


Great Lakes Forecast
Issued by NWS
Issued by NWS
853 FZUS61 KBUF 010202 GLFLO Open Lake Forecast for Lake Ontario National Weather Service Buffalo NY 1002 PM EDT Mon Jun 30 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 29.6 inch low will move from northwest Ontario province today to east of Hudson Bay Tuesday while deepening to 29.2 inches. A cold front trailing this low will cross the lake Tuesday morning. A 29.9 inch high will build into the Upper Great Lakes Wednesday and Thursday. The high will then strengthen to 30.1 inches as it centers over the lake on Friday. LOZ062-010900- Lake Ontario open waters from the Niagara River to Hamlin Beach- 1002 PM EDT Mon Jun 30 2025 .OVERNIGHT...South winds 5 to 10 knots becoming southwest. Showers likely with a chance of thunderstorms, then a chance of showers late. Waves 2 feet or less. .TUESDAY...Southwest winds 10 to 15 knots becoming west. Waves 1 to 2 feet. .TUESDAY NIGHT...West winds around 10 knots. Waves 1 to 2 feet. .WEDNESDAY...West winds around 10 knots becoming southwest. Waves 1 to 2 feet. .WEDNESDAY NIGHT...Southwest winds around 10 knots becoming west. A chance of showers and thunderstorms overnight. Waves 1 to 2 feet. .THURSDAY...West winds 5 to 10 knots becoming northwest. A chance of showers and thunderstorms during the day. Waves 1 to 2 feet. .FRIDAY...North winds 5 to 10 knots becoming southwest. Waves 1 foot or less. .SATURDAY...Southwest winds 5 to 15 knots. A chance of showers Saturday night. Waves 2 feet or less. Winds and waves higher in and near thunderstorms. $$ LOZ063>065-010900- Lake Ontario open waters from Hamlin Beach to the Saint Lawrence River- 1002 PM EDT Mon Jun 30 2025 .OVERNIGHT...South winds 5 to 15 knots. Showers likely with a chance of thunderstorms. Waves 2 feet or less. .TUESDAY...Southwest winds 10 to 15 knots becoming west. A chance of showers early. Waves 1 to 3 feet. .TUESDAY NIGHT...West winds 10 to 15 knots. Waves 1 to 3 feet. .WEDNESDAY...West winds 10 to 15 knots. Waves 1 to 2 feet. .WEDNESDAY NIGHT...Southwest winds 10 to 15 knots becoming west. A chance of showers and thunderstorms overnight. Waves 1 to 2 feet. .THURSDAY...West winds 5 to 15 knots becoming northwest. A chance of showers and thunderstorms during the day. Waves 1 to 2 feet. .FRIDAY...Northwest winds 5 to 10 knots becoming south. Waves 1 foot or less. .SATURDAY...South winds 5 to 15 knots. A chance of showers Saturday night. Waves 1 foot or less building to 1 to 3 feet. Winds and waves higher in and near thunderstorms. $$ LOZ061-010900- MAFOR 0103/ ONTARIO WEST 1/2 11400 13500 13610 11600. A chance of thunderstorms late this evening, then a chance of showers and thunderstorms overnight. Waves 1 to 2 feet. ONTARIO EAST 1/2 11400 11410 12510 14610. A chance of showers and thunderstorms overnight. A chance of showers Tuesday morning. Waves 2 feet or less overnight. Waves 1 to 3 feet Tuesday and Tuesday evening. $$