


Great Lakes Forecast
Issued by NWS
Issued by NWS
504 FZUS61 KBUF 172002 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 402 PM EDT Fri Oct 17 2025 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 slowly exit off to our east tonight and then off the eastern sea board Saturday. Meanwhile, a 29.1 inch surface low will track across northwestern across Ontario while pushing a warm front through the lakes. A developing 29.5 inch low over the Ohio Valley Saturday will strengthen to 29.3 inches as it moves northeast along a stationary boundary through the central Great Lakes Saturday night and Sunday. Another 29.5 inch low is then forecast to develop over the upper Ohio Valley Sunday night, then move east across the lower Great Lakes into western New England Monday, all while pushing a cold front across the lake. Surface high pressure builds northeast across the Ohio Valley and the Lower Lakes Monday, this as a 29.4 inch low tracks across Lake Superior through Tuesday. LOZ062-180300- Lake Ontario open waters from the Niagara River to Hamlin Beach- 402 PM EDT Fri Oct 17 2025 .TONIGHT...South winds 10 knots or less. Showers likely. Waves 1 foot or less. .SATURDAY...South winds 10 to 15 knots becoming southeast. A chance of showers early. Waves 2 feet or less. .SATURDAY NIGHT...Southeast winds 5 to 15 knots becoming south. A chance of showers. Waves 1 to 3 feet. .SUNDAY...South winds 15 to 25 knots. Showers. Waves 2 to 4 feet building to 3 to 6 feet. .SUNDAY NIGHT...South winds to 30 knots becoming west. Showers. Waves 5 to 8 feet building to 6 to 10 feet. Waves occasionally around 13 feet. .MONDAY...West winds to 30 knots becoming southwest and diminishing to 15 to 20 knots. Showers during the day, then a chance of showers Monday night. Waves 9 to 12 feet subsiding to 3 to 5 feet. Waves occasionally around 15 feet. .TUESDAY...South winds 15 to 20 knots becoming west and increasing to 30 knots. Showers. Waves 3 to 5 feet building to 6 to 9 feet. Waves occasionally around 11 feet. .WEDNESDAY...West winds to 30 knots diminishing to 15 to 25 knots. Showers likely. Waves 7 to 11 feet subsiding to 4 to 7 feet. Waves occasionally around 14 feet. $$ LOZ063>065-180300- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 402 PM EDT Fri Oct 17 2025 .TONIGHT...West winds 10 knots or less becoming south. A chance of showers this evening. A chance of showers late. Waves 1 foot or less. .SATURDAY...South winds 10 to 15 knots becoming southeast. A chance of showers in the morning. Waves 1 to 3 feet. .SATURDAY NIGHT...Southeast winds 15 to 25 knots becoming south. A chance of showers. Waves 1 to 3 feet building to 3 to 6 feet. .SUNDAY...Southeast winds 15 to 25 knots increasing to 30 knots. A chance of showers in the morning, then showers in the afternoon. Waves 5 to 8 feet. Waves occasionally around 10 feet. .SUNDAY NIGHT...South winds to 30 knots becoming southwest. Showers. Waves 5 to 9 feet building to 7 to 10 feet. Waves occasionally around 13 feet. .MONDAY...West winds to 30 knots becoming southwest 15 to 25 knots. Showers during the day, then a chance of showers Monday night. Waves 10 to 13 feet subsiding to 4 to 7 feet. Waves occasionally around 16 feet. .TUESDAY...South winds 15 to 25 knots becoming southwest to 30 knots. Showers. Waves 3 to 5 feet building to 6 to 10 feet. Waves occasionally around 13 feet. .WEDNESDAY...West winds to 30 knots diminishing to 15 to 25 knots. Showers. Waves 8 to 12 feet subsiding to 7 to 10 feet. Waves occasionally around 15 feet. $$ LOZ061-180300- MAFOR 1721/ ONTARIO WEST 1/2 11500 13400 13410 11310. A chance of showers tonight and Saturday morning. Waves 2 feet or less. ONTARIO EAST 1/2 11600 11500 12400 13410 11310. Waves 1 foot or less tonight. Waves 1 to 3 feet Saturday. $$