Great Lakes Forecast
Issued by NWS
Issued by NWS
210 FZUS63 KMQT 181954 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 354 PM EDT Tue Jun 18 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 weakening 29.5 inch low over Minnesota continues tracking into northern Ontario this evening, eventually reaching James Bay at 29.6 inches Wednesday morning as it pulls a 29.7 inch trough over Lake Superior the rest of today through this evening. As the low lifts northeast, high pressure to 30.4 inches builds over Lake Superior for Thursday and Friday. By Friday night, the high weakens to 30.2 inches and slides east. Low pressure of at least 29.7 inches lifts off of the Colorado Rockies Friday night and brings troughing of around 29.6 inches over Lake Superior Saturday as the low moves into Canada. The troughing over Lake Superior deepens to at least 29.5 inches by Sunday as the low strengthens over northern Ontario. LSZ162-190400- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 354 PM EDT Tue Jun 18 2024 /254 PM CDT Tue Jun 18 2024/ .LATE THIS AFTERNOON...South winds 15 to 25 knots. A chance of showers and thunderstorms. Waves 1 to 3 feet. .TONIGHT...South winds 15 to 25 knots becoming west 20 to 30 knots late. Showers and thunderstorms likely through midnight, then a chance of showers and thunderstorms after midnight. Waves building to 3 to 6 feet occasionally to 8 feet. .WEDNESDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots in the afternoon, then backing southwest late. Waves subsiding to calm to 2 feet. .WEDNESDAY NIGHT...West winds 5 to 15 knots veering north late. Waves calm to 2 feet. .THURSDAY...Northeast winds 5 to 15 knots increasing to 10 to 20 knots by mid afternoon. A slight chance of showers by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Northeast winds 5 to 15 knots. A chance of showers after midnight. Waves calm to 2 feet. .FRIDAY...Northeast winds 5 to 15 knots increasing to 10 to 20 knots by mid afternoon. Showers and a chance of thunderstorms. Waves building to 1 to 3 feet. .FRIDAY NIGHT...Northeast winds 10 to 20 knots. Showers and a chance of thunderstorms. Waves 1 to 3 feet. .SATURDAY...Northeast winds 15 to 25 knots backing west. Showers. A chance of thunderstorms. A chance of showers. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .SUNDAY...Northwest winds 15 to 25 knots becoming west 10 to 20 knots. A chance of showers. Waves subsiding to calm to 2 feet. $$ LSZ263-190400- Lake Superior from Saxon Harbor WI to Upper Entrance to Portage Canal MI 5NM off shore to the US/Canadian border including Isle Royale National Park- 354 PM EDT Tue Jun 18 2024 .LATE THIS AFTERNOON...South winds 15 to 25 knots. A slight chance of showers and thunderstorms. Waves 2 to 4 feet subsiding to 1 to 3 feet. .TONIGHT...South winds 10 to 20 knots increasing to 15 to 25 knots after midnight, then veering southwest late. A chance of showers and thunderstorms. Waves building to 3 to 6 feet occasionally to 8 feet. .WEDNESDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots in the afternoon. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 1 to 3 feet. .WEDNESDAY NIGHT...West winds 5 to 15 knots veering north late. Waves subsiding to calm to 2 feet. .THURSDAY...Northeast winds 5 to 15 knots veering east by mid afternoon. A slight chance of showers by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...East winds 5 to 15 knots. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots. A chance of showers through early afternoon. Showers likely by mid afternoon. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 5 to 15 knots. Showers and a chance of thunderstorms. Waves building to 1 to 3 feet. .SATURDAY...East winds 10 to 20 knots veering west. Showers and a chance of thunderstorms. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .SUNDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots. A chance of showers. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet. $$ LSZ264-190400- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 354 PM EDT Tue Jun 18 2024 .LATE THIS AFTERNOON...South winds 15 to 25 knots. Waves 3 to 6 feet occasionally to 8 feet building to 4 to 7 feet occasionally to 9 feet. .TONIGHT...South winds 15 to 25 knots diminishing to 10 to 20 knots after midnight, then increasing to 15 to 25 knots late. A chance of showers and thunderstorms. Waves subsiding to 3 to 6 feet occasionally to 8 feet. .WEDNESDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots late. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 2 to 4 feet. .WEDNESDAY NIGHT...West winds 5 to 15 knots becoming northwest less than 10 knots late. Waves subsiding to calm to 2 feet. .THURSDAY...Northeast winds 5 to 15 knots veering east by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Southwest winds less than 10 knots backing southeast after midnight. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots. A chance of showers. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 5 to 15 knots. A chance of showers through midnight. A chance of thunderstorms. Showers likely after midnight. Waves calm to 2 feet. .SATURDAY...Southeast winds 10 to 20 knots veering west. Showers and a chance of thunderstorms. Waves building to 2 to 4 feet. .SUNDAY...