Great Lakes Forecast
Issued by NWS
Issued by NWS
454 FZUS63 KMQT 210901 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 400 AM EST Sat Feb 21 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 29.7 inch low over Lake Huron this morning gradually weakens to 30.0 inches by tonight as it slowly meanders into southern Ontario. Meanwhile, 31.2 inch high pressure builds over northern Saskatchewan. Through Sunday, the low is gradually absorbed into a 29.1 inch nor`easter off the Delmarva Peninsula as high pressure slides over Manitoba at 31.0 inches, extending 30.6 inch ridging over western Lake Superior. The high weakens slightly to 30.8 inches over northern Ontario by Monday afternoon before sharply weakening to 30.3 inches over the Ontario/Quebec line Tuesday morning. Meanwhile, broad 29.8 inch low pressure forms over the Plains, sending at least one low of around 29.5 inches through the Great Lakes basin during the midweek period. Weak ridging then builds over Lake Superior at around 29.9 inches for Thursday. LSZ162-212100- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 400 AM EST Sat Feb 21 2026 /300 AM CST Sat Feb 21 2026/ .EARLY THIS MORNING...Northwest winds 10 to 20 knots. A slight chance of snow showers. Waves 1 to 3 feet. .TODAY...Northwest winds 10 to 20 knots. A slight chance of snow showers. Waves 1 to 3 feet. .TONIGHT...Northwest winds 15 to 25 knots veering north by midnight, then increasing to 20 to 30 knots late. A slight chance of snow showers in the evening. Waves building to 3 to 5 feet occasionally to 7 feet. .SUNDAY...North winds 20 to 30 knots. A slight chance of snow showers in the morning. Waves building to 3 to 6 feet occasionally to 8 feet. .SUNDAY NIGHT...North winds 20 to 30 knots diminishing to 15 to 25 knots after midnight. Waves subsiding to 2 to 4 feet. .MONDAY...North winds 10 to 20 knots becoming east 5 to 15 knots in the afternoon. Waves subsiding to calm to 2 feet. .MONDAY NIGHT...Southeast winds 5 to 15 knots becoming south 10 to 20 knots after midnight. A chance of snow showers. Waves building to 1 to 3 feet. .TUESDAY...South winds 10 to 20 knots veering west. A chance of snow showers. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. .WEDNESDAY...Northwest winds 10 to 20 knots. A chance of snow showers. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. Note, wave height forecasts are for ice free areas. $$ LSZ263-212100- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 400 AM EST Sat Feb 21 2026 ...HEAVY FREEZING SPRAY WARNING IN EFFECT FROM SUNDAY MORNING THROUGH LATE SUNDAY NIGHT... .EARLY THIS MORNING...Northwest winds 10 to 20 knots. A chance of snow showers. Waves 2 to 4 feet. .TODAY...North winds 10 to 20 knots diminishing to 5 to 15 knots by late morning, then backing northwest by mid afternoon. A chance of snow showers. Waves subsiding to 1 to 3 feet. .TONIGHT...North winds 10 to 20 knots increasing to 15 to 25 knots by midnight. A chance of snow showers. Waves building to 3 to 6 feet occasionally to 8 feet. .SUNDAY...North winds 20 to 30 knots. Heavy freezing spray. A slight chance of snow showers. Waves building to 5 to 8 feet occasionally to 10 feet. .SUNDAY NIGHT...North gales to 35 knots. Heavy freezing spray. A slight chance of snow showers. Waves building to 7 to 10 feet occasionally to 13 feet, then subsiding to 5 to 8 feet occasionally to 10 feet. .MONDAY...North winds 15 to 25 knots diminishing to 5 to 15 knots in the afternoon. Waves subsiding to 1 to 3 feet. .MONDAY NIGHT...East winds 5 to 15 knots becoming south 10 to 20 knots after midnight. A chance of snow showers after midnight. Waves subsiding to calm to 2 feet, then building to 2 to 4 feet. .TUESDAY...South winds 10 to 20 knots becoming west 15 to 25 knots. A chance of snow showers. Waves building to 5 to 8 feet occasionally to 10 feet. .WEDNESDAY...Northwest winds 10 to 20 knots increasing to 15 to 25 knots. A chance of snow showers. Waves