FZUS61 KBUF 230804 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 404 AM EDT Mon Mar 23 2026 SLZ022-024-231500- Saint Lawrence River from Cape Vincent to Saint Regis 404 AM EDT Mon Mar 23 2026 .TODAY...Northeast winds 5 to 10 knots becoming north. Mostly cloudy. .TONIGHT...Northwest winds 10 knots or less. Mostly cloudy early, then clearing. .TUESDAY...West winds 10 knots or less becoming southwest 10 to 15 knots. Sunny in the morning, then becoming partly sunny. .TUESDAY NIGHT...Southwest winds 5 to 15 knots. Mostly cloudy. .WEDNESDAY...Southwest winds 5 to 10 knots. A chance of rain and snow showers during the day, then rain and snow showers likely Wednesday night. .THURSDAY...Southwest winds 5 to 10 knots becoming northwest. Rain showers likely with a chance of snow showers during the day, then rain and snow showers likely Thursday night. .FRIDAY...North winds 5 to 10 knots becoming northwest. A chance of rain and snow showers during the day. $$