FZUS61 KBUF 121327 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 927 AM EDT Thu Mar 12 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...A ridge of high pressure averaging 30.1 inches will build into the Ohio Valley and lower Great Lakes this 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. A 30.3 inch surface high will ridge across the lake Saturday night, and move east of the lake Sunday. Meanwhile, a 29.5 inch surface low over the mid Mississippi Valley Sunday morning will track northeastward and deepen to 28.9 inches just to the west of the lake Monday morning. LOZ062-122115- Lake Ontario open waters from the Niagara River to Hamlin Beach- 927 AM EDT Thu Mar 12 2026 ...GALE WATCH IN EFFECT FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING... .REST OF TODAY...West winds to 30 knots diminishing to 15 to 20 knots. Scattered snow showers early this afternoon. Waves 7 to 10 feet subsiding to 5 to 8 feet. Waves occasionally around 13 feet. .TONIGHT...Northwest winds 15 to 20 knots becoming south 5 to 15 knots. Waves 3 to 6 feet subsiding to 1 to 2 feet. .FRIDAY...Southeast winds 15 to 25 knots becoming southwest to 30 knots. Snow showers in the morning, then rain and snow showers in the afternoon. Waves 1 to 3 feet building to 5 to 9 feet. Waves occasionally around 11 feet. .FRIDAY NIGHT...Southwest winds to 30 knots becoming west and increasing to 40 knot gales overnight. Rain showers with a chance of snow showers in the evening, then a chance of snow showers overnight. Waves 7 to 10 feet building to 13 to 18 feet. Waves occasionally around 23 feet. .SATURDAY...West gales to 35 knots becoming northeast and diminishing to 10 to 15 knots. A chance of snow showers Saturday night. Waves 12 to 16 feet subsiding to 1 to 3 feet. Waves occasionally around 20 feet. .SUNDAY...East winds 15 to 20 knots becoming southeast and increasing to 30 knots. Snow showers with rain showers likely. Waves 3 to 5 feet building to 7 to 11 feet. Waves occasionally around 14 feet. .MONDAY...South gales to 35 knots becoming west to 40 knots. Rain showers with a chance of snow showers during the day, then a chance of snow and rain showers Monday night. Waves 8 to 11 feet building to 14 to 19 feet. Waves occasionally around 24 feet. $$ LOZ063>065-122115- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 927 AM EDT Thu Mar 12 2026 ...GALE WATCH IN EFFECT FROM FRIDAY EVENING THROUGH SATURDAY AFTERNOON... .REST OF TODAY...West winds to 30 knots. Scattered snow showers late this morning. Waves 10 to 13 feet subsiding to 8 to 11 feet. Waves occasionally around 16 feet. .TONIGHT...Northwest winds to 30 knots becoming west and diminishing to 5 to 15 knots after midnight. Waves 7 to 10 feet subsiding to 2 to 4 feet. Waves occasionally around 13 feet. .FRIDAY...South winds 15 to 25 knots becoming southwest to 30 knots. Snow showers in the morning, then rain and snow showers in the afternoon. Waves 2 feet or less building to 5 to 8 feet. Waves occasionally around 10 feet. .FRIDAY NIGHT...Southwest winds to 30 knots becoming west and increasing to 40 knot gales overnight. Rain showers with snow showers likely. Waves 7 to 10 feet building to 16 to 21 feet. Waves occasionally around 27 feet. .SATURDAY...West gales to 40 knots becoming north and diminishing to 5 to 10 knots. Snow showers likely during the day. Waves 16 to 21 feet subsiding to 2 to 4 feet. Waves occasionally around 27 feet. .SUNDAY...East winds 15 to 25 knots becoming southeast and increasing to 40 knot gales. Snow showers likely during the day, then a chance of rain and snow showers likely Sunday night. Waves 2 to 4 feet building to 9 to 12 feet. Waves occasionally around 15 feet. .MONDAY...South gales to 40 knots becoming west. Rain and snow showers. Waves 9 to 12 feet building to 15 to 19 feet. Waves occasionally around 24 feet. $$ LOZ061-122115- MAFOR 1215/ ONTARIO WEST 1/2 11640 11630 11730 11720 11610 11500 11410 11337. Waves 6 to 10 feet subsiding to 5 to 8 feet, and occasionally around 13 feet this afternoon. Waves 4 to 7 feet subsiding to 1 to 3 feet, and occasionally around 9 feet tonight. Waves 1 to 3 feet building to 3 to 5 feet Friday morning. ONTARIO EAST 1/2 12640 11740 11730 11720 11600 11510 11327. Waves 8 to 12 feet, and occasionally around 15 feet this afternoon. Waves 7 to 10 feet subsiding to 2 to 4 feet, and occasionally around 13 feet tonight. Waves 2 feet or less building to 2 to 4 feet Friday morning. $$