The Durham weather forecast for Tuesday, October 13 calls for an unusually warm day with morning rain and a risk of thunderstorms before cooler air arrives overnight.
Environment Canada’s 5 a.m. forecast for Oshawa says showers will begin early Tuesday morning and end near noon. There is then a 40 per cent chance of additional showers late in the afternoon, with a risk of a thunderstorm through the day.
The federal forecaster expects local rainfall amounts of 10 to 20 millimetres. Southwest winds are forecast to reach 20 km/h late in the morning.
Temperature could reach 23 C
The daytime high is forecast to reach 23 C, about 10 degrees above the normal October 13 maximum of 13 C listed by Environment Canada for Oshawa. Humidity will make it feel warmer, with a humidex value of 30 expected.
Conditions were already mild and damp before sunrise. At 5 a.m., the Oshawa Executive Airport reported mist, calm winds, a temperature and dew point of 15.2 C, 100 per cent humidity and visibility of five kilometres.
A regional weather report published by INsauga on Monday afternoon also flagged the return of summer-like warmth and thunderstorm potential across southern Ontario. The current Environment Canada forecast provides the Durham-specific details residents should use for local planning.
Showers may continue into Tuesday evening
Tuesday night is expected to be partly cloudy. A 40 per cent chance of showers remains early in the evening, along with a risk of a thunderstorm. Winds are forecast to shift to the northwest at 20 km/h later in the evening, with an overnight low of 13 C.
The change in wind direction will bring a sharp temperature drop Wednesday. Environment Canada forecasts a mix of sun and cloud, a high of 14 C and northwest winds of 20 km/h gusting to 40. Wednesday night is expected to become cloudy with a low of 7 C.
For Tuesday, drivers should be prepared for wet roads and reduced visibility in heavier showers. Residents with outdoor plans should continue checking the latest forecast because thunderstorm timing and rainfall amounts can change.
Sources
- Environment Canada’s Oshawa forecast, issued at 5 a.m. EDT on October 13, 2026.
- INsauga’s southern Ontario weather report, published October 12, 2026.
