FZUS61 KBUF 180210 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1009 PM EDT Fri Apr 17 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 30.0 inch high over the Lake this evening will slide east into New England tonight. Meanwhile, a 29.4 inch low near Lake Superior this evening will move to James Bay and deepen to 29.0 inches Saturday, while pushing a trailing strong cold front across the Lake later Saturday and Saturday evening. A 30.4 inch high will then settle southeastward across the Great Lakes Sunday through Monday night, before sliding off the mid-Atlantic coast Tuesday. A 29.4 inch low over lower Hudson Bay Tuesday, will weaken to 29.9 inches by Wednesday, while pushing an attendant weak cold front across the Lake Tuesday night. A 30.2 inch high will then build across the Great Lakes region Wednesday and Thursday. LOZ062-180900- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1009 PM EDT Fri Apr 17 2026 .OVERNIGHT...East winds 5 to 15 knots. Patchy fog. Waves 2 feet or less. .SATURDAY...Southeast winds 10 to 15 knots becoming southwest 15 to 20 knots. Patchy fog early. A chance of showers late in the morning. Showers in the afternoon. Waves 1 to 3 feet. .SATURDAY NIGHT...West winds 15 to 20 knots diminishing to 10 to 15 knots. Rain showers likely. Waves 2 to 4 feet. .SUNDAY...West winds 10 to 15 knots increasing to 15 to 20 knots. A chance of rain showers. Waves 2 to 4 feet building to 3 to 5 feet. .SUNDAY NIGHT...West winds 15 to 20 knots becoming northwest. A chance of rain showers in the evening. Waves 3 to 5 feet. .MONDAY...Northwest winds 15 to 20 knots becoming southwest 5 to 15 knots. Waves 2 to 4 feet subsiding to 1 to 3 feet. .TUESDAY...South winds 10 to 15 knots becoming northwest. A chance of rain showers. Waves 1 to 3 feet. .WEDNESDAY...North winds 5 to 15 knots becoming northeast. Waves 2 feet or less. $$ LOZ063>065-180900- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1009 PM EDT Fri Apr 17 2026 .OVERNIGHT...Southeast winds 10 knots or less increasing to 10 to 15 knots. Patchy fog. Waves 2 feet or less. .SATURDAY...Southeast winds 15 to 25 knots becoming south. Patchy fog early. A chance of showers early in the afternoon. Showers late. Waves 1 to 3 feet building to 3 to 5 feet. .SATURDAY NIGHT...Southwest winds 15 to 25 knots becoming west. Rain showers. Waves 3 to 5 feet. .SUNDAY...West winds 10 to 15 knots increasing to 15 to 20 knots. Rain showers in the morning, then a chance of rain showers in the afternoon. Waves 2 to 4 feet building to 3 to 6 feet. .SUNDAY NIGHT...West winds 15 to 20 knots becoming northwest. Waves 4 to 7 feet subsiding to 3 to 6 feet. Waves occasionally around 9 feet. .MONDAY...Northwest winds 15 to 20 knots becoming west 10 to 15 knots. Waves 3 to 5 feet subsiding to 1 to 3 feet. .TUESDAY...South winds 15 to 20 knots becoming west 10 to 15 knots. A chance of rain showers. Waves 1 to 3 feet. .WEDNESDAY...Northwest winds 5 to 15 knots becoming north. Waves 1 to 3 feet subsiding to 1 foot or less. $$ LOZ061-180900- MAFOR 1803/ ONTARIO WEST 1/2 12200 12310 11420 11426 11520 11620. Waves 2 feet or less overnight. Waves 1 to 3 feet building to 2 to 4 feet Saturday. Waves 2 to 4 feet Saturday evening. ONTARIO EAST 1/2 12300 12320 11420 11430 11436 11526. Waves 2 feet or less overnight. Waves 1 to 3 feet building to 3 to 5 feet Saturday. Waves 3 to 5 feet Saturday evening. $$