655 FZUS61 KBUF 201402 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1002 AM EDT Wed May 20 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...Behind a passing cold front this morning, a large 30.4 inch area of surface high pressure will build across the entire Great Lakes region through Thursday, before sliding east off the New England coast late Friday. This surface high will then strengthen to 30.6 inches as it anchors over Atlantic Canada through Sunday. A 29.9 inch low and attendant warm front will then slowly approach the Lake late Friday night and Saturday, before weakening and sliding eastward Sunday. A 30.1 inch high will settle across the region Monday. LOZ062-202100- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1002 AM EDT Wed May 20 2026 .THIS AFTERNOON...West winds 10 to 15 knots. Waves 1 to 3 feet. .TONIGHT...Northwest winds 10 to 15 knots becoming north. Waves 1 to 3 feet. .THURSDAY...Northeast winds 5 to 15 knots becoming southeast. Waves 2 feet or less. .THURSDAY NIGHT...East winds less than 10 knots. Waves 1 foot or less. .FRIDAY...East winds 15 to 20 knots. Showers likely Friday night. Waves 1 to 3 feet building to 2 to 4 feet. .SATURDAY...East winds to 30 knots becoming southeast and diminishing to 15 to 20 knots. Showers. Waves 5 to 8 feet subsiding to 3 to 6 feet. Waves occasionally around 10 feet. .SUNDAY...Southeast winds 15 to 20 knots diminishing to 5 to 15 knots. Showers likely. Waves 2 to 4 feet subsiding to 1 to 3 feet. $$ LOZ063>065-202100- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1002 AM EDT Wed May 20 2026 .THIS AFTERNOON...West winds 15 to 20 knots. Waves 3 to 6 feet. .TONIGHT...West winds 15 to 20 knots becoming north. Waves 3 to 6 feet subsiding to 1 to 3 feet. .THURSDAY...Northeast winds 15 to 20 knots becoming northwest 5 to 15 knots. Waves 1 to 3 feet. .THURSDAY NIGHT...West winds less than 10 knots. Waves 1 foot or less. .FRIDAY...East winds 5 to 15 knots increasing to 15 to 20 knots. A chance of showers Friday night. Waves 1 to 3 feet. .SATURDAY...Southeast winds 15 to 25 knots. Showers. Waves 3 to 5 feet building to 4 to 7 feet, then subsiding to 3 to 6 feet. Waves occasionally around 9 feet. .SUNDAY...Southeast winds 15 to 25 knots. Showers likely. Waves 3 to 5 feet subsiding to 1 to 3 feet. $$ LOZ061-202100- MAFOR 2015/ ONTARIO WEST 1/2 12620 13710 11800 12110. Waves 2 to 4 feet this afternoon. Waves 2 to 4 feet subsiding to 1 to 2 feet tonight. Waves 1 to 2 feet Thursday morning. ONTARIO EAST 1/2 13620 11720 12810 12110. Waves 3 to 6 feet this afternoon. Waves 3 to 6 feet subsiding to 1 to 3 feet tonight. Waves 1 to 3 feet Thursday morning. $$  692 FZUS61 KBUF 201403 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 1003 AM EDT Wed May 20 2026 SLZ022-024-202100- Saint Lawrence River from Cape Vincent to Saint Regis 1003 AM EDT Wed May 20 2026 .THIS AFTERNOON...West winds 10 to 15 knots. Mostly sunny. .TONIGHT...Northwest winds 5 to 10 knots becoming north. Mainly clear early, then becoming partly cloudy. .THURSDAY...North winds 10 knots or less. Sunny. .THURSDAY NIGHT...North winds less than 10 knots. Mainly clear in the evening, then becoming partly cloudy. .FRIDAY...East winds less than 10 knots. Partly cloudy, then becoming mostly cloudy. .SATURDAY...East winds 5 to 10 knots becoming southeast. A chance of showers during the day, then showers likely Saturday night. .SUNDAY...Southeast winds 5 to 10 knots becoming south. Showers likely. $$  922 FZUS63 KDTX 201409 GLFLH Open Lake Forecast for Lake Huron National Weather Service Detroit/Pontiac MI Issued by National Weather Service Grand Rapids MI 1009 AM EDT Wed May 20 2026 For waters beyond five nautical miles off shore on Lake Huron 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... High pressure, 30.40 inches, will start to build in over the Great Lakes this morning then slowly move east across the region through Friday morning. As this occurs, northwest flow will veer to the northeast and persist into Friday. LHZ361-202215- Lake Huron from 5NM east of Mackinac Bridge to Presque Isle Lt beyond 5 NM off shore- 1009 AM EDT Wed May 20 2026 .REST OF TODAY...Northwest winds 15 to 20 knots. Waves 3 to 5 feet. .TONIGHT...Northwest winds 15 to 20 knots becoming north 10 to 15 knots by midnight...then decreasing to 5 to 10 knots early in the morning. Waves 2 to 4 feet subsiding to 1 to 3 feet early in the morning. .THURSDAY...East winds 5 to 10 knots veering to the southeast early in the afternoon. Waves 2 feet or less. .THURSDAY NIGHT...East winds 5 to 10 knots early in the evening becoming light and variable...then becoming east 5 to 10 knots after midnight. Waves 2 feet or less. .FRIDAY...East winds 5 to 10 knots increasing to 20 to 25 knots with gusts to around 30 knots. A chance of showers late in the evening. Waves 1 to 3 feet building to 6 to 9 feet. Waves occasionally around 12 feet. .SATURDAY...East winds to 30 knots with gusts to 35 knot gales decreasing to 15 to 20 knots by midnight. Showers likely early in the morning...then a chance of showers . Waves 8 to 12 feet. Waves occasionally around 15 feet. .SUNDAY...East winds 10 to 15 knots becoming southeast 5 to 10 knots. Waves 3 to 5 feet subsiding to 1 to 3 feet . $$ LHZ362-363-202215- Lake Huron from Presque Isle Light to Sturgeon Point MI beyond 5NM off shore- Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off shore- 1009 AM EDT Wed May 20 2026 .REST OF TODAY...Northwest winds 15 to 20 knots veering to the north late in the afternoon. Waves 5 to 7 feet. Waves occasionally around 10 feet. .TONIGHT...North winds 15 to 20 knots decreasing to 10 to 15 knots after midnight. Waves 3 to 5 feet. .THURSDAY...Northeast winds 10 to 15 knots decreasing to 5 to 10 knots in the late morning and afternoon. Waves 2 to 4 feet subsiding to 1 to 3 feet in the late morning and afternoon. .THURSDAY NIGHT...Northeast winds 5 to 10 knots. Waves 1 to 3 feet. .FRIDAY...East winds 10 to 15 knots becoming northeast 15 to 20 knots late in the afternoon. A chance of showers late in the evening. Waves 1 to 3 feet building to 5 to 7 feet. Waves occasionally around 10 feet. .SATURDAY...East winds 20 to 25 knots with gusts to around 30 knots decreasing to 10 to 15 knots. Showers likely early in the morning...then a chance of showers . Waves 8 to 12 feet. Waves occasionally around 15 feet. .SUNDAY...Southeast winds 10 to 15 knots becoming light and variable. Waves 3 to 5 feet subsiding to 1 to 3 feet . $$ LHZ462>464-202215- Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore- Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore- Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore- 1009 AM EDT Wed May 20 2026 .REST OF TODAY...North winds 10 to 15 knots. Waves 3 to 5 feet. .TONIGHT...North winds 10 to 15 knots. Waves 3 to 5 feet. .THURSDAY...Northeast winds 10 to 15 knots. Waves 2 to 4 feet subsiding to 1 to 3 feet in the late morning and early afternoon...then building to 2 to 4 feet early in the afternoon. .THURSDAY NIGHT...North winds 10 to 15 knots veering to the east after midnight. Waves 2 to 4 feet subsiding to 1 to 3 feet after midnight. .FRIDAY...East winds 10 to 15 knots increasing to 15 to 20 knots with gusts to around 30 knots late in the afternoon. A chance of showers late in the afternoon. Rain showers likely late in the evening. Waves 3 to 5 feet building to 5 to 7 feet late in the evening. Waves occasionally around 10 feet. .SATURDAY...East winds 20 to 25 knots with gusts to around 30 knots becoming southeast 10 to 15 knots. Showers likely early in the morning. Rain showers in the late morning and early afternoon...then a chance of showers early in the evening. Waves 5 to 7 feet. Waves occasionally around 10 feet. .SUNDAY...Southeast winds 5 to 10 knots backing to the east by midnight. Waves 1 to 3 feet. $$ LHZ461-202215- MAFOR 2015/ HURON NORTH 14720 11710 12100 11200. Waves 3 to 5 feet this afternoon. Waves 3 to 5 feet subsiding to 1 to 3 feet tonight. Waves 2 feet or less Thursday morning. HURON SOUTH 11820 11810 11820 13810 12110. Waves 4 to 6 feet. Occasional wave height around 8 feet this afternoon. Waves 3 to 5 feet subsiding to 2 to 4 feet tonight. Waves 1 to 3 feet Thursday morning. $$ Thomas (GRR) Experimental modernized open lake forecast is available online at weather.gov/dtx/glftable (all lower case) Graphical marine forecasts are available online at weather.gov/greatlakes (all lower case)  204 FZUS63 KDTX 201411 GLFSC Lake St Clair Forecast National Weather Service Detroit/Pontiac MI Issued by National Weather Service Grand Rapids MI 1011 AM EDT Wed May 20 2026 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... High pressure, 