463 FZUS61 KBUF 191402 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1002 AM EDT Tue May 19 2026 For waters beyond five nautical miles of shore on Lake Ontario 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...An 29.6 inch area of low pressure over the upper Great Lakes this morning, will move northeast into central Quebec by Wednesday morning while strengthening to 29.4 inches. A cold front attendant to this low will cross the Lake tonight into Wednesday morning, bringing a round of thunderstorms to pass across the lake. A large 30.4 inch high will then build across the entire Great Lakes region Wednesday afternoon through Thursday, before sliding east off the New England coast late Friday. A 29.9 inch low and attendant warm front will then slowly approach the Lake later Friday night and Saturday. LOZ062-192100- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1002 AM EDT Tue May 19 2026 .THIS AFTERNOON...Southwest winds 15 to 20 knots. Waves 2 to 4 feet building to 3 to 5 feet. .TONIGHT...Southwest winds 15 to 20 knots becoming west. Showers with a chance of thunderstorms in the evening, then showers likely after midnight. Waves 3 to 5 feet. .WEDNESDAY...Northwest winds 10 to 15 knots becoming west. A chance of showers in the morning. Waves 2 to 4 feet subsiding to 1 to 3 feet. .WEDNESDAY NIGHT...Northwest winds 10 to 15 knots becoming north. Waves 1 to 3 feet. .THURSDAY...Northeast winds 5 to 15 knots becoming east 10 knots or less. Waves 2 feet or less. .FRIDAY...East winds 10 to 15 knots increasing to 15 to 20 knots. Showers likely Friday night. Waves 2 feet or less building to 3 to 5 feet. .SATURDAY...East winds 15 to 25 knots diminishing to 10 to 15 knots. Showers likely. Waves 4 to 7 feet subsiding to 2 to 4 feet. Waves occasionally around 9 feet. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-192100- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1002 AM EDT Tue May 19 2026 .THIS AFTERNOON...Southwest winds 10 to 15 knots. Waves 1 to 3 feet building to 2 to 4 feet. .TONIGHT...Southwest winds 10 to 15 knots becoming west 15 to 20 knots. A chance of showers and thunderstorms early, then showers with a chance of thunderstorms. A chance of showers late. Waves 2 to 4 feet. .WEDNESDAY...West winds 15 to 20 knots. A chance of showers in the morning. Waves 2 to 4 feet building to 3 to 6 feet. .WEDNESDAY NIGHT...West winds 15 to 20 knots becoming north 10 to 15 knots. Waves 3 to 6 feet subsiding to 1 to 3 feet. .THURSDAY...Northeast winds 5 to 15 knots diminishing to less than 10 knots. Waves 1 to 3 feet subsiding to 1 foot or less. .FRIDAY...East winds 5 to 15 knots increasing to 15 to 20 knots. Showers likely Friday night. Waves 1 to 3 feet building to 2 to 4 feet. .SATURDAY...East winds 15 to 25 knots becoming southeast. Showers. Waves 3 to 6 feet subsiding to 2 to 4 feet. Winds and waves higher in and near thunderstorms. $$ LOZ061-192100- MAFOR 1915/ ONTARIO WEST 1/2 13520 11526 11520 11620 12610. A chance of thunderstorms this evening. Waves 2 to 4 feet building to 3 to 5 feet this afternoon. Waves 3 to 5 feet tonight. Waves 2 to 4 feet Wednesday morning. ONTARIO EAST 1/2 14510 11526 11520 11610 11620. A chance of thunderstorms this evening. Waves 1 to 3 feet this afternoon. Waves 1 to 3 feet building to 2 to 4 feet tonight. Waves 2 to 4 feet Wednesday morning. $$  497 FZUS61 KBUF 191403 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 1003 AM EDT Tue May 19 2026 SLZ022-024-192100- Saint Lawrence River from Cape Vincent to Saint Regis 1003 AM EDT Tue May 19 2026 .THIS AFTERNOON...Southwest winds 10 to 15 knots. A chance of showers. .TONIGHT...Southwest winds 10 to 15 knots. A chance of showers through the early overnight, then showers likely late. .WEDNESDAY...Southwest winds 5 to 15 knots becoming northwest. A chance of showers in the morning. .WEDNESDAY NIGHT...Northwest winds 5 to 15 knots becoming north. Mainly clear. .THURSDAY...North winds 5 to 10 knots becoming light and variable. Mainly clear, then becoming partly cloudy. .FRIDAY...Light and variable winds. A chance of showers Friday night. .SATURDAY...East winds 10 knots or less. Showers likely. $$  586 FZUS63 KMKX 191405 GLFLM OPEN LAKE FORECAST for Lake Michigan National Weather Service Milwaukee/Sullivan WI 905 AM CDT Tue May 19 2026 FOR WATERS BEYOND FIVE NAUTICAL MILES OF SHORE ON Lake Michigan. Waves are provided as a range of significant wave heights, which is the average of the highest 1/3 of the wave, along with the average height of the highest 10% of the waves which will occasionally be encountered. .SYNOPSIS... A Dense Fog Advisory is in effect through Noon CDT for the north half of the lake as relatively mild and humid air flows over the cold lake waters. Otherwise modest to breezy southerly winds continue from now into early this afternoon. The gusty winds will be followed by the passage of a cold front late this afternoon as low pressure of 29.6 inches lifts from northern Lake Superior to central Quebec. Winds will shift to northwesterly with the cold frontal passage and remain a bit breezy. High pressure around 30.4 inches will then move into the northern Great Lakes for Wednesday afternoon into Thursday. Light to modest north to northeast winds can be expected. LMZ261-362-364-366-563-565-567-868-192115- Lake Michigan from Seul Choix Point to Rock Island Passage 5 NM offshore to Mid Lake- Lake Michigan South of a line from Seul Choix Point to the Mackinac Bridge and north of a line from Charlevoix MI to South Fox Island 5 NM offshore- Lake Michigan from Charlevoix to Point Betsie MI 5 NM offshore to Mid Lake- Lake Michigan from Point Betsie to Manistee MI 5 NM offshore to Mid Lake- Lake Michigan from Rock Island Passage to Sturgeon Bay WI- Lake Michigan from Sturgeon Bay to Two Rivers WI 5 NM offshore to Mid Lake- Lake Michigan from Two Rivers to Sheboygan WI 5 NM offshore to Mid Lake- Lake Michigan from Pentwater to Manistee MI 5 NM offshore to Mid Lake- 905 AM CDT Tue May 19 2026 SHEBOYGAN WI TO PENTWATER MI NORTH... ...DENSE FOG ADVISORY IN EFFECT UNTIL NOON CDT TODAY... .REST OF TODAY...South winds to 30 kt veering to west 15 to 25 kt. Areas of dense fog late this morning, then patchy fog this afternoon. Slight chance of showers late this morning, then chance of showers this afternoon. Waves 5 to 8 ft occasionally to 10 ft subsiding to 4 to 6 ft occasionally to 8 ft. .TONIGHT...Northwest winds 15 to 25 kt diminishing to 10 to 20 kt. Waves 3 to 5 ft subsiding to 2 to 4 ft. .WEDNESDAY...North winds 10 to 20 kt becoming northeast 15 to 25 kt. Waves 2 to 4 ft. .WEDNESDAY NIGHT...Northeast winds 10 to 20 kt diminishing to 10 to 15 kt. Waves 2 to 4 ft subsiding to 1 to 2 ft. .THURSDAY...Northeast winds 10 to 15 kt increasing to 10 to 20 kt. Waves 1 to 3 ft. .THURSDAY NIGHT...Northeast winds 10 to 20 kt becoming east 10 to 15 kt. Waves 1 to 3 ft. .FRIDAY...East winds 10 to 20 kt becoming northeast 15 to 25 kt. Waves 1 to 3 ft building to 3 to 5 ft. .SATURDAY...Northeast winds to 30 kt diminishing to 15 to 25 kt. Waves 3 to 5 ft. $$ LMZ080-669-671-673-675-777-779-870-872-874-876-878-192115- Lake Michigan from Michigan City IN to St. Joseph MI 5 NM offshore to Mid Lake- Lake Michigan from Sheboygan to Port Washington WI 5 NM offshore to Mid Lake- Lake Michigan from Port Washington to North Point Light WI 5 NM offshore to Mid Lake- Lake Michigan from North Point Light to Wind Point WI 5 NM offshore to Mid Lake- Lake Michigan from Wind Point WI to Winthrop Harbor IL 5 NM offshore to Mid Lake- Lake Michigan from Winthrop Harbor to Wilmette Harbor IL 5 NM offshore to Mid Lake- Lake Michigan from Wilmette Harbor IL to Michigan City IN 5 NM offshore to Mid Lake- Lake Michigan from Whitehall to Pentwater MI 5 NM offshore to Mid Lake- Lake Michigan from Grand Haven to Whitehall MI 5 NM offshore to Mid Lake- Lake Michigan from Holland to Grand Haven MI 5 NM offshore to Mid Lake- Lake Michigan from South Haven to Holland MI 5 NM offshore to Mid Lake- Lake Michigan from St. Joseph to South Haven MI 5 NM offshore to Mid Lake- 905 AM CDT Tue May 19 2026 SHEBOYGAN WI TO PENTWATER MI SOUTH... .REST OF TODAY...South winds to 30 kt becoming west 15 to 25 kt. Patchy fog late this morning. Slight chance of showers late this morning, then chance of showers and slight chance of thunderstorms this afternoon. Waves 5 to 8 ft occasionally to 10 ft subsiding to 3 to 5 ft. .TONIGHT...Northwest winds 10 to 20 kt becoming north 15 to 25 kt. Waves 3 to 5 ft. .WEDNESDAY...North winds 10 to 20 kt increasing to 15 to 25 kt. Waves 4 to 6 ft occasionally