forecast
detailed forecast
| Extented weather forecast for Cornwall Ontario and the Seaway Issued by Environment Canada at 1530 ET Thu Sep 17 2026 |
| Tonight: Cloudy with 30 percent chance of showers early this evening. Clearing this evening. Low 11. Friday: Mainly sunny. Wind becoming north 20 km/h gusting to 40 in the morning. High 19. Uv index 5 or moderate. Friday Night: Clear. Low plus 5. Saturday: A mix of sun and cloud. High 18. Saturday Night: Cloudy. Low 9. Sunday: Cloudy. High 20. Sunday Night: Clear. Low 6. Monday: Sunny. High 17. Monday Night: Clear. Low plus 5. Tuesday: Sunny. High 18. Tuesday Night: Clear. Low 8. Wednesday: Sunny. High 19. |
regional radar

■ Cornwall
Rain Snow Ice Mix