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots. A chance of showers. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 1 to 3 feet. $$ LSZ265-190400- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 354 PM EDT Tue Jun 18 2024 .LATE THIS AFTERNOON...South winds 20 to 30 knots. Waves 3 to 6 feet occasionally to 8 feet. .TONIGHT...South winds 15 to 25 knots. A chance of showers and thunderstorms. Waves subsiding to 1 to 3 feet. .WEDNESDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots late. A slight chance of showers and thunderstorms through early afternoon. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. .WEDNESDAY NIGHT...Northwest winds 5 to 15 knots backing west after midnight, then veering northwest late. Waves calm to 2 feet. .THURSDAY...North winds 5 to 15 knots veering northeast by mid afternoon. A slight chance of showers by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Southeast winds less than 10 knots backing east after midnight. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots. A chance of showers. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 5 to 15 knots veering southeast after midnight. Showers and a chance of thunderstorms. Waves calm to 2 feet. .SATURDAY...Southeast winds 10 to 20 knots becoming west 15 to 25 knots. Showers and a chance of thunderstorms. Waves calm to 2 feet. .SUNDAY...West winds 15 to 25 knots veering northwest. A chance of showers. Waves calm to 2 feet. $$ LSZ266-190400- 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- 354 PM EDT Tue Jun 18 2024 .LATE THIS AFTERNOON...South winds 20 to 30 knots. Waves 3 to 6 feet occasionally to 8 feet building to 4 to 7 feet occasionally to 9 feet. .TONIGHT...South winds 20 to 30 knots diminishing to 15 to 25 knots after midnight. A chance of showers and thunderstorms. Waves subsiding to 2 to 4 feet. .WEDNESDAY...West winds 15 to 25 knots diminishing to 10 to 20 knots late. A slight chance of showers and thunderstorms. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 2 to 4 feet. .WEDNESDAY NIGHT...Northwest winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .THURSDAY...North winds 5 to 15 knots. A slight chance of showers by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...North winds less than 10 knots. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots. A chance of showers. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 5 to 15 knots veering southeast after midnight. A chance of showers through midnight. A chance of thunderstorms. Showers after midnight. Waves calm to 2 feet. .SATURDAY...Southeast winds 10 to 20 knots veering west. Showers and a chance of thunderstorms. Waves building to 2 to 4 feet. .SUNDAY...West winds 15 to 25 knots veering northwest. A chance of showers. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet. $$ LSZ267-190400- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 354 PM EDT Tue Jun 18 2024 .LATE THIS AFTERNOON...South winds 20 to 30 knots. Waves 2 to 4 feet building to 3 to 5 feet occasionally to 7 feet. .TONIGHT...South winds 15 to 25 knots. A chance of showers and thunderstorms. Waves subsiding to 2 to 4 feet, then building to 3 to 5 feet occasionally to 7 feet. .WEDNESDAY...Southwest winds 15 to 25 knots veering west in the afternoon, then becoming northwest 10 to 20 knots late. A chance of showers and thunderstorms. Waves 2 to 4 feet. .WEDNESDAY NIGHT...Northwest winds 5 to 15 knots. Waves subsiding to calm to 2 feet. .THURSDAY...North winds 5 to 15 knots becoming northwest 10 to 20 knots by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...North winds 5 to 15 knots. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots. A chance of showers. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 5 to 15 knots becoming southeast 10 to 20 knots after midnight. A chance of showers through midnight. Showers likely after midnight. Waves calm to 2 feet. .SATURDAY...Southeast winds 10 to 20 knots veering south. Showers and a chance of thunderstorms. Waves building to 1 to 3 feet. .SUNDAY...West winds 15 to 25 knots becoming northwest 10 to 20 knots. A chance of showers. Waves building to 2 to 4 feet. $$ LSZ261-190400- MAFOR 1821/ Superior West 11420 11429 11436 11530 12630 12620. Waves 2 to 5 feet tonight. Waves 3 to 6 feet subsiding to 1 to 3 feet Wednesday. Superior North Central 11330 12430 11320 11540 13630. A chance of showers and thunderstorms tonight. Waves 3 to 6 feet building to 4 to 7 feet, then subsiding to 3 to 6 feet tonight. Waves 3 to 6 feet building to 4 to 7 feet Wednesday. Superior South Central 11330 11430 13420 13620. A chance of showers and thunderstorms overnight. Waves 3 to 6 feet subsiding to 1 to 4 feet tonight and Wednesday. Superior East 14430 11430 11530 11630 11620. A chance of showers and thunderstorms overnight and Wednesday morning. Waves 3 to 6 feet. $$ GS Experimental modernized open lake forecast is available online at weather.gov/mqt/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes