FZUS61 KBUF 300803 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 403 AM EDT Mon Mar 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...A frontal zone will stall near the lake tonight through Tuesday. A 29.6 inch low will then move across southern Ontario province Tuesday evening before reaching the Canadian Maritimes Wednesday, with a trailing cold front moving south across the lake. A 30.6 inch high will then build east across Ontario and Quebec Wednesday through Thursday. A 29.6 inch low is then forecast to move into the central Great Lakes Thursday night before reaching southern Quebec late Friday. LOZ062-301500- Lake Ontario open waters from the Niagara River to Hamlin Beach- 403 AM EDT Mon Mar 30 2026 .TODAY...Southwest winds 10 to 15 knots. Waves 1 foot or less building to 1 to 3 feet. .TONIGHT...Southwest winds 5 to 15 knots becoming east. A chance of showers late in the evening. Showers with a chance of thunderstorms after midnight. Waves 1 to 3 feet. .TUESDAY...East winds 10 to 15 knots becoming southeast 15 to 20 knots. Rain showers with a chance of thunderstorms. Waves 1 to 3 feet building to 2 to 4 feet. .TUESDAY NIGHT...South winds 15 to 20 knots becoming west. Showers with a chance of thunderstorms. Waves 2 to 4 feet building to 3 to 6 feet. .WEDNESDAY...Northwest winds 15 to 25 knots becoming northeast. Rain showers likely during the day, then a chance of rain and snow showers Wednesday night. Waves 3 to 5 feet building to 3 to 6 feet. .THURSDAY...East winds to 30 knots becoming southeast. Rain and snow showers during the day, then rain showers Thursday night. Waves 5 to 9 feet. Waves occasionally around 11 feet. .FRIDAY...South winds 15 to 25 knots becoming north and diminishing to 10 to 15 knots. Showers during the day, then a chance of showers Friday night. Waves 3 to 6 feet subsiding to 2 to 4 feet. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-301500- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 403 AM EDT Mon Mar 30 2026 .TODAY...South winds 10 to 15 knots becoming southwest. Waves 1 to 3 feet. .TONIGHT...Southwest winds 5 to 10 knots becoming northeast. A chance of rain showers late in the evening. Rain showers after midnight, then rain showers with a chance of thunderstorms late. Waves 1 to 3 feet. .TUESDAY...Northeast winds 5 to 15 knots becoming east. Rain showers with a chance of thunderstorms. Waves 2 feet or less. .TUESDAY NIGHT...South winds 10 to 15 knots becoming west 15 to 20 knots. Rain showers with a chance of thunderstorms. Waves 2 feet or less building to 3 to 6 feet. .WEDNESDAY...West winds 15 to 20 knots becoming northeast. Rain showers during the day, then a chance of rain and snow showers Wednesday night. Waves 3 to 6 feet subsiding to 3 to 5 feet. .THURSDAY...Northeast winds 15 to 25 knots becoming southeast. Rain and snow showers during the day, then rain showers Thursday night. Waves 4 to 7 feet. Waves occasionally around 9 feet. .FRIDAY...South winds 15 to 25 knots becoming north. Rain showers. Waves 3 to 6 feet subsiding to 2 to 4 feet. Winds and waves higher in and near thunderstorms. $$ LOZ061-301500- MAFOR 3009/ ONTARIO WEST 1/2 11500 14510 11600 12206. A chance of thunderstorms overnight. Waves 1 to 3 feet. ONTARIO EAST 1/2 11410 13510 11500 11600 11100 11106. Waves 1 to 3 feet. $$