South Simcoe Forecast for Thursday May 9 New Tecumseth, ON, Canada / FM92 South Simcoe Today Adrianne Proceviat May 9, 2024 | 6:28 AM anizza / Depositphotos.com Foggy Start to the Day! Mainly cloudy today… High 16. Mainly cloudy this evening… Low 7. Remaining cloudy tomorrow… Slight chance of showers… High 17.