FZUS61 KBUF 092003 GLFSL Forecast for the Saint Lawrence River including the Thousand Islands Region National Weather Service Buffalo NY 403 PM EDT Thu Jul 9 2026 SLZ022-024-100300- Saint Lawrence River from Cape Vincent to Saint Regis 403 PM EDT Thu Jul 9 2026 .TONIGHT...Light and variable winds. Showers with a chance of thunderstorms early, then a chance of showers and thunderstorms late this evening. .FRIDAY...Light and variable winds. Becoming mostly sunny. .FRIDAY NIGHT...North winds less than 10 knots. Mainly clear in the evening, then becoming partly cloudy. .SATURDAY...Northeast winds 10 knots or less becoming north. Sunny. .SATURDAY NIGHT...North winds less than 10 knots. Clear. .SUNDAY...Light and variable winds. Mainly clear. .MONDAY...Southwest winds 5 to 10 knots. Mainly clear, then becoming partly cloudy. .TUESDAY...Southwest winds 5 to 15 knots becoming west. A chance of showers Tuesday night. Winds and waves higher in and near thunderstorms. $$