds 20 to 30 knots diminishing to 10 to 20 knots. Waves subsiding to calm to 2 feet, then building to 2 to 4 feet. $$ LSZ266-170800- 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- 400 PM EDT Thu Apr 16 2026 .LATE THIS AFTERNOON...East winds 5 to 15 knots. Patchy dense fog. Waves calm to 2 feet. .TONIGHT...Southeast winds 5 to 15 knots increasing to 10 to 20 knots after midnight. Areas of dense fog. Waves building to 3 to 5 feet occasionally to 7 feet. .FRIDAY...Southeast winds 15 to 25 knots increasing to 20 to 30 knots in the afternoon, then becoming south to 30 knots with a few gale force gusts to 35 knots possible late. Areas of dense fog through early afternoon. Waves building to 7 to 10 feet occasionally to 13 feet. .FRIDAY NIGHT...South winds to 30 knots with a few gale force gusts to 35 knots possible veering west late. A slight chance of thunderstorms through midnight. Rain showers. A slight chance of sleet 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...West gales to 40 knots. A slight chance of rain showers through early afternoon. A slight chance of freezing rain, snow showers and sleet. Waves building to 10 to 14 feet occasionally to 18 feet. .SATURDAY NIGHT...Northwest gales to 40 knots. Waves 10 to 14 feet occasionally to 18 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 10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet. .MONDAY...South winds 15 to 25 knots increasing to gales to 40 knots. Waves subsiding to calm to 2 feet, then building to 7 to 10 feet occasionally to 13 feet. .TUESDAY...West winds 20 to 30 knots becoming northwest 10 to 20 knots. Waves subsiding to 2 to 4 feet, then building to 3 to 5 feet occasionally to 7 feet. $$ LSZ267-170800- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 400 PM EDT Thu Apr 16 2026 .LATE THIS AFTERNOON...Northwest winds 5 to 15 knots. Areas of dense fog. Waves calm to 2 feet. .TONIGHT...East winds 5 to 15 knots veering southeast after midnight. Areas of dense fog through midnight, then widespread dense fog after midnight. Waves calm to 2 feet. .FRIDAY...Southeast winds 10 to 20 knots increasing to 20 to 30 knots. Areas of dense fog through early afternoon. Waves building to 4 to 7 feet occasionally to 9 feet. .FRIDAY NIGHT...Southeast winds to 30 knots with a few gale force gusts to 35 knots possible veering south after midnight, then veering west late. Rain showers and a slight chance of thunderstorms. Waves building to 4 to 8 feet occasionally to 10 feet. .SATURDAY...West gales to 40 knots. A chance of rain showers, possibly mixed with snow. A slight chance of sleet by mid afternoon. Waves building to 10 to 14 feet occasionally to 18 feet. .SATURDAY NIGHT...West gales to 40 knots veering northwest after midnight. Waves subsiding to 10 to 14 feet occasionally to 18 feet. .SUNDAY...Northwest gales to 40 knots. Waves subsiding to 7 to 10 feet occasionally to 13 feet. .SUNDAY NIGHT...Northwest winds 15 to 25 knots becoming north 10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet. .MONDAY...South winds 10 to 20 knots increasing to gales to 35 knots. Waves subsiding to calm to 2 feet, then building to 6 to 9 feet occasionally to 11 feet. .TUESDAY...West winds 20 to 30 knots becoming northwest 10 to 20 knots. Waves subsiding to 2 to 4 feet, then building to 3 to 5 feet occasionally to 7 feet. $$ LSZ261-170200- MAFOR 1621/ Superior West 12210 11120 13220 11210 11110. A chance of rain showers Friday afternoon. Waves 1 to 3 feet building to 2 to 4 feet tonight. Waves 2 to 4 feet Friday. Superior North Central 11300 11310 13324 11334 11330 11340. Waves 1 to 3 feet building to 2 to 4 feet tonight. Waves 3 to 6 feet building to 4 to 7 feet Friday. Superior South Central 11210 19214 11310 13324 11334 12340. Waves 1 to 3 feet tonight. Waves 2 to 4 feet building to 4 to 7 feet Friday. Superior East 11800 19804 11204 11304 11314 12324 12330. Waves 2 feet or less tonight. Waves 1 to 3 feet building to 3 to 6 feet Friday. $$ 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  118 FZUS61 KBUF 162010 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 