FZUS61 KBUF 272003 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 403 PM EDT Mon Apr 27 2026 SLZ022-024-280300- Saint Lawrence River from Cape Vincent to Saint Regis 403 PM EDT Mon Apr 27 2026 .TONIGHT...East winds 10 knots or less becoming south. Mainly clear this evening, then becoming partly cloudy. .TUESDAY...South winds 10 to 15 knots. A chance of showers in the afternoon. .TUESDAY NIGHT...South winds 5 to 15 knots becoming southwest. A chance of showers. .WEDNESDAY...Southwest winds less than 10 knots becoming east. Showers likely in the afternoon. .WEDNESDAY NIGHT...Northeast winds 10 knots or less becoming southwest. Showers. .THURSDAY...Southwest winds 5 to 10 knots becoming west. Rain showers during the day, then a chance of rain showers Thursday night. .FRIDAY...West winds 5 to 15 knots diminishing to less than 10 knots. A chance of rain showers. .SATURDAY...West winds 10 knots or less. A chance of rain and snow showers during the day, then a chance of rain showers Saturday night. $$