South Simcoe Forecast for Tuesday April 30 New Tecumseth, ON, Canada / FM92 South Simcoe Today Adrianne Proceviat Apr 30, 2024 | 6:33 AM Diamond T Design Scattered showers this morning, ending near noon today… Cloudy this afternoon… High 18. Cloudy with fog patches developing this evening… Low 8. A mix of sun and cloud tomorrow… High 20.