Great Lakes Forecast
Issued by NWS
Issued by NWS
336 FZUS63 KMQT 191358 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 958 AM EDT Thu Sep 19 2024 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 30.0 inch high pressure ridge will hold from Quebec into the Great Lakes region today. Meanwhile, a 29.3 inch low pressure over southeast Saskatchewan will track toward Lake Winnipeg today with its associated 29.6 inch trough sweeping east into Minnesota. As the low continues to track northeast to Hudson Bay on Friday, the associated trough will fill to 29.8 inches as it moves over western Lake Superior. This trough will then dissipate, allowing weak 29.9 inch ridging to anchor over the Upper Great Lakes on Saturday morning. A new low pressure of 29.6 inches over southern Manitoba Saturday morning will then track across far northern Ontario Saturday afternoon and night. Its associated 29.9 inch trough will sweep across Lake Superior during Saturday night and Sunday morning. In its wake, 30.1 inch high pressure will build from the Northern Plains into northern Ontario during Sunday and Monday. Also on Monday, a 29.7 inch low pressure will track northeast to southern Wisconsin. LSZ162-192200- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 958 AM EDT Thu Sep 19 2024 /858 AM CDT Thu Sep 19 2024/ .REST OF TODAY...East winds 10 to 20 knots veering southeast late. A chance of showers and thunderstorms. Waves calm to 2 feet. .TONIGHT...South winds 10 to 20 knots veering southwest late. A chance of showers and thunderstorms. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. .FRIDAY...Southwest winds 10 to 20 knots. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY NIGHT...West winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .SATURDAY...Southeast winds 5 to 15 knots becoming east 10 to 20 knots by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Northwest winds 10 to 20 knots increasing to 15 to 25 knots after midnight. A chance of showers and thunderstorms. Waves calm to 2 feet. .SUNDAY...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. .MONDAY...North winds 10 to 20 knots. Waves subsiding to calm to 2 feet. $$ LSZ263-192200- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 958 AM EDT Thu Sep 19 2024 .REST OF TODAY...South winds 5 to 15 knots backing southeast in the afternoon, then increasing to 10 to 20 knots late. A slight chance of showers. A slight chance of thunderstorms by mid afternoon. Waves calm to 2 feet building to 1 to 3 feet. .TONIGHT...South winds 10 to 20 knots. A chance of showers and thunderstorms. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY...Southwest winds 5 to 15 knots increasing to 10 to 20 knots in the afternoon, then veering west late. A slight chance of showers and thunderstorms through early afternoon. Waves building to 2 to 4 feet. .FRIDAY NIGHT...Southwest winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .SATURDAY...South winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 5 to 15 knots becoming northwest 10 to 20 knots after midnight. A chance of showers and thunderstorms. Waves calm to 2 feet. .SUNDAY...Northwest winds 10 to 20 knots. A chance of showers. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .MONDAY...North winds 15 to 25 knots becoming southeast 10 to 20 knots. Waves subsiding to calm to 2 feet. $$ LSZ264-192200- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 958 AM EDT Thu Sep 19 2024 .REST OF TODAY...South winds 5 to 15 knots becoming southeast 10 to 20 knots in the afternoon. Waves 1 to 3 feet building to 2 to 4 feet. .TONIGHT...Southeast winds 15 to 25 knots veering south after midnight, then diminishing to 10 to 20 knots late. A chance of showers and thunderstorms. Waves building to 3 to 6 feet occasionally to 8 feet. .FRIDAY...South winds 5 to 15 knots veering southwest in the afternoon. A slight chance of showers and thunderstorms. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet. .FRIDAY NIGHT...Southwest winds 5 to 15 knots diminishing to less than 10 knots after midnight. Waves subsiding to calm to 2 feet. .SATURDAY...South winds 5 to 15 knots backing southeast by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 5 to 15 knots becoming west 10 to 20 knots after midnight. A chance of showers. Waves calm to 2 feet. .SUNDAY...Northwest winds 10 to 20 knots. A chance of showers. