Great Lakes Forecast
Issued by NWS
Issued by NWS
924 FZUS63 KMQT 230201 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 1000 PM EDT Wed Jul 22 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 30.1 inch high pressure will continue to move through the midwest through early Friday morning. While ridging of around 30.0 inches looks to remain over Lake Superior on Thursday, a weak 29.9 to 30.0 inch low could move over the northwestern half of the lake by Thursday night into Friday morning. As a low around 29.3 inches lifts from far northern Ontario into Hudson Bay Friday night into Saturday morning, expect troughing of around 29.8 inches to move into Lake Superior in response by Saturday morning. Troughing of at least 29.8 inches looks to remain over the lake for the rest of the day. While weak ridging of 29.8 to 29.9 inches develops over Lake Superior Sunday morning, a 29.6 inch low moving in from the west moves over the Upper Great Lakes by Monday morning. LSZ162-230800- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 1001 PM EDT Wed Jul 22 2026 /901 PM CDT Wed Jul 22 2026/ .REST OF TONIGHT...Southwest winds 10 to 20 knots veering west after midnight, then backing southwest late. Waves 1 to 3 feet subsiding to calm to 2 feet. .THURSDAY...Southwest winds 10 to 20 knots increasing to 15 to 25 knots in the afternoon. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to 15 to 25 knots late. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet. .FRIDAY...Southwest winds 15 to 25 knots. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet. .FRIDAY NIGHT...Southwest winds 20 to 30 knots. A slight chance of showers through midnight. A chance of thunderstorms. Showers after midnight. Waves building to 3 to 6 feet occasionally to 8 feet. .SATURDAY...Southwest winds 15 to 25 knots diminishing to 10 to 20 knots by mid afternoon. Waves subsiding to calm to 2 feet. .SATURDAY NIGHT...North winds 5 to 15 knots veering northeast after midnight. Waves calm to 2 feet. .SUNDAY...Northeast winds 5 to 15 knots. A chance of showers. Waves calm to 2 feet. .MONDAY...North winds 5 to 15 knots veering northeast. Waves calm to 2 feet. $$ LSZ263-230800- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 1001 PM EDT Wed Jul 22 2026 .REST OF TONIGHT...Southwest winds 10 to 20 knots veering west after midnight, then increasing to 15 to 25 knots late. Waves 2 to 4 feet subsiding to 1 to 3 feet, then building to 2 to 4 feet. .THURSDAY...Southwest winds 15 to 25 knots. A slight chance of showers and thunderstorms by mid afternoon. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet. .THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to 15 to 25 knots after midnight. A slight chance of showers through midnight. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet. .FRIDAY...Southwest winds 20 to 30 knots. Waves building to 3 to 6 feet occasionally to 8 feet. .FRIDAY NIGHT...Southwest winds 20 to 30 knots. A slight chance of showers through midnight, then showers and a slight chance of thunderstorms after midnight. Waves subsiding to 2 to 4 feet, then building to 4 to 7 feet occasionally to 9 feet. .SATURDAY...Southwest winds 20 to 30 knots becoming west 10 to 20 knots by mid afternoon. A chance of showers through early afternoon. Waves subsiding to 1 to 3 feet. .SATURDAY NIGHT...Northeast winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .SUNDAY...East winds 5 to 15 knots backing northeast. A chance of showers. Waves calm to 2 feet. .MONDAY...Northeast winds 5 to 15 knots. Waves calm to 2 feet. $$ LSZ264-230800- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 1001 PM EDT Wed Jul 22 2026 .REST OF TONIGHT...West winds 10 to 20 knots increasing to 15 to 25 knots late. Waves 2 to 4 feet. .THURSDAY...Southwest winds 15 to 25 knots. A slight chance of showers by mid afternoon. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet. .THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to 15 to 25 knots late. A chance of showers and a slight chance of thunderstorms through midnight. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet. .FRIDAY...Southwest winds 15 to 25 knots. Waves building to 3 to 6 feet occasionally to 8 feet, then subsiding to 2 to 4 feet. .FRIDAY NIGHT...South winds 20 to 30 knots veering southwest after midnight. A slight chance of showers through midnight, then showers and a slight chance of thunderstorms after midnight. Waves building to 4 to 7 feet occasionally to 9 feet. .SATURDAY...Southwest winds 20 to 30 knots becoming west 10 to 20 knots by mid afternoon. A chance of showers through early afternoon. Waves subsiding to 2 to 4 feet. .SATURDAY NIGHT...North winds 5 to 15 knots becoming northeast less than 10 knots after midnight. Waves subsiding to calm to 2 feet. .SUNDAY...Southeast winds 5 to 15 knots. A chance of showers. Waves calm to 2 feet. .MONDAY...Northwest winds 5 to 15 knots veering north. Waves calm to 2 feet. $$ LSZ265-230800- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 1001 PM EDT Wed Jul 22 2026 .REST OF TONIGHT...West winds 15 to 25 knots increasing to 20 to 30 knots late. Waves calm to 2 feet building to 1 to 3 feet. .THURSDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots in the afternoon. Waves subsiding to calm to 2 feet. .THURSDAY NIGHT...Southwest winds 10 to 20 knots increasing to 15 to 25 knots after midnight. Waves building to 1 to 3 feet. .FRIDAY...Southwest winds 15 to 25 knots becoming south 10 to 20 knots by mid afternoon. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...South winds 15 to 25 knots becoming southwest gales to 35 knots after midnight. A chance of showers and a slight chance of thunderstorms after midnight. Waves building to 3 to 5 feet occasionally to 7 feet. .SATURDAY...Southwest winds 20 to 30 knots becoming west 10 to 20 knots by mid afternoon. Showers likely through early afternoon. Waves subsiding to calm to 2 feet. .SATURDAY NIGHT...North winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves calm to 2 feet. .SUNDAY...East winds 5 to 15 knots becoming south 10 to 20 knots. A chance of showers and thunderstorms. Waves calm to 2 feet. .MONDAY...North winds 10 to 20 knots. Waves calm to 2 feet. $$ LSZ266-230800- 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- 1001 PM EDT Wed Jul 22 2026 .REST OF TONIGHT...West winds 10 to 20 knots increasing to 15 to 25 knots late. Waves 2 to 4 feet. .THURSDAY...West winds 15 to 25 knots becoming southwest 10 to 20 knots late. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet. .THURSDAY NIGHT...South winds 10 to 20 knots veering southwest after midnight, then increasing to 15 to 25 knots late. A slight chance of showers through midnight. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet. .FRIDAY...Southwest winds 10 to 20 knots becoming south 15 to 25 knots by mid afternoon. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet. .FRIDAY NIGHT...South winds 20 to 30 knots increasing to gales to 35 knots after midnight. A chance of showers and a slight chance of thunderstorms after midnight. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .SATURDAY...Southwest winds 15 to 25 knots becoming west 10 to 20 knots by mid afternoon. Showers through early afternoon. A chance of thunderstorms. A chance of showers by mid afternoon. Waves subsiding to 2 to 4 feet. .SATURDAY NIGHT...North winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .SUNDAY...East winds 5 to 15 knots becoming south 10 to 20 knots. A chance of showers. Waves calm to 2 feet. .MONDAY...Northwest winds 10 to 20 knots veering north. Waves calm to 2 feet. $$ LSZ267-230800- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 1001 PM EDT Wed Jul 22 2026 .REST OF TONIGHT...West winds 10 to 20 knots diminishing to 5 to 15 knots after midnight, then backing southwest late. Waves 2 to 4 feet subsiding to 1 to 3 feet. .THURSDAY...Southwest winds 10 to 20 knots veering west in the afternoon, then becoming southwest 5 to 15 knots late. Waves 1 to 3 feet. .THURSDAY NIGHT...South winds 5 to 15 knots becoming southwest 10 to 20 knots after midnight. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet. .FRIDAY...Southwest winds 5 to 15 knots backing south by mid afternoon. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...South winds 15 to 25 knots increasing to 20 to 30 knots after midnight. A slight chance of showers after midnight. Waves building to 3 to 6 feet occasionally to 8 feet. .SATURDAY...Southwest winds 15 to 25 knots diminishing to 5 to 15 knots by mid afternoon. Showers and a chance of thunderstorms. Waves subsiding to calm to 2 feet. .SATURDAY NIGHT...Northwest winds 5 to 15 knots. Waves calm to 2 feet. .SUNDAY...Northwest winds 5 to 15 knots becoming south 10 to 20 knots. A chance of showers. Waves calm to 2 feet. .MONDAY...Northwest winds 10 to 20 knots. Waves calm to 2 feet. $$ LSZ261-230800- MAFOR 2303/ Superior West 13520 14530 11520. Waves 2 feet or less overnight. Waves 1 to 3 feet building to 2 to 4 feet Thursday. Waves 1 to 3 feet Thursday evening. Superior North Central 12620 11520 14530 11520. Waves 2 to 4 feet overnight. Waves 2 to 4 feet building to 3 to 5 feet Thursday. Waves 3 to 5 feet subsiding to 2 to 4 feet Thursday evening. Superior South Central 11620 14630 11620 11510 11410. Waves 1 to 3 feet. Superior East 11620 13520 14510. Waves 2 to 4 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