FZUS61 KBUF 111403 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1003 AM EDT Wed Mar 11 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...Low pressure will deepen to 29.2 inches as it moves from Lake Huron this evening to southern Quebec overnight before reaching the Canadian Maritimes Thursday evening. A ridge of high pressure averaging 30.1 inches will then build into the Ohio Valley and lower Great Lakes Thursday afternoon and evening before drifting to the eastern seaboard Friday. A 29.0 inch low will then move from the upper Great Lakes Friday morning to the Ottawa Valley Friday night while weakening to 29.4 inches. This low will continue east to the Canadian Maritimes Saturday as a 30.3 inch high builds into the lower Great Lakes. LOZ062-112100- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1003 AM EDT Wed Mar 11 2026 ...GALE WARNING IN EFFECT FROM THIS EVENING THROUGH THURSDAY MORNING... .THIS AFTERNOON...East winds 10 to 15 knots becoming southeast 15 to 20 knots. Rain and scattered thunderstorms. Waves 3 to 6 feet subsiding to 2 to 4 feet. .TONIGHT...Southwest winds 15 to 25 knots becoming west and increasing to 35 knot gales after midnight. A chance of rain showers through the early overnight. Waves 3 to 5 feet building to 10 to 14 feet. Waves occasionally around 18 feet. .THURSDAY...West gales to 35 knots diminishing to 30 knots. Waves 10 to 14 feet subsiding to 6 to 9 feet. Waves occasionally around 18 feet. .THURSDAY NIGHT...West winds 15 to 25 knots becoming southwest and diminishing to 10 to 15 knots. Waves 5 to 8 feet subsiding to 2 to 4 feet. Waves occasionally around 10 feet. .FRIDAY...Southeast winds to 30 knots becoming west and increasing to 35 knot gales. Rain and snow during the day, then rain likely with a chance of snow showers Friday night. Waves 3 to 6 feet building to 10 to 15 feet. Waves occasionally around 19 feet. .SATURDAY...West gales to 35 knots becoming northeast and diminishing to 15 to 20 knots. A chance of snow showers Saturday night. Waves 10 to 14 feet subsiding to 1 to 3 feet. Waves occasionally around 18 feet. .SUNDAY...East winds 15 to 25 knots becoming south and increasing to 35 knot gales. Snow and rain showers. Waves 3 to 5 feet building to 10 to 14 feet. Waves occasionally around 18 feet. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-112100- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1003 AM EDT Wed Mar 11 2026 ...GALE WARNING IN EFFECT FROM THIS EVENING THROUGH THURSDAY MORNING... .THIS AFTERNOON...Southeast winds 15 to 20 knots. Rain and scattered thunderstorms. Waves 3 to 5 feet subsiding to 2 to 4 feet. .TONIGHT...Southwest winds 15 to 25 knots becoming west and increasing to 35 knot gales after midnight. Rain showers with a chance of thunderstorms early, then rain showers likely late in the evening. A chance of rain showers after midnight. Waves 2 to 4 feet building to 13 to 17 feet. Waves occasionally around 22 feet. .THURSDAY...West gales to 35 knots diminishing to 30 knots. Waves 12 to 17 feet subsiding to 10 to 14 feet. Waves occasionally around 22 feet. .THURSDAY NIGHT...West winds to 30 knots diminishing to 10 to 15 knots overnight. Waves 9 to 12 feet subsiding to 3 to 5 feet. Waves occasionally around 15 feet. .FRIDAY...South winds 15 to 25 knots becoming west and increasing to 40 knot gales. Rain and snow during the day, then snow showers likely with rain Friday night. Waves 3 to 5 feet building to 14 to 18 feet. Waves occasionally around 23 feet. .SATURDAY...West gales to 40 knots becoming north and diminishing to 10 to 15 knots. A chance of snow showers. Waves 14 to 18 feet subsiding to 2 to 4 feet. Waves occasionally around 23 feet. .SUNDAY...East winds 15 to 25 knots becoming south and increasing to 40 knot gales. Rain showers with snow showers likely. Waves 3 to 5 feet building to 9 to 12 feet. Waves occasionally around 15 feet. Winds and waves higher in and near thunderstorms. $$ LOZ061-112100- MAFOR 1115/ ONTARIO WEST 1/2...GALE WARNING IN EFFECT...12216 19219 11530 11640 13650 11640. A chance of rain showers tonight. Waves 3 to 5 feet subsiding to 2 to 4 feet this afternoon. Waves 3 to 5 feet building to 11 to 15 feet, and occasionally around 19 feet tonight. Waves 10 to 15 feet, and occasionally around 19 feet Thursday morning. ONTARIO EAST 1/2...GALE WARNING IN EFFECT...11310 11316 19319 11436 19439 11540 14650. Waves 2 to 4 feet this afternoon. Waves 2 to 4 feet building to 13 to 17 feet, and occasionally around 22 feet tonight. Waves 12 to 17 feet, and occasionally around 22 feet Thursday morning. $$