to 8 ft. .WEDNESDAY NIGHT...Northeast winds 15 to 25 kt diminishing to 10 to 20 kt. Waves 4 to 6 ft occasionally to 8 ft. .THURSDAY...Northeast winds 10 to 20 kt. Waves 2 to 4 ft. .THURSDAY NIGHT...Northeast winds 10 to 20 kt becoming east. Waves 3 to 5 ft. .FRIDAY...East winds 10 to 20 kt becoming northeast. Chance of showers. Waves 3 to 5 ft. .SATURDAY...Northeast winds 10 to 20 kt becoming north 10 to 15 kt. Waves 2 to 4 ft. $$ LMZ761-192115- MAFOR 1916/ MICHIGAN NORTH 11540 11640 11720 12730 11720 12820. A chance of showers this afternoon. Waves 4 to 7 feet subsiding to 3 to 6 feet this afternoon. Waves 3 to 5 feet subsiding to 1 to 3 feet tonight and Wednesday morning. MICHIGAN SOUTH 11540 11630 12720 12730 11830 11820. A chance of showers and a slight chance of thunderstorms this afternoon. Waves 3 to 6 feet this afternoon. Waves 2 to 4 feet subsiding to 1 to 3 feet tonight and Wednesday morning. $$ Cronce Experimental modernized open lake forecast is available online at weather.gov/mkx/glftable Graphical marine forecasts are available online at: weather.gov/greatlakes  401 FZUS63 KMQT 191401 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 1001 AM EDT Tue May 19 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 eastern Lake Superior this morning moves to the Ontario/Quebec line south of James Bay at 29.6 inches by this evening. Afterwards, a 30.2 inch high over the Northern Plains builds to 30.4 inches tonight into Wednesday as it tracks eastward into the Upper Great Lakes. The high pressure shifts east on Thursday while leaving lingering ridging of at least 30.2 inches over Lake Superior into Friday. A 29.9 inch low lifts into the Lower Great Lakes from the Southern Plains on Saturday, but 30.1 inch ridging persists over Lake Superior. LSZ162-192000- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 1001 AM EDT Tue May 19 2026 /901 AM CDT Tue May 19 2026/ .REST OF TODAY...West winds 10 to 20 knots. Waves 2 to 4 feet subsiding to 1 to 3 feet. .TONIGHT...Northwest winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .WEDNESDAY...West winds 5 to 15 knots backing south in the afternoon. Waves calm to 2 feet. .WEDNESDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to 2 feet. .THURSDAY...Southeast winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...East winds 5 to 15 knots. Waves calm to 2 feet. .FRIDAY...Northeast winds 10 to 20 knots. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. .SATURDAY...Northeast winds 5 to 15 knots. A chance of rain showers. Waves calm to 2 feet. $$ LSZ263-192000- 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 AM EDT Tue May 19 2026 .REST OF TODAY...West winds 10 to 20 knots diminishing to 5 to 15 knots in the afternoon, then increasing to 10 to 20 knots late. Waves 3 to 5 feet occasionally to 7 feet subsiding to 2 to 4 feet. .TONIGHT...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 in the afternoon, then backing south late. Waves calm to 2 feet. .WEDNESDAY NIGHT...Southeast winds 5 to 15 knots veering south after midnight. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Southeast winds 5 to 15 knots veering south after midnight. Waves calm to 2 feet. .FRIDAY...East winds 10 to 20 knots. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. .SATURDAY...East winds 5 to 15 knots. Waves calm to 2 feet. $$ LSZ264-192000- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 1001 AM EDT Tue May 19 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM EDT THIS MORNING... .REST OF TODAY...Northwest winds 10 to 20 knots increasing to 15 to 25 knots in the afternoon, then diminishing to 10 to 20 knots late. A slight chance of rain showers by late morning. Waves 3 to 5 feet occasionally to 7 feet. .TONIGHT...North winds 10 to 20 knots backing northwest after midnight. Waves subsiding to 1 to 3 feet. .WEDNESDAY...Northwest winds 5 to 15 knots backing southwest late. Waves subsiding to calm to 2 feet. .WEDNESDAY NIGHT...South winds 5 to 15 knots. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing southeast by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Southeast winds 5 to 15 knots veering south after midnight. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots increasing to 10 to 20 knots. Waves calm to 2 feet. .SATURDAY...East winds 5 to 15 knots veering southeast. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. $$ LSZ265-192000- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 1001 AM EDT Tue May 19 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM EDT THIS MORNING... .REST OF TODAY...West winds 20 to 30 knots becoming northwest 15 to 25 knots late. Patchy fog by late morning. A slight chance of rain showers by late morning. Waves 2 to 4 feet building to 3 to 5 feet occasionally to 7 feet, then subsiding to 2 to 4 feet. .TONIGHT...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots late. Waves 2 to 4 feet. .WEDNESDAY...Northwest winds 10 to 20 knots veering north in the afternoon, then becoming southeast 5 to 15 knots late. Waves subsiding to calm to 2 feet. .WEDNESDAY NIGHT...South winds 5 to 15 knots. Waves calm to 2 feet. .THURSDAY...Southeast winds 5 to 15 knots becoming east 10 to 20 knots by mid afternoon. Waves building to 1 to 3 feet. .THURSDAY NIGHT...Southeast winds 10 to 20 knots becoming south 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .FRIDAY...East winds 10 to 20 knots. Waves building to 1 to 3 feet. .SATURDAY...East winds 10 to 20 knots veering southeast. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. $$ LSZ266-192000- Lake Superior East of a line from Manitou Island to Marquette MI and West of a line from Grand Marais MI to the US/Canadian Border Beyond 5NM from shore- 1001 AM EDT Tue May 19 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM EDT THIS MORNING... .REST OF TODAY...West winds 20 to 30 knots veering northwest in the afternoon. Patchy fog by late morning. A slight chance of rain showers. Waves 3 to 6 feet occasionally to 8 feet. .TONIGHT...Northwest winds 20 to 30 knots diminishing to 15 to 25 knots late. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .WEDNESDAY...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots in the afternoon, then becoming west 5 to 15 knots late. Waves subsiding to calm to 2 feet. .WEDNESDAY NIGHT...West winds 5 to 15 knots backing south after midnight. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing southeast by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Southeast winds 10 to 20 knots veering south after midnight. Waves calm to 2 feet. .FRIDAY...East winds 10 to 20 knots. Waves building to 1 to 3 feet. .SATURDAY...East winds 10 to 20 knots veering southeast. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. $$ LSZ267-192000- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 1001 AM EDT Tue May 19 2026 ...DENSE FOG ADVISORY IN EFFECT UNTIL 2 PM EDT THIS AFTERNOON... .REST OF TODAY...South winds 15 to 25 knots becoming west 20 to 30 knots in the afternoon, then veering northwest late. Patchy dense fog. A chance of rain showers. Waves 2 to 4 feet building to 3 to 6 feet occasionally to 8 feet. .TONIGHT...Northwest winds 20 to 30 knots. Waves building to 4 to 7 feet occasionally to 9 feet, then subsiding to 3 to 6 feet occasionally to 8 feet. .WEDNESDAY...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots late. Waves subsiding to 2 to 4 feet. .WEDNESDAY NIGHT...Northwest winds 5 to 15 knots backing west after midnight. Waves subsiding to calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing east by mid afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots increasing to 10 to 20 knots. Waves calm to 2 feet. .SATURDAY...East winds 10 to 20 knots becoming southeast 5 to 15 knots. Waves building to 1 to 3 feet, then subsiding to calm to 2 feet. $$ LSZ261-192000- MAFOR 1915/ Superior West 11610 12620 13710 12700. Waves 3 to 5 feet subsiding to 2 to 4 feet this afternoon. Waves 1 to 3 feet tonight. Waves 1 foot or less Wednesday morning. Superior North Central 14730 11730 12720 11710. Waves 3 to 5 feet this afternoon. Waves 3 to 5 feet subsiding to 2 to 4 feet tonight. Waves 1 to 3 feet Wednesday morning. Superior South Central 11630 11740 14730 11730 11720. Waves 3 to 5 feet this afternoon and tonight. Waves 3 to 5 feet subsiding to 2 to 4 feet Wednesday morning. Superior East 11534 11640 13730 11740 11730 11720. A chance of rain showers this afternoon. Waves 3 to 6 feet this afternoon. Waves 4 to 7 feet tonight. Waves 3 to 6 feet Wednesday morning. $$ 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