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. .MONDAY...Northwest winds 15 to 25 knots becoming east 10 to 20 knots. Waves subsiding to calm to 2 feet, then building to 1 to 3 feet. $$ LSZ265-192200- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 958 AM EDT Thu Sep 19 2024 .REST OF TODAY...Southeast winds 10 to 20 knots increasing to 15 to 25 knots late. Waves calm to 2 feet building to 2 to 4 feet. .TONIGHT...Southeast winds 15 to 25 knots veering south after midnight, then diminishing to 10 to 20 knots late. A chance of showers and thunderstorms. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet. .FRIDAY...South winds 10 to 20 knots becoming west 5 to 15 knots late. A chance of showers and thunderstorms. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...Southwest winds 5 to 15 knots. A slight chance of showers through midnight. Waves calm to 2 feet. .SATURDAY...Southwest winds 5 to 15 knots backing southeast by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 10 to 20 knots veering south after midnight. A chance of showers. Waves calm to 2 feet. .SUNDAY...Northwest winds 10 to 20 knots. A chance of showers. Waves calm to 2 feet. .MONDAY...North winds 10 to 20 knots veering east. A chance of showers. Waves calm to 2 feet. $$ LSZ266-192200- 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- 958 AM EDT Thu Sep 19 2024 .REST OF TODAY...South winds 10 to 20 knots backing southeast in the afternoon. Waves 1 to 3 feet building to 2 to 4 feet. .TONIGHT...South winds 15 to 25 knots. A slight chance of showers through midnight. A chance of thunderstorms. Showers likely after midnight. Waves building to 3 to 6 feet occasionally to 8 feet. .FRIDAY...South winds 10 to 20 knots. A chance of showers and thunderstorms. Waves subsiding to 1 to 3 feet. .FRIDAY NIGHT...South winds 5 to 15 knots veering southwest after midnight. A chance of showers and a slight chance of thunderstorms. Waves subsiding to calm to 2 feet. .SATURDAY...South winds 5 to 15 knots backing southeast by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 10 to 20 knots veering south after midnight. A chance of showers. Waves calm to 2 feet. .SUNDAY...Northwest winds 10 to 20 knots. A chance of showers. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. .MONDAY...North winds 10 to 20 knots veering east. A chance of showers. Waves subsiding to calm to 2 feet. $$ LSZ267-192200- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 958 AM EDT Thu Sep 19 2024 .REST OF TODAY...Southeast winds 10 to 20 knots veering south late. Waves calm to 2 feet. .TONIGHT...Southeast winds 10 to 20 knots increasing to 15 to 25 knots after midnight, then becoming south 10 to 20 knots late. A chance of showers and a slight chance of thunderstorms after midnight. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY...Southeast winds 10 to 20 knots. Showers likely through early afternoon. A chance of thunderstorms. A chance of showers by mid afternoon. Waves subsiding to calm to 2 feet. .FRIDAY NIGHT...South winds 5 to 15 knots. Showers likely through midnight. A slight chance of thunderstorms. A chance of showers after midnight. Waves calm to 2 feet. .SATURDAY...South winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .SATURDAY NIGHT...Southeast winds 10 to 20 knots. A chance of showers. Waves calm to 2 feet. .SUNDAY...Northwest winds 10 to 20 knots. A chance of showers. Waves building to 1 to 3 feet. .MONDAY...North winds 10 to 20 knots veering east. A chance of showers. Waves subsiding to calm to 2 feet. $$ LSZ261-192200- MAFOR 1915/ Superior West 13310 13420 11520 11510. A chance of showers late this morning. A chance of showers and thunderstorms tonight. Waves 1 to 3 feet. Superior North Central 12320 12330 11430 11436 11426 11420. A chance of thunderstorms tonight and Friday morning. Waves 1 to 3 feet building to 2 to 4 feet this afternoon. Waves 3 to 6 feet tonight and Friday morning. Superior South Central 11320 13330 11420 11426 12420. A chance of thunderstorms overnight and Friday morning. Waves 1 to 3 feet this afternoon. Waves 3 to 5 feet subsiding to 2 to 4 feet tonight. Waves 2 to 4 feet Friday morning. Superior East 13310 11420 11320 12420 11326. Waves 1 to 2 feet this afternoon. Waves 1 to 3 feet building to 2 to 4 feet tonight. Waves 2 to 4 feet Friday morning. $$ Voss Experimental modernized open lake forecast is available online at weather.gov/mqt/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes