Great Lakes Forecast
Issued by NWS
Issued by NWS
479 FZUS61 KBUF 202003 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 403 PM EDT Mon Jul 20 2026 SLZ022-024-210300- Saint Lawrence River from Cape Vincent to Saint Regis 403 PM EDT Mon Jul 20 2026 .TONIGHT...Southwest winds 10 knots or less becoming south 10 to 15 knots. Partly to mostly cloudy. .TUESDAY...South winds 10 to 15 knots. A chance of showers late in the morning. Showers with thunderstorms likely in the afternoon. Some thunderstorms may produce gusty winds in the afternoon. .TUESDAY NIGHT...South winds 5 to 15 knots becoming southwest. Showers with a chance of thunderstorms in the evening, then showers overnight. .WEDNESDAY...Southwest winds 10 to 15 knots becoming west 15 to 20 knots. A chance of showers in the morning, then showers likely in the afternoon. .WEDNESDAY NIGHT...West winds 5 to 15 knots. Showers likely in the evening. .THURSDAY...Southwest winds 10 knots or less. Becoming mainly clear. .FRIDAY...Southwest winds less than 10 knots. Mainly clear, then becoming partly cloudy. .SATURDAY...Southwest winds less than 10 knots becoming south. Mainly clear, then becoming partly cloudy. Winds and waves higher in and near thunderstorms. $$