FZUS61 KBUF 170804 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 403 AM 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 will build across the Lower Great Lakes today, and New England tonight. A 29.4 inch low near Lake Superior Friday 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 29.9 inch trough will move across the Lake Tuesday night before a 30.1 inch high moves across the Great Lakes region Wednesday. LOZ062-171500- Lake Ontario open waters from the Niagara River to Hamlin Beach- 404 AM EDT Fri Apr 17 2026 .TODAY...Northwest winds 10 knots or less becoming east. Areas of fog through early afternoon. Waves 1 foot or less. .TONIGHT...East winds 10 knots or less becoming southeast. Waves 1 foot or less. .SATURDAY...Southeast winds 10 to 15 knots becoming southwest 15 to 20 knots. A chance of showers in the morning, then showers in the afternoon. Waves 1 to 3 feet building to 2 to 4 feet. .SATURDAY NIGHT...West winds 15 to 20 knots becoming northwest. Rain showers in the evening, then rain showers likely overnight. Waves 3 to 5 feet. .SUNDAY...West winds 15 to 20 knots becoming northwest. A chance of rain showers. Waves 3 to 5 feet. .MONDAY...Northwest winds 15 to 20 knots becoming southwest 5 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. Waves 1 to 3 feet building to 2 to 4 feet. $$ LOZ063>065-171500- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 404 AM EDT Fri Apr 17 2026 .TODAY...North winds 5 to 10 knots becoming northwest. Areas of fog through early afternoon. Waves 2 feet or less. .TONIGHT...West winds 10 knots or less becoming southeast 10 to 15 knots. Waves 1 foot or less. .SATURDAY...Southeast winds 15 to 20 knots becoming south. Showers in the afternoon. Waves 1 to 3 feet building to 3 to 5 feet. .SATURDAY NIGHT...South winds 15 to 20 knots becoming west. Rain showers. Waves 3 to 5 feet. .SUNDAY...West winds 15 to 25 knots becoming northwest. Rain showers during the day. Waves 3 to 6 feet building to 4 to 7 feet. Waves occasionally around 9 feet. .MONDAY...Northwest winds 15 to 20 knots becoming west. Waves 3 to 6 feet subsiding to 2 to 4 feet. .TUESDAY...South winds 15 to 20 knots becoming southwest. A chance of rain showers Tuesday night. Waves 1 to 3 feet building to 2 to 4 feet. $$ LOZ061-171500- MAFOR 1709/ ONTARIO WEST 1/2 11703 11800 11100 14200 11300. Waves 1 foot or less. ONTARIO EAST 1/2 11703 12800 12700 13300. Waves 2 feet or less. $$