410 PM EDT Thu Apr 16 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 29.7 inch low over southern Quebec will move to the Saint Lawrence Valley this evening, then to the Canadian Maritimes by Friday morning...with a 30.0 inch high then building across the Lower Great Lakes Friday, and New England Friday night. A 29.4 inch low near Lake Superior Friday 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. LOZ062-170300- Lake Ontario open waters from the Niagara River to Hamlin Beach- 410 PM EDT Thu Apr 16 2026 .TONIGHT...West winds 5 to 15 knots becoming northwest. Showers likely with a chance of thunderstorms early, then a chance of showers. Some thunderstorms may produce gusty winds early. Waves 2 to 4 feet subsiding to 1 to 3 feet. .FRIDAY...Northwest winds 10 knots or less becoming south. Waves 1 foot or less. .FRIDAY NIGHT...Southeast winds 10 knots or less becoming east. Waves 1 foot or less. .SATURDAY...Southeast winds 5 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...Southwest winds 15 to 20 knots becoming west. Rain showers. Waves 2 to 4 feet building to 3 to 5 feet. .SUNDAY...West winds 15 to 25 knots becoming northwest. A chance of rain showers during the day. Waves 3 to 6 feet. .MONDAY...Northwest winds 15 to 20 knots becoming southwest 10 to 15 knots. Waves 3 to 6 feet subsiding to 1 to 2 feet. .TUESDAY...South winds 15 to 20 knots becoming west. Waves 2 to 4 feet building to 3 to 5 feet. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-170300- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 410 PM EDT Thu Apr 16 2026 .TONIGHT...Southwest winds 5 to 15 knots becoming northwest. Showers with a chance of thunderstorms early, then a chance of showers from late evening on. Some thunderstorms may produce gusty winds early. Waves 1 to 3 feet. .FRIDAY...North winds 10 knots or less becoming west. A chance of showers early. Waves 2 feet or less. .FRIDAY NIGHT...West winds 10 knots or less becoming southeast. Waves 1 foot or less. .SATURDAY...Southeast winds 10 to 15 knots becoming south 15 to 20 knots. Showers likely in the afternoon. Waves 1 to 3 feet building to 2 to 4 feet. .SATURDAY NIGHT...South winds 15 to 20 knots becoming west. Rain showers. Waves 2 to 4 feet building to 3 to 6 feet. .SUNDAY...West winds 15 to 25 knots becoming northwest. Rain showers likely with a chance of snow showers during the day, then a chance of rain and snow showers Sunday night. Waves 3 to 6 feet building to 5 to 9 feet. Waves occasionally around 11 feet. .MONDAY...Northwest winds 15 to 25 knots becoming west. Waves 5 to 8 feet subsiding to 3 to 6 feet. Waves occasionally around 10 feet. .TUESDAY...South winds 15 to 20 knots becoming west. A chance of rain showers Tuesday night. Waves 2 to 4 feet building to 3 to 5 feet. Winds and waves higher in and near thunderstorms. $$ LOZ061-170300- MAFOR 1621/ ONTARIO WEST 1/2 11516 11600 13700 11800 11700 11500. A chance of thunderstorms this evening. Waves 2 to 4 feet subsiding to 1 to 3 feet tonight. Waves 1 foot or less Friday. ONTARIO EAST 1/2 11516 12600 12700 11800 12700. A chance of thunderstorms this evening. Waves 1 to 3 feet tonight. Waves 2 feet or less Friday. $$  311 FZUS61 KBUF 162012 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 412 PM EDT Thu Apr 16 2026 SLZ022-024-170300- Saint Lawrence River from Cape Vincent to Saint Regis 412 PM EDT Thu Apr 16 2026 .TONIGHT...Southwest winds 10 knots or less becoming north. Showers with a chance of thunderstorms early, then showers likely late this evening. A chance of showers after midnight. .FRIDAY...North winds less than 10 knots becoming northeast. Mostly cloudy through early afternoon, then becoming partly sunny. .FRIDAY NIGHT...Northeast winds less than 10 knots. Mainly clear in the evening, 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 southwest. 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. Partly cloudy, then becoming mainly clear. .TUESDAY...South winds 5 to 15 knots becoming southwest. A chance of rain showers. Winds and waves higher in and near thunderstorms. $$