Forecast for Alliston for July 24th:
| Today | Mainly sunny. Wind becoming southwest 30 km/h gusting to 50 this morning. High 34. Humidex 41. UV index 9 or very high. |
| Tonight | Cloudy with 70 percent chance of showers and risk of a thunderstorm. Wind northwest 30 km/h gusting to 50 becoming light this evening. Low 21. |
| Fri, 25 Jul | Mainly cloudy. 40 percent chance of showers early in the morning. High 26. Humidex 34. UV index 6 or high. |
| Night | Cloudy periods. Low 16. |
