FZUS61 KBUF 252002 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 402 PM EDT Sat Apr 25 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 30.3 inch high will build across the lower Great Lakes tonight through Monday. A 29.4 inch low over the Great Plains Monday night will advance northeast into the upper Great Lakes later Monday night into Tuesday morning, while pushing a warm front across the lake. The low will head northeast to James Bay Tuesday night sending a cold front across the lake. An inverted trough averaging 29.7 inch inverted trough is expected across the lower Great Lakes Wednesday through Wednesday night. LOZ062-260300- Lake Ontario open waters from the Niagara River to Hamlin Beach- 402 PM EDT Sat Apr 25 2026 .TONIGHT...Northeast winds to 30 knots diminishing to 10 to 15 knots. Rain showers likely early. Waves 6 to 10 feet subsiding to 3 to 5 feet. Waves occasionally around 13 feet. .SUNDAY...Northeast winds 5 to 10 knots becoming east. Waves 1 to 3 feet subsiding to 1 foot or less. .SUNDAY NIGHT...East winds 10 knots or less. Waves 1 foot or less. .MONDAY...East winds 10 knots or less increasing to 10 to 15 knots. Waves 2 feet or less. .MONDAY NIGHT...East winds 15 to 20 knots becoming southeast 10 to 15 knots. Waves 1 to 3 feet. .TUESDAY...Southeast winds 15 to 20 knots becoming southwest and diminishing to 5 to 10 knots. Showers. Waves 2 to 4 feet subsiding to 1 to 3 feet. .WEDNESDAY...West winds 5 to 15 knots. A chance of showers. Waves 2 feet or less building to 2 to 3 feet. .THURSDAY...West winds 10 to 15 knots becoming northwest. Waves 1 to 3 feet. $$ LOZ063>065-260300- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 402 PM EDT Sat Apr 25 2026 .TONIGHT...East winds 15 to 25 knots diminishing to 5 to 15 knots. Rain showers this evening. Waves 4 to 7 feet subsiding to 1 to 3 feet. Waves occasionally around 9 feet. .SUNDAY...Northeast winds 10 knots or less becoming northwest. Waves 2 feet or less. .SUNDAY NIGHT...Northwest winds less than 10 knots. Waves 1 foot or less. .MONDAY...Southeast winds 10 knots or less becoming northeast. Waves 1 foot or less. .MONDAY NIGHT...East winds 5 to 15 knots becoming southeast 15 to 20 knots. Waves 1 to 3 feet. .TUESDAY...Southeast winds 15 to 20 knots becoming south. Showers. Waves 2 to 4 feet building to 3 to 5 feet, then subsiding to 2 to 4 feet. .WEDNESDAY...South winds 10 to 15 knots becoming west. Showers likely. Waves 1 to 3 feet. .THURSDAY...West winds 15 to 20 knots becoming northwest. Waves 2 to 4 feet. $$ LOZ061-260300- MAFOR 2521/ ONTARIO WEST 1/2 11146 11130 11220 11110 12100 11200 11100. Waves 6 to 10 feet subsiding to 3 to 5 feet, and occasionally around 13 feet tonight. Waves 1 to 3 feet subsiding to 1 foot or less Sunday. ONTARIO EAST 1/2 11236 11220 11210 11200 12100 11800 11700. Waves 3 to 6 feet subsiding to 2 feet or less tonight. Waves 1 foot or less Sunday. $$