FZUS61 KBUF 302002 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 402 PM EDT Thu Apr 30 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...An elongated 29.7 inch low will gradually slide northeastward along the Atlantic Canada shoreline this evening. This low will then retrograde northward and then northwestward across the Canadian Maritimes and Quebec respectively Friday and Saturday. Another 29.7 inch low will then deepen to 29.2 inches as it tracks from the southeastern states northeast off the Atlantic coast Saturday through Sunday, while a 30.2 inch high ridges across the lower Great Lakes. A 29.1 inch low will then pinwheel counterclockwise about Ontario, Quebec, and Hudson Bay Monday through Tuesday night, sending an attendant cold front across the lake Tuesday. LOZ062-010300- Lake Ontario open waters from the Niagara River to Hamlin Beach- 402 PM EDT Thu Apr 30 2026 .TONIGHT...West winds 5 to 15 knots becoming northwest. Waves 1 to 2 feet. .FRIDAY...West winds 5 to 10 knots. Waves 1 foot or less. .FRIDAY NIGHT...West winds 5 to 10 knots becoming northwest. Waves 1 foot or less. .SATURDAY...Northwest winds 5 to 10 knots becoming west. Waves 1 foot or less. .SATURDAY NIGHT...West winds 5 to 10 knots becoming northwest. Waves around 1 foot. .SUNDAY...West winds 10 to 15 knots becoming southwest and increasing to 15 to 25 knots. A chance of rain showers Sunday night. Waves 1 to 2 feet building to 3 to 5 feet. .MONDAY...Southwest winds 15 to 25 knots increasing to 30 knots. A chance of showers. Waves 3 to 6 feet building to 5 to 8 feet. Waves occasionally around 10 feet. .TUESDAY...Southwest winds 15 to 25 knots becoming east and diminishing to 10 to 15 knots. A chance of showers. Waves 4 to 7 feet subsiding to 1 to 3 feet. Waves occasionally around 9 feet. $$ LOZ063>065-010300- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 402 PM EDT Thu Apr 30 2026 .TONIGHT...West winds 15 to 20 knots becoming northwest 5 to 15 knots. Waves 2 to 4 feet subsiding to 1 to 3 feet. .FRIDAY...Northwest winds 5 to 10 knots becoming west. Waves 2 feet or less. .FRIDAY NIGHT...West winds 5 to 10 knots. Waves 1 foot or less. .SATURDAY...West winds 5 to 15 knots. Waves 2 feet or less. .SATURDAY NIGHT...West winds 5 to 10 knots becoming northwest. Waves 1 to 2 feet. .SUNDAY...West winds 10 to 15 knots becoming southwest 15 to 20 knots. A chance of rain showers Sunday night. Waves 1 to 3 feet building to 2 to 4 feet. .MONDAY...Southwest winds 15 to 25 knots becoming south to 30 knots. A chance of showers. Waves 2 to 4 feet building to 4 to 7 feet. Waves occasionally around 9 feet. .TUESDAY...Southwest winds 15 to 25 knots becoming south and diminishing to 10 to 15 knots. A chance of showers. Waves 4 to 7 feet subsiding to 1 to 3 feet. Waves occasionally around 9 feet. $$ LOZ061-010300- MAFOR 3021/ ONTARIO WEST 1/2 11610 11710 12700 14600. Waves 1 to 3 feet tonight. Waves 1 foot or less Friday. ONTARIO EAST 1/2 11620 11610 11710 13700 12600. Waves 2 to 4 feet subsiding to 1 to 3 feet tonight. Waves 2 feet or less Friday. $$