Great Lakes Forecast
Issued by NWS
Issued by NWS
313 FZUS63 KMQT 200201 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 1000 PM EDT Thu Mar 19 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 around 30.1 inches over Lake Superior gives way to a clipper low moving across the lake tonight into early Friday at around 29.7 inches. While another low moves through northern Ontario toward the north shores of Lake Superior Friday night, another low stretches into the Northern Plains around the same time. Together, these lows are expected to bring about troughing of around around 29.8 inch over Lake Superior on Saturday into Sunday. Behind the troughing, 30.4 inch ridging builds into the Great Lakes and Northern Plains by Monday. A 29.9 inch clipper low tracking across northern Ontario on Tuesday briefly extends a 30.0 inch trough over the lake. A 30.5 inch high quickly follows behind it for Wednesday. LSZ162-200800- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 1000 PM EDT Thu Mar 19 2026 /900 PM CDT Thu Mar 19 2026/ .REST OF TONIGHT...South winds 10 to 20 knots veering west late. A chance of freezing rain and rain showers by midnight. Waves calm to 2 feet. .FRIDAY...West winds 5 to 15 knots. Waves calm to 2 feet. .FRIDAY NIGHT...West winds 5 to 15 knots veering northeast late. Waves calm to 2 feet. .SATURDAY...East winds 5 to 15 knots becoming northeast 10 to 20 knots by mid afternoon. A chance of rain and snow showers. Waves building to 1 to 3 feet. .SATURDAY NIGHT...Northeast winds 15 to 25 knots. A chance of snow showers, possibly mixed with rain. Waves building to 4 to 7 feet occasionally to 9 feet. .SUNDAY...Northeast winds 15 to 25 knots diminishing to 10 to 20 knots by mid afternoon. A chance of snow showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .SUNDAY NIGHT...Northeast winds 10 to 20 knots becoming northwest 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .MONDAY...Southwest winds 5 to 15 knots increasing to 20 to 30 knots. Waves building to 3 to 5 feet occasionally to 7 feet. .TUESDAY...West winds 15 to 25 knots becoming northeast 10 to 20 knots. Waves subsiding to calm to 2 feet, then building to 3 to 5 feet occasionally to 7 feet. $$ LSZ263-200800- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 1000 PM EDT Thu Mar 19 2026 .REST OF TONIGHT...South winds 10 to 20 knots veering southwest after midnight, then becoming west 5 to 15 knots late. Freezing rain and snow showers likely by midnight. A chance of rain showers. Waves 2 to 4 feet subsiding to 1 to 3 feet. .FRIDAY...Northwest winds 5 to 15 knots backing west in the afternoon. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...West winds 5 to 15 knots veering northeast late. Waves calm to 2 feet. .SATURDAY...East winds 5 to 15 knots increasing to 15 to 25 knots by mid afternoon. A chance of snow showers, possibly mixed with rain. Waves building to 1 to 3 feet. .SATURDAY NIGHT...Northeast winds 15 to 25 knots. A chance of rain showers through midnight. A chance of snow showers. Waves building to 5 to 8 feet occasionally to 10 feet. .SUNDAY...Northeast winds 20 to 30 knots diminishing to 15 to 25 knots by mid afternoon. Freezing spray through early afternoon. A chance of snow showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .SUNDAY NIGHT...Northeast winds 5 to 15 knots backing north after midnight. Waves subsiding to 2 to 4 feet. .MONDAY...Northwest winds 10 to 20 knots becoming southwest 20 to 30 knots. Waves subsiding to calm to 2 feet, then building to 5 to 8 feet occasionally to 10 feet. .TUESDAY...West winds 20 to 30 knots becoming northeast 15 to 25 knots. Waves subsiding to 1 to 3 feet, then building to 4 to 7 feet occasionally to 9 feet. $$ LSZ264-200800- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 1000 PM EDT Thu Mar 19 2026 .REST OF TONIGHT...Southeast winds 15 to 25 knots veering south after midnight, then becoming west 10 to 20 knots late. Snow showers by midnight. A chance of rain showers. A chance of snow showers after midnight. Waves 2 to 4 feet building to 3 to 5 feet occasionally to 7 feet. .FRIDAY...North winds 5 to 15 knots backing west late. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...West winds 5 to 15 knots veering north late. Waves calm to 2 feet. .SATURDAY...East winds 5 to 15 knots increasing to 10 to 20 knots by mid afternoon. A chance of rain showers through early afternoon. A chance of snow showers. Waves building to 1 to 3 feet. .SATURDAY NIGHT...Northeast winds 15 to 25 knots increasing to 20 to 30 knots after midnight. A chance of snow showers. Freezing spray after midnight. Waves building to 5 to 8 feet occasionally to 10 feet. .SUNDAY...Northeast winds 20 to 30 knots diminishing to 15 to 25 knots by mid afternoon. Freezing spray. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .SUNDAY NIGHT...Northeast winds 5 to 15 knots backing north after midnight. Waves subsiding to 2 to 4 feet. .MONDAY...Northwest winds 5 to 15 knots becoming southwest gales to 35 knots. Waves subsiding to calm to 2 feet, then building to 6 to 9 feet occasionally to 11 feet. .TUESDAY...West gales to 35 knots becoming northeast 20 to 30 knots. Freezing spray. Waves subsiding to 3 to 5 feet occasionally to 7 feet, then building to 5 to 8 feet occasionally to 10 feet. $$ LSZ265-200800- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 1000 PM EDT Thu Mar 19 2026 .REST OF TONIGHT...Southeast winds 15 to 25 knots increasing to 20 to 30 knots after midnight, then becoming west 15 to 25 knots late. Rain showers likely, possibly mixed with freezing rain by midnight. Snow showers. A chance of rain showers after midnight. Waves 2 to 4 feet building to 3 to 5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet. .FRIDAY...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots in the afternoon, then backing west late. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...West winds 10 to 20 knots. Waves calm to 2 feet. .SATURDAY...East winds 10 to 20 knots increasing to 15 to 25 knots by mid afternoon. A slight chance of rain showers through early afternoon. A chance of snow showers. Waves building to 1 to 3 feet. .SATURDAY NIGHT...Northeast winds 20 to 30 knots. A chance of snow showers. Waves building to 5 to 8 feet occasionally to 10 feet. .SUNDAY...Northeast gales to 35 knots diminishing to 20 to 30 knots by mid afternoon. Freezing spray through early afternoon. A chance of snow showers. Waves building to 6 to 9 feet occasionally to 11 feet, then subsiding to 4 to 7 feet occasionally to 9 feet. .SUNDAY NIGHT...North winds 15 to 25 knots. Waves subsiding to 3 to 6 feet occasionally to 8 feet. .MONDAY...Northwest winds 10 to 20 knots becoming southwest gales to 35 knots. Waves subsiding to calm to 2 feet, then building to 4 to 7 feet occasionally to 9 feet. .TUESDAY...West gales to 35 knots becoming northwest 20 to 30 knots. Freezing spray. Waves subsiding to 2 to 4 feet, then building to 6 to 9 feet occasionally to 11 feet. $$ LSZ266-200800- 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 PM EDT Thu Mar 19 2026 .REST OF TONIGHT...South winds 20 to 30 knots backing southeast after midnight, then becoming south 15 to 25 knots late. A slight chance of freezing rain by midnight. Snow showers. A slight chance of rain showers after midnight. Waves 2 to 4 feet building to 3 to 6 feet occasionally to 8 feet, then subsiding to 3 to 5 feet occasionally to 7 feet. .FRIDAY...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots in the afternoon. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...West winds 10 to 20 knots veering northwest late. Waves building to 1 to 3 feet. .SATURDAY...Southeast winds 10 to 20 knots becoming east 15 to 25 knots by mid afternoon. A chance of rain showers through early afternoon. A chance of snow showers. Waves 1 to 3 feet. .SATURDAY NIGHT...East winds 15 to 25 knots becoming northeast 20 to 30 knots after midnight. A chance of snow showers. Waves building to 5 to 8 feet occasionally to 10 feet. .SUNDAY...Northeast gales to 35 knots diminishing to 20 to 30 knots by mid afternoon. Freezing spray through early afternoon. A chance of snow showers. Waves building to 6 to 9 feet occasionally to 11 feet, then subsiding to 4 to 7 feet occasionally to 9 feet. .SUNDAY NIGHT...Northeast winds 15 to 25 knots backing north after midnight. Waves subsiding to 3 to 6 feet occasionally to 8 feet. .MONDAY...Northwest winds 10 to 20 knots becoming south gales to 40 knots. Waves subsiding to 1 to 3 feet, then building to 9 to 12 feet occasionally to 15 feet. .TUESDAY...West gales to 40 knots becoming north 20 to 30 knots. Freezing spray. Waves subsiding to 5 to 8 feet occasionally to 10 feet, then building to 6 to 9 feet occasionally to 11 feet. $$ LSZ267-200800- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 1000 PM EDT Thu Mar 19 2026 .REST OF TONIGHT...Southeast winds 10 to 20 knots becoming south 15 to 25 knots late. Snow showers. A slight chance of rain showers after midnight. Waves calm to 2 feet building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY...Northwest winds 10 to 20 knots. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...West winds 10 to 20 knots. Waves calm to 2 feet. .SATURDAY...Southeast winds 10 to 20 knots backing east by mid afternoon. A chance of snow showers. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. .SATURDAY NIGHT...East winds 15 to 25 knots becoming northeast 20 to 30 knots after midnight. A chance of snow showers. Waves building to 3 to 6 feet occasionally to 8 feet. .SUNDAY...Northeast winds 20 to 30 knots diminishing to 15 to 25 knots by mid afternoon. Freezing spray through early afternoon. A chance of snow showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .SUNDAY NIGHT...Northeast winds 15 to 25 knots becoming north 10 to 20 knots after midnight. Waves subsiding to 2 to 4 feet, then building to 3 to 5 feet occasionally to 7 feet. .MONDAY...North winds 10 to 20 knots becoming south gales to 35 knots. Freezing spray. A chance of snow showers. Waves subsiding to calm to 2 feet, then building to 7 to 10 feet occasionally to 13 feet. .TUESDAY...West gales to 35 knots becoming northwest 15 to 25 knots. A chance of snow showers. Freezing spray. Waves building to 9 to 12 feet occasionally to 15 feet, then subsiding to 4 to 7 feet occasionally to 9 feet. $$ LSZ261-200800- MAFOR 2003/ Superior West 11510 12610 11700 14600. Waves 2 feet or less. Superior North Central 11337 11437 11620 11820 12710 11600 11610. A chance of light freezing rain overnight. Waves 2 to 4 feet building to 3 to 5 feet overnight. Waves 3 to 5 feet subsiding to 2 to 4 feet Friday. Waves 1 to 2 feet Friday evening. Superior South Central 11337 11437 11520 12720 12710 11610. A chance of rain showers overnight. Waves 2 to 4 feet building to 3 to 5 feet overnight. Waves 2 to 4 feet subsiding to 1 to 3 feet Friday. Waves 2 feet or less Friday evening. Superior East 12337 11420 11720 11810 12710 11610. A chance of light freezing rain overnight. Waves 1 to 2 feet building to 3 to 5 feet overnight. Waves 2 to 4 feet subsiding to 1 to 3 feet Friday. Waves around 2 feet Friday evening. $$ 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