FZUS61 KBUF 191409 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1009 AM EDT Thu Mar 19 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...Following the passage of a warm front, a 30.2 inch high will build across the Great Lakes through this evening. A 29.8 inch low will track from the upper Great Lakes to the lower Great Lakes Friday, before a 30.0 inch high becomes briefly established Saturday. Another 29.6 inch wave of low pressure will cross the lower Great Lakes Sunday with a strong cold front in its wake. A 30.4 inch high is then forecast to build across the Great Lakes on Monday. LOZ062-192100- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1009 AM EDT Thu Mar 19 2026 .REST OF TODAY...Southwest winds around 10 knots becoming west. A chance of sprinkles and flurries late this morning, then a chance of sprinkles early this afternoon. Waves 1 to 2 feet. .TONIGHT...West winds 10 knots or less becoming southeast. Waves 1 foot or less. .FRIDAY...Southeast winds 5 to 15 knots becoming west. Rain showers with snow showers likely in the morning, then rain showers in the afternoon. Waves 1 to 3 feet. .FRIDAY NIGHT...North winds 5 to 10 knots becoming northwest. Rain showers in the evening. Waves around 1 foot. .SATURDAY...West winds 10 to 15 knots becoming northeast. A chance of rain and snow showers Saturday night. Waves 1 to 2 feet. .SUNDAY...Northeast winds 10 to 15 knots increasing to 15 to 25 knots. Rain and snow showers likely. Waves 2 to 4 feet building to 5 to 7 feet. Waves occasionally around 9 feet. .MONDAY...North winds 15 to 25 knots becoming northwest. Waves 4 to 7 feet subsiding to 2 to 3 feet. Waves occasionally around 9 feet. $$ LOZ063-064-192100- Lake Ontario open waters from Hamlin Beach to Mexico Bay- 1009 AM EDT Thu Mar 19 2026 .REST OF TODAY...Southwest winds 5 to 15 knots becoming west. A chance of sprinkles and flurries, then a chance of sprinkles late. Waves 1 to 3 feet. .TONIGHT...West winds 10 knots or less becoming southwest. Waves 2 feet or less. .FRIDAY...Southeast winds 5 to 15 knots becoming west. Rain showers with snow showers likely in the morning, then rain showers in the afternoon. Waves 1 to 2 feet building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY NIGHT...North winds 10 to 15 knots becoming northwest. Rain showers in the evening, then a chance of rain showers overnight. Waves 1 to 2 feet. .SATURDAY...Northwest winds 10 to 15 knots becoming northeast. A chance of rain showers Saturday night. Waves 1 to 3 feet. .SUNDAY...Northeast winds 10 to 15 knots increasing to 15 to 25 knots. Rain and snow showers likely. Waves 1 to 3 feet building to 5 to 8 feet. Waves occasionally around 10 feet. .MONDAY...North winds 15 to 25 knots becoming northwest. A chance of snow showers during the day. Waves 5 to 8 feet subsiding to 3 to 5 feet. Waves occasionally around 10 feet. $$ LOZ065-192100- Lake Ontario open waters from Mexico Bay to the Saint Lawrence River- 1009 AM EDT Thu Mar 19 2026 .REST OF TODAY...South winds 15 to 20 knots becoming southwest 10 to 15 knots. A chance of snow showers late this morning, then a chance of flurries and sprinkles this afternoon. Waves 2 to 4 feet subsiding to 1 to 3 feet. .TONIGHT...West winds 10 knots or less becoming south. Waves 2 feet or less. .FRIDAY...Southeast winds 5 to 15 knots becoming north. Snow showers likely in the morning, then rain showers in the afternoon. Waves 1 foot or less building to 2 to 4 feet, then subsiding to 1 to 3 feet. .FRIDAY NIGHT...North winds 5 to 10 knots. Rain showers in the evening, then a chance of snow showers overnight. Waves 1 foot or less. .SATURDAY...Northwest winds 10 to 15 knots becoming north. A chance of rain and snow showers Saturday night. Waves 1 to 3 feet. .SUNDAY...Northeast winds 10 to 15 knots increasing to 15 to 25 knots. Rain and snow showers likely. Waves 2 feet or less building to 3 to 5 feet. .MONDAY...North winds 15 to 25 knots. A chance of snow showers during the day. Waves 3 to 5 feet subsiding to 1 to 3 feet. $$ LOZ061-192100- MAFOR 1915/ ONTARIO WEST 1/2 11500 12600 12700 11600 11310 11327. Waves 2 feet or less this afternoon and tonight. Waves 1 to 3 feet Friday morning. ONTARIO EAST 1/2 12510 12600 11700 11600 11300 11320. A chance of rain and snow showers Friday morning. Waves 1 to 3 feet this afternoon. Waves 2 feet or less tonight. Waves 1 to 3 feet Friday morning. $$