FZUS61 KBUF 221402 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1002 AM EDT Sat Aug 22 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 high pressure ridge averaging 30.1 inches exits toward the Canadian Maritimes today. Elsewhere, a 29.6 inch low should wobble northeastward from the central Great Lakes to southwestern Quebec through Monday. In response to the low's track, a warm front drifts northeastward across Lake Ontario tonight and then a cold front sweeps eastward across the lake overnight tonight through Sunday. Behind the cold front, a trough averaging 29.8 inches lingers over Lake Ontario through Monday. On Tuesday through Wednesday, a ridge averaging 30.1 inches builds from the western and central Great Lakes. The ridge should begin to exit eastward on Thursday and allow a warm front to sweep northeastward across Lake Ontario. LOZ062-222100- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1002 AM EDT Sat Aug 22 2026 .THIS AFTERNOON...Southeast winds 5 to 10 knots becoming east. A chance of showers and thunderstorms late. Waves around 1 foot. .TONIGHT...Southeast winds 5 to 15 knots becoming southwest. Showers with a chance of thunderstorms through the early overnight, then showers likely late. A chance of waterspouts after midnight. Waves 1 to 2 feet. .SUNDAY...West winds 15 to 25 knots. A chance of waterspouts. Showers likely in the morning, then showers likely with a chance of thunderstorms in the afternoon. Waves 1 to 3 feet building to 3 to 6 feet. .SUNDAY NIGHT...West winds 15 to 25 knots. A chance of waterspouts. A chance of showers and thunderstorms in the evening, then showers likely overnight. Waves 4 to 6 feet. .MONDAY...West winds 15 to 25 knots. A chance of waterspouts. Showers during the day, then a chance of showers Monday night. Waves 5 to 8 feet subsiding to 3 to 5 feet. Waves occasionally around 10 feet. .TUESDAY...West winds 15 to 20 knots diminishing to less than 10 knots. A chance of waterspouts during the day. A chance of showers during the day. Waves 2 to 4 feet subsiding to 1 foot or less. .WEDNESDAY...Southwest winds 10 knots or less becoming south. Waves 1 foot or less. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-222100- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1002 AM EDT Sat Aug 22 2026 .THIS AFTERNOON...Southeast winds 5 to 15 knots. Waves 1 to 3 feet subsiding to 1 foot or less. .TONIGHT...Southeast winds 10 to 15 knots becoming south and increasing to 15 to 25 knots. Showers likely with a chance of thunderstorms. A chance of waterspouts after midnight. Waves 1 to 3 feet building to 3 to 5 feet. .SUNDAY...South winds 15 to 25 knots becoming west. A chance of waterspouts. Showers with a chance of thunderstorms. Waves 3 to 5 feet building to 3 to 6 feet. .SUNDAY NIGHT...West winds 15 to 25 knots becoming southwest. A chance of waterspouts. Showers likely with a chance of thunderstorms in the evening, then showers overnight. Waves 3 to 6 feet building to 4 to 7 feet. Waves occasionally around 9 feet. .MONDAY...Southwest winds to 30 knots becoming west 15 to 25 knots. A chance of waterspouts. Showers. Waves 4 to 7 feet building to 6 to 9 feet, then subsiding to 4 to 7 feet. Waves occasionally around 11 feet. .TUESDAY...West winds 15 to 20 knots diminishing to 5 to 15 knots. A chance of waterspouts during the day. Showers likely during the day, then a chance of showers Tuesday night. Waves 3 to 6 feet subsiding to 1 to 3 feet. .WEDNESDAY...West winds 5 to 15 knots becoming south. Waves 2 feet or less. Winds and waves higher in and near thunderstorms. $$ LOZ061-222100- MAFOR 2215/ ONTARIO WEST 1/2 11300 12200 11406 12416 11516 11626. A chance of waterspouts overnight and Sunday morning. A chance of thunderstorms this evening. Waves 1 to 3 feet this afternoon and tonight. Waves 1 to 3 feet building to 2 to 4 feet Sunday morning. ONTARIO EAST 1/2 11310 11300 11310 11410 11420 12436 11426. A chance of waterspouts overnight and Sunday morning. A chance of thunderstorms this evening. Waves 2 feet or less this afternoon. Waves 1 to 3 feet building to 3 to 5 feet tonight. Waves 3 to 5 feet subsiding to 2 to 4 feet Sunday morning. $$