The temperatures in Oshawa in September are comfortable with low of 14°C and and high up to 21°C.
You can expect about 3 to 8 days of rain in Oshawa during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Oshawa in September 2025.
If you’re planning to visit Oshawa in the near future, we highly recommend that you review the 14 day weather forecast for Oshawa before you arrive.
Temperatures
21° / 14°
Rainy Days
6
Snowy Days
0
Dry Days
24
Rainfall
117
mm
Sun Hours
10.6
Hrs
