FZUS61 KBUF 210803 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 403 AM EDT Mon Sep 21 2026 SLZ022-024-211500- Saint Lawrence River from Cape Vincent to Saint Regis 403 AM EDT Mon Sep 21 2026 .TODAY...North winds 5 to 15 knots becoming northeast. Partly sunny. .TONIGHT...Northeast winds 5 to 10 knots. Partly to mostly cloudy. .TUESDAY...Northeast winds 5 to 10 knots. Sunny. .TUESDAY NIGHT...Northeast winds 5 to 10 knots. Mainly clear. .WEDNESDAY...Northeast winds 10 knots or less. Mainly clear. .THURSDAY...Northeast winds 10 knots or less. Mainly clear, then becoming partly cloudy. .FRIDAY...Northeast winds 5 to 10 knots becoming north. Partly cloudy. $$