FZUS63 KMQT 180802 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 401 AM EDT Mon May 18 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... Low pressure will weaken over the lake today with another low pressure following it, reaching Lake Superior by Tuesday morning at 29.6 inches. Afterwards, a 30.2 inch high over the Northern Plains builds to 30.4 inches Tuesday night into Wednesday as it traverses eastwards into the Upper Great Lakes. The high pressure shifts east on Thursday while leaving lingering ridging of at least 30.1 inches over Lake Superior into Friday. LSZ162-182000- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 401 AM EDT Mon May 18 2026 /301 AM CDT Mon May 18 2026/ .EARLY THIS MORNING...Northeast winds 10 to 20 knots. Patchy fog. Rain showers likely and a slight chance of thunderstorms. Waves 3 to 6 feet occasionally to 8 feet. .TODAY...Northeast winds 5 to 15 knots. Patchy fog. A slight chance of rain showers. Waves subsiding to 1 to 3 feet. .TONIGHT...Northeast winds 15 to 25 knots. Patchy fog. A chance of rain showers through midnight. A slight chance of thunderstorms. Rain showers after midnight. Waves building to 4 to 7 feet occasionally to 9 feet. .TUESDAY...North winds 10 to 20 knots backing west in the afternoon. A chance of rain showers through early afternoon. Waves subsiding to 1 to 3 feet. .TUESDAY NIGHT...Northwest winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .WEDNESDAY...Southwest winds 5 to 15 knots backing south by mid afternoon. Waves calm to 2 feet. .WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south after midnight. Waves calm to 2 feet. .THURSDAY...East winds 5 to 15 knots. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. .FRIDAY...East winds 5 to 15 knots backing northeast. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. $$ LSZ263-182000- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 401 AM EDT Mon May 18 2026 .EARLY THIS MORNING...East winds 10 to 20 knots. Patchy fog. Rain showers and a slight chance of thunderstorms. Waves 3 to 5 feet occasionally to 7 feet. .TODAY...North winds 10 to 20 knots diminishing to 5 to 15 knots in the afternoon, then becoming northeast 10 to 20 knots late. Patchy fog. A slight chance of rain showers. Waves subsiding to 1 to 3 feet. .TONIGHT...Northeast winds 15 to 25 knots. Patchy fog. A chance of rain showers through midnight. A slight chance of thunderstorms. Rain showers after midnight. Waves building to 5 to 8 feet occasionally to 10 feet. .TUESDAY...North winds 15 to 25 knots becoming west 10 to 20 knots in the afternoon. A chance of rain showers through early afternoon. Waves subsiding to 2 to 4 feet. .TUESDAY NIGHT...Northwest winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .WEDNESDAY...Northwest winds 5 to 15 knots backing southwest by mid afternoon. Waves building to 1 to 3 feet. .WEDNESDAY NIGHT...South winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .THURSDAY...South winds 5 to 15 knots increasing to 10 to 20 knots. Waves building to 1 to 3 feet. .FRIDAY...East winds 5 to 15 knots. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet. $$ LSZ264-182000- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 401 AM EDT Mon May 18 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 5 PM EDT THIS AFTERNOON... .EARLY THIS MORNING...East winds 15 to 25 knots. Patchy dense fog. Rain showers and a chance of thunderstorms. Waves 3 to 6 feet occasionally to 8 feet. .TODAY...East winds 5 to 15 knots backing north in the afternoon, then increasing to 10 to 20 knots late. Patchy dense fog. A chance of rain showers. Waves subsiding to 2 to 4 feet. .TONIGHT...Northeast winds 15 to 25 knots. Patchy fog. A chance of rain showers through midnight. A slight chance of thunderstorms. Rain showers after midnight. Waves building to 4 to 7 feet occasionally to 9 feet. .TUESDAY...North winds 15 to 25 knots backing northwest in the afternoon. Patchy fog through early afternoon. Rain showers likely through early afternoon. Waves building to 5 to 8 feet occasionally to 10 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .TUESDAY NIGHT...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots after midnight. Waves subsiding to 1 to 3 feet. .WEDNESDAY...Northwest winds 10 to 20 knots becoming southwest 5 to 15 knots by mid afternoon. Waves subsiding to calm to 2 feet. .WEDNESDAY NIGHT...Southwest winds 5 to 15 knots backing south after midnight. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots increasing to 10 to 20 knots. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY...Southeast winds 5 to 15 knots. Waves 1 to 3 feet. $$ LSZ265-182000- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 401 AM EDT Mon May 18 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 5 PM EDT THIS AFTERNOON... .EARLY THIS MORNING...Southeast winds 10 to 20 knots. Patchy dense fog. Rain showers and a chance of thunderstorms. Waves 3 to 6 feet occasionally to 8 feet. .TODAY...Southeast winds 10 to 20 knots veering west in the afternoon, then veering north late. Patchy dense fog. A chance of showers. Waves subsiding to calm to 2 feet. .TONIGHT...North winds 10 to 20 knots veering east late. Areas of dense fog through midnight. Patchy fog after midnight. A chance of rain showers through midnight. A slight chance of thunderstorms. Rain showers after midnight. Waves building to 2 to 4 feet. .TUESDAY...Northwest winds 15 to 25 knots increasing to 20 to 30 knots in the afternoon. Patchy fog through early afternoon. Rain showers likely and a slight chance of thunderstorms through early afternoon. Waves building to 4 to 7 feet occasionally to 9 feet. .TUESDAY NIGHT...Northwest winds 15 to 25 knots. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .WEDNESDAY...Northwest winds 10 to 20 knots becoming south 5 to 15 knots by mid afternoon. Waves subsiding to calm to 2 feet. .WEDNESDAY NIGHT...South winds 5 to 15 knots increasing to 10 to 20 knots after midnight. Waves calm to 2 feet. .THURSDAY...Southeast winds 10 to 20 knots veering south. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY...Southeast winds 10 to 20 knots. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. $$ LSZ266-182000- 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 AM EDT Mon May 18 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 5 PM EDT THIS AFTERNOON... .EARLY THIS MORNING...Southeast winds 15 to 25 knots. Areas of dense fog. Rain showers and a chance of thunderstorms. Waves 3 to 6 feet occasionally to 8 feet. .TODAY...South winds 10 to 20 knots veering southwest in the afternoon, then veering north late. Areas of dense fog. A slight chance of thunderstorms through early afternoon. A chance of showers. Waves subsiding to 2 to 4 feet. .TONIGHT...Northeast winds 15 to 25 knots veering east after midnight. Areas of dense fog. A chance of rain showers through midnight. A chance of thunderstorms. Rainshowers likely after midnight. Waves building to 3 to 6 feet occasionally to 8 feet. .TUESDAY...South winds 15 to 25 knots becoming northwest 20 to 30 knots in the afternoon, then increasing to 30 knots with a few gale force gusts to 35 knots possible late. Areas of dense fog through early afternoon. A slight chance of thunderstorms through early afternoon. A chance of rain showers. Waves building to 7 to 10 feet occasionally to 13 feet. .TUESDAY NIGHT...Northwest winds 20 to 30 knots. Waves subsiding to 4 to 7 feet occasionally to 9 feet. .WEDNESDAY...Northwest winds 15 to 25 knots becoming west 5 to 15 knots by mid afternoon. Waves subsiding to 1 to 3 feet. .WEDNESDAY NIGHT...Southwest winds 5 to 15 knots backing south after midnight. Waves subsiding to calm to 2 feet. .THURSDAY...South winds 10 to 20 knots. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY...Southeast winds 15 to 25 knots diminishing to 10 to 20 knots. Waves 1 to 3 feet. $$ LSZ267-182000- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 401 AM EDT Mon May 18 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 8 PM EDT THIS EVENING... .EARLY THIS MORNING...Southeast winds 20 to 30 knots. Patchy fog. Rain showers likely and a chance of thunderstorms. Waves 3 to 6 feet occasionally to 8 feet. .TODAY...Southeast winds 15 to 25 knots becoming southwest 10 to 20 knots in the afternoon, then becoming north 5 to 15 knots late. Areas of dense fog. A slight chance of thunderstorms through early afternoon. A chance of showers. Waves subsiding to calm to 2 feet. .TONIGHT...East winds 5 to 15 knots becoming southeast 10 to 20 knots late. Areas of dense fog. A chance of showers and thunderstorms. Waves building to 2 to 4 feet. .TUESDAY...South winds 15 to 25 knots becoming west 20 to 30 knots in the afternoon, then increasing to 30 knots with a few gale force gusts to 35 knots possible late. Areas of dense fog through early afternoon. A slight chance of thunderstorms through early afternoon. A chance of rain showers. Waves building to 7 to 10 feet occasionally to 13 feet. .TUESDAY NIGHT...Northwest gales to 35 knots diminishing to 20 to 30 knots after midnight. Waves subsiding to 4 to 7 feet occasionally to 9 feet. .WEDNESDAY...Northwest winds 20 to 30 knots diminishing to 10 to 20 knots by mid afternoon. Waves subsiding to 2 to 4 feet. .WEDNESDAY NIGHT...West winds 5 to 15 knots backing south after midnight. Waves subsiding to calm to 2 feet. .THURSDAY...East winds 5 to 15 knots veering southeast. Waves calm to 2 feet. .FRIDAY...Southeast winds 10 to 20 knots. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. $$ LSZ261-181400- MAFOR 1809/ Superior West 11126 11120 12110 11120 11130 11136 11146. Waves 3 to 6 feet subsiding to 2 to 3 feet today. Waves 2 to 3 feet building to 5 to 7 feet tonight. Superior North Central 11336 19334 11324 12810 19814 11820 12130 11136. A chance of thunderstorms this morning. Waves 3 to 6 feet. Superior South Central 11326 19324 11320 19324 11420 19424 11710 19714 11820 11810 11114 11216. A chance of thunderstorms this morning. Waves 3 to 6 feet subsiding to 2 to 4 feet today. Waves 1 to 3 feet tonight. Superior East 12336 19334 11424 11614 11804 11104 11224 11234. Waves 3 to 6 feet subsiding to 2 to 4 feet today. Waves 1 to 2 feet building to 3 to 5 feet tonight. $$ 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