30.40 inches, will start to build in over the Great Lakes this morning then slowly move east across the region through Friday morning. As this occurs, northwest flow will veer to the northeast and persist into Friday. LCZ460-210215- Lake St Clair- 1011 AM EDT Wed May 20 2026 .REST OF TODAY...North winds 10 to 15 knots diminishing to 5 to 10 knots early in the afternoon...then becoming northeast 10 to 15 knots late in the afternoon. Mostly cloudy. Waves 2 feet or less. .TONIGHT...Northeast winds 15 to 20 knots. Mostly cloudy this evening becoming partly cloudy. Waves 1 to 3 feet. .THURSDAY...Northeast winds 10 to 15 knots. Mostly sunny. Waves 2 feet or less. .THURSDAY NIGHT...Northeast winds 10 to 15 knots increasing to 15 to 20 knots after midnight. Partly cloudy becoming mostly cloudy. Waves 1 to 3 feet. .FRIDAY...East winds 20 to 25 knots increasing to 30 knots in the evening. Mostly cloudy. A chance of light showers in the afternoon. Rain showers likely in the evening. Waves 2 to 4 feet. A Small Craft Advisory may be needed. .SATURDAY...Southeast winds to 30 knots. Showers and a chance of thunderstorms. Waves 2 to 4 feet. .SUNDAY...Northeast winds 10 to 15 knots. Mostly cloudy. Waves 2 feet or less. $$ Thomas (GRR) Experimental modernized open lake forecast is available online at weather.gov/dtx/glftablesc Graphical marine forecasts are available at weather.gov/greatlakes  816 FZUS63 KMQT 201427 GLFLS Open Lake Forecast for Lake Superior National Weather Service Marquette MI 1026 AM EDT Wed May 20 2026 For waters beyond 5 nautical miles of shore on Lake Superior. Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum. .SYNOPSIS... A 30.3 inch high over the Northern Plains shifts over Lake Superior today and builds to 30.4 inches tonight. The high pressure shifts east Thursday night while leaving lingering ridging of at least 30.3 inches over Lake Superior through Friday. A 29.9 inch low then lifts into the Lower Great Lakes from the Southern Plains Friday night and Saturday, but 30.1 inch ridging persists over Lake Superior the remainder of the weekend. LSZ162-202000- Lake Superior west of a line from Saxon Harbor WI to Grand Portage MN beyond 5NM- 1026 AM EDT Wed May 20 2026 /926 AM CDT Wed May 20 2026/ .REST OF TODAY...Southeast winds 5 to 15 knots veering south in the afternoon. Waves calm to 2 feet. .TONIGHT...Southeast winds 5 to 15 knots backing northeast after midnight. Waves calm to 2 feet. .THURSDAY...East winds 5 to 15 knots. Waves calm to 2 feet. .THURSDAY NIGHT...Northeast winds 5 to 15 knots. Waves calm to 2 feet. .FRIDAY...East winds 10 to 20 knots becoming northeast 15 to 25 knots by mid afternoon. Waves building to 2 to 4 feet. .FRIDAY NIGHT...Northeast winds 15 to 25 knots diminishing to 10 to 20 knots after midnight. Waves subsiding to 1 to 3 feet. .SATURDAY...Northeast winds 10 to 20 knots diminishing to 5 to 15 knots. A chance of rain showers. Waves building to 2 to 4 feet, then subsiding to calm to 2 feet. .SUNDAY...Southwest winds 5 to 15 knots. Waves calm to 2 feet. $$ LSZ263-202000- 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- 1026 AM EDT Wed May 20 2026 .REST OF TODAY...North winds less than 10 knots becoming south 5 to 15 knots in the afternoon. Waves calm to 2 feet. .TONIGHT...South winds 5 to 15 knots becoming southeast less than 10 knots after midnight, then becoming south 5 to 15 knots late. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing east late. Waves calm to 2 feet. .THURSDAY NIGHT...East winds 5 to 15 knots veering southeast after midnight. Waves calm to 2 feet. .FRIDAY...East winds 5 to 15 knots increasing to 10 to 20 knots by mid afternoon. Waves building to 2 to 4 feet. .FRIDAY NIGHT...East winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves subsiding to 1 to 3 feet. .SATURDAY...East winds 10 to 20 knots diminishing to 5 to 15 knots. A chance of rain showers. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .SUNDAY...Southwest winds 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ264-202000- Lake Superior from Upper Entrance to Portage Canal to Manitou Island MI 5NM off shore to the US/Canadian Border- 1026 AM EDT Wed May 20 2026 .REST OF TODAY...North winds 5 to 15 knots backing northwest in the afternoon, then backing southwest late. Waves calm to 2 feet. .TONIGHT...Southwest winds 5 to 15 knots diminishing to less than 10 knots after midnight, then backing south late. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing southeast in the afternoon. Waves calm to 2 feet. .THURSDAY NIGHT...Southeast winds 5 to 15 knots. Waves calm to 2 feet. .FRIDAY...Southeast winds 5 to 15 knots becoming east 10 to 20 knots by mid afternoon. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves building to 1 to 3 feet. .SATURDAY...East winds 10 to 20 knots becoming southeast 5 to 15 knots. A chanceof rain showers. Waves building to 2 to 4 feet, then subsiding to 1 to 3 feet. .SUNDAY...Southwest winds 5 to 15 knots. Waves subsiding to calm to 2 feet. $$ LSZ265-202000- Lake Superior West of Line from Manitou Island to Marquette MI Beyond 5NM from shore- 1026 AM EDT Wed May 20 2026 .REST OF TODAY...North winds 5 to 15 knots veering northeast late. Waves calm to 2 feet. .TONIGHT...South winds 5 to 15 knots. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots becoming east 10 to 20 knots in the afternoon, then increasing to 15 to 25 knots late. Waves building to 1 to 3 feet. .THURSDAY NIGHT...Southeast winds 10 to 20 knots diminishing to 5 to 15 knots after midnight. Waves subsiding to calm to 2 feet. .FRIDAY...East winds 10 to 20 knots increasing to 15 to 25 knots by mid afternoon. Waves building to 2 to 4 feet. .FRIDAY NIGHT...East winds 15 to 25 knots. Waves subsiding to 1 to 3 feet, then building to 2 to 4 feet. .SATURDAY...East winds 15 to 25 knots becoming southeast 10 to 20 knots. A chance of rain showers. Waves building to 3 to 6 feet occasionally to 8 feet, then subsiding to 1 to 3 feet. .SUNDAY...Southwest winds 10 to 20 knots backing south. Waves subsiding to calm to 2 feet. $$ LSZ266-202000- Lake Superior East of a line from Manitou Island to Marquette MI and West of a line from Grand Marais MI to the US/Canadian Border Beyond 5NM from shore- 1026 AM EDT Wed May 20 2026 .REST OF TODAY...Northwest winds 10 to 20 knots diminishing to 5 to 15 knots late. Waves 2 to 4 feet subsiding to calm to 2 feet. .TONIGHT...Northwest winds 5 to 15 knots backing southwest after midnight, then backing south late. Waves calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing southeast in the afternoon, then becoming east 10 to 20 knots late. Waves calm to 2 feet. .THURSDAY NIGHT...Southeast winds 10 to 20 knots becoming south 5 to 15 knots after midnight. Waves calm to 2 feet. .FRIDAY...Southeast winds 5 to 15 knots becoming east 10 to 20 knots by mid afternoon. Waves building to 1 to 3 feet. .FRIDAY NIGHT...East winds 15 to 25 knots diminishing to 10 to 20 knots after midnight. Waves building to 2 to 4 feet. .SATURDAY...East winds 15 to 25 knots becoming southeast 10 to 20 knots. A chance of rain showers. Waves building to 3 to 6 feet occasionally to 8 feet, then subsiding to 1 to 3 feet. .SUNDAY...Southwest winds 5 to 15 knots backing south. Waves subsiding to calm to 2 feet. $$ LSZ267-202000- Lake Superior from Grand Marais MI to Whitefish Point MI 5NM off shore to the US/Canadian border- 1026 AM EDT Wed May 20 2026 .REST OF TODAY...Northwest winds 15 to 25 knots diminishing to 10 to 20 knots late. Waves 2 to 4 feet subsiding to 1 to 3 feet. .TONIGHT...Northwest winds 5 to 15 knots backing south late. Waves subsiding to calm to 2 feet. .THURSDAY...South winds 5 to 15 knots backing northeast in the afternoon, then veering east late. 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. Waves calm to 2 feet. .FRIDAY NIGHT...East winds 10 to 20 knots increasing to 15 to 25 knots after midnight. Waves building to 2 to 4 feet. .SATURDAY...East winds 15 to 25 knots becoming southeast 10 to 20 knots. A chance of rain showers. Waves building to 3 to 5 feet occasionally to 7 feet, then subsiding to calm to 2 feet. .SUNDAY...South winds 5 to 15 knots. Waves calm to 2 feet. $$ LSZ261-202000- MAFOR 2015/ Superior West 11300 11410 11400 14300 11300. Waves 1 foot or less. Superior North Central 11710 11600 12510 12500 12400. Waves 2 feet or less. Superior South Central 11810 11800 11100 14400 11400. Waves 1 to 3 feet this afternoon. Waves 2 feet or less tonight and Thursday morning. Superior East 12720 12710 11700 11600 1150011400. Waves 2 to 4 feet this afternoon. Waves 1 to 3 feet tonight. Waves 1 foot or less Thursday morning. $$ 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