subsiding to 3 to 6 feet occasionally to 8 feet. Note, wave height forecasts are for ice free areas. $$ LSZ264-212100- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 400 AM EST Sat Feb 21 2026 ...HEAVY FREEZING SPRAY WARNING IN EFFECT FROM LATE TONIGHT THROUGH LATE SUNDAY NIGHT... ...GALE WATCH IN EFFECT FROM SUNDAY AFTERNOON THROUGH LATE SUNDAY NIGHT... .EARLY THIS MORNING...Northwest winds 10 to 20 knots. Snow showers. Waves 3 to 5 feet occasionally to 7 feet. .TODAY...North winds 10 to 20 knots diminishing to 5 to 15 knots by late morning, then increasing to 10 to 20 knots by mid afternoon. Snow showers. Waves subsiding to 2 to 4 feet. .TONIGHT...North winds 15 to 25 knots increasing to 20 to 30 knots late. A chance of snow showers. Freezing spray after midnight. Waves building to 4 to 7 feet occasionally to 9 feet. .SUNDAY...North winds 20 to 30 knots increasing to gales to 35 knots by mid afternoon. Heavy freezing spray. A slight chance of snow showers. Waves building to 7 to 10 feet occasionally to 13 feet. .SUNDAY NIGHT...North gales to 35 knots. Heavy freezing spray. A chance of snow showers. Waves building to 8 to 11 feet occasionally to 14 feet, then subsiding to 6 to 9 feet occasionally to 11 feet. .MONDAY...North winds 20 to 30 knots diminishing to 10 to 20 knots in the afternoon. Heavy freezing spray in the morning. A chance of snow showers. Waves subsiding to 2 to 4 feet. .MONDAY NIGHT...East winds 5 to 15 knots becoming southeast 10 to 20 knots after midnight. Waves subsiding to calm to 2 feet, then building to 2 to 4 feet. .TUESDAY...South winds 15 to 25 knots backing southeast. Freezing spray. A chance of snow showers. Waves building to 6 to 9 feet occasionally to 11 feet. .WEDNESDAY...Northwest winds 15 to 25 knots increasing to 20 to 30 knots. A chance of snow showers. Freezing spray. Waves subsiding to 3 to 6 feet occasionally to 8 feet, then building to 5 to 8 feet occasionally to 10 feet. Note, wave height forecasts are for ice free areas. $$ LSZ265-212100- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 400 AM EST Sat Feb 21 2026 ...HEAVY FREEZING SPRAY WARNING IN EFFECT FROM SUNDAY AFTERNOON THROUGH LATE SUNDAY NIGHT... ...GALE WATCH IN EFFECT FROM SUNDAY AFTERNOON THROUGH LATE SUNDAY NIGHT... .EARLY THIS MORNING...Northwest winds 20 to 30 knots. Freezing spray. Snow showers. Waves 3 to 6 feet occasionally to 8 feet. .TODAY...Northwest winds 15 to 25 knots increasing to 20 to 30 knots by mid afternoon. Snow showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .TONIGHT...Northwest winds 15 to 25 knots increasing to 20 to 30 knots by midnight, then veering north late. Snow showers likely in the evening, then a chance of snow showers after midnight. Freezing spray after midnight. Waves building to 5 to 8 feet occasionally to 10 feet. .SUNDAY...North gales to 35 knots. Freezing spray. A chance of snow showers. Waves building to 8 to 11 feet occasionally to 14 feet. .SUNDAY NIGHT...North gales to 40 knots. Heavy freezing spray. A chance of snow showers. Waves building to 8 to 12 feet occasionally to 15 feet. .MONDAY...North winds 20 to 30 knots diminishing to 10 to 20 knots in the afternoon. Heavy freezing spray. A chance of snow showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .MONDAY NIGHT...North winds 5 to 15 knots becoming south 10 to 20 knots after midnight. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet. .TUESDAY...South winds 15 to 25 knots. Freezing spray. A chance of snow showers. Waves building to 4 to 7 feet occasionally to 9 feet. .WEDNESDAY...Northwest winds 20 to 30 knots. Freezing spray. A chance of snow showers. Waves building to 4 to 8 feet occasionally to 10 feet. Note, wave height forecasts are for ice free areas. $$ LSZ266-212100- 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 AM EST Sat Feb 21 2026 ...HEAVY FREEZING SPRAY WARNING IN EFFECT FROM SUNDAY AFTERNOON THROUGH LATE SUNDAY NIGHT... ...GALE WATCH IN EFFECT FROM SUNDAY AFTERNOON THROUGH MONDAY MORNING... .EARLY THIS MORNING...Northwest winds 15 to 25 knots. A chance of snow showers. Waves 4 to 7 feet occasionally to 9 feet. .TODAY...Northwest winds 15 to 25 knots veering northeast by late morning, then backing north by mid afternoon. A chance of snow showers. Waves subsiding to 3 to 5 feet occasionally to 7 feet. .TONIGHT...North winds 15 to 25 knots. A chance of snow showers. Freezing spray after midnight. Waves building to 5 to 8 feet occasionally to 10 feet. .SUNDAY...North winds 20 to 30 knots increasing to gales to 35 knots by mid afternoon. Freezing spray. A chance of snow showers. Waves building to 8 to 11 feet occasionally to 14 feet. .SUNDAY NIGHT...North gales to 40 knots. Heavy freezing spray. A chance of snow showers. Waves building to 10 to 14 feet occasionally to 18 feet, then subsiding to 9 to 12 feet occasionally to 15 feet. .MONDAY...North winds 20 to 30 knots diminishing to 15 to 25 knots in the afternoon. Heavy freezing spray. A chance of snow showers. Waves subsiding to 3 to 6 feet occasionally to 8 feet. .MONDAY NIGHT...North winds 10 to 20 knots veering southeast after midnight. A chance of snow showers after midnight. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet. .TUESDAY...Southeast winds 15 to 25 knots increasing to 20 to 30 knots. Freezing spray. A chance of snow showers. Waves building to 5 to 8 feet occasionally to 10 feet. .WEDNESDAY...Northwest winds 20 to 30 knots increasing to gales to 35 knots. Freezing spray. A chance of snow showers. Waves building to 8 to 12 feet occasionally to 15 feet. Note, wave height forecasts are for ice free areas. $$ LSZ267-212100- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 400 AM EST Sat Feb 21 2026 ...HEAVY FREEZING SPRAY WARNING IN EFFECT FROM SUNDAY AFTERNOON THROUGH LATE SUNDAY NIGHT... .EARLY THIS MORNING...East winds 10 to 20 knots. Waves calm to 2 feet. .TODAY...East winds 10 to 20 knots diminishing to 5 to 15 knots by late morning, then backing northeast by mid afternoon. A slight chance of snow showers. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. .TONIGHT...Northeast winds 5 to 15 knots increasing to 10 to 20 knots by midnight. A slight chance of snow showers. Waves building to 1 to 3 feet. .SUNDAY...North winds 10 to 20 knots increasing to 20 to 30 knots. A slight chance of snow showers in the morning. Freezing spray in the afternoon. Waves building to 4 to 7 feet occasionally to 9 feet. .SUNDAY NIGHT...North gales to 35 knots. Heavy freezing spray. A slight chance of snow showers. Waves building to 5 to 9 feet occasionally to 11 feet. .MONDAY...North winds 20 to 30 knots diminishing to 15 to 25 knots in the afternoon. Heavy freezing spray in the morning. Waves subsiding to 2 to 4 feet. .MONDAY NIGHT...Northeast winds 10 to 20 knots veering east after midnight. Waves subsiding to calm to 2 feet. .TUESDAY...Southeast winds 15 to 25 knots increasing to 20 to 30 knots. Freezing spray. A chance of snow showers. Waves building to 4 to 7 feet occasionally to 9 feet. .WEDNESDAY...Northwest winds 20 to 30 knots veering north. Freezing spray. A chance of snow showers. Waves subsiding to 3 to 6 feet occasionally to 8 feet, then building to 7 to 10 feet occasionally to 13 feet. Note, wave height forecasts are for ice free areas. $$ LSZ261-211500- MAFOR 2110/ Superior West 12720 12710 11720 11820 12830. Waves 1 to 3 feet today. Waves 1 to 3 feet building to 3 to 5 feet tonight. Superior North Central...HEAVY FREEZING SPRAY WARNING IN EFFECT... 14827 11837 12830 11840. Waves 3 to 5 feet today. Waves 3 to 6 feet building to 5 to 7 feet tonight. Superior South Central 15737 11737 11741. Waves 3 to 6 feet today. Waves 3 to 6 feet building to 4 to 7 feet tonight. Superior East 13220 11110 11810 12110 11120. Waves 2 to 4 feet subsiding to 1 to 3 feet today. Waves 1 to 3 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