Average Temperatures and Rainfall for Ontario

Average annual temperatures for Ontario (8°C/46°F) are slightly above the average for Canada (4°C/39°F).

Average annual rainfall for Ontario (891mm/35 inches) is significantly above the average for Canada (705mm/28 inches).

What is the warmest or hottest month in Ontario?

July is the hottest or warmest month in Ontario, with an average maximum temperate of 28°C/82°F.

What is the coldest or coolest month in Ontario?

January is the coolest or coldest month in Ontario, with an average minimum temperate of -9°C/16°F.

What is the most rainy or wettest month in Ontario?

June is the wettest or most rainy month in Ontario, with an average rainfall of 95mm/4 inches.

What is the least rainy or driest month in Ontario?

March is the driest or least rainy month in Ontario, with an average rainfall of 52mm/2 inches.

What is the warmest or hottest place in Ontario?

Amherstburg is the hottest or warmest place in Ontario, with an average maximum temperate of 11°C/52°F.

What is the coldest place in Ontario?

Thunder Bay is the coldest place in Ontario, with an average maximum temperate of 3°C/37°F.

What is the most rainy or wettest place in Ontario?

Fort Erie is the most rainy or wettest place in Ontario, with an average annual rainfall of 1,167mm/46 inches.

What is the least rainy or driest place in Ontario?

Greater Sudbury is the least rainy or driest place in Ontario, with an average annual rainfall of 184mm/7 inches.

Average Monthly Temperatures
Average Maximum Temperature Average Minimum Temperature
Average Monthly Rainfall
PlaceMin TempMax TempAvg TempRainfall
Ajax 5 13 9 938
Amherstburg 6 16 11 1,047
Barrie 4 12 8 768
Brampton 4 14 9 894
Burlington 4 14 9 771
Cambridge 4 14 9 771
Camlachie 6 14 10 975
Cornwall 1 13 7 864
Corunna 5 15 10 1,062
Fort Erie 5 14 10 1,167
Fort Frances -3 10 3 720
Greater Sudbury 0 10 5 184
Guelph 3 12 7 1,104
Hamilton 4 14 9 771
Kingston 3 12 8 1,056
Kitchener 3 12 7 1,104
Lambton Shores 6 14 10 975
London 4 14 9 1,106
Markham 4 14 9 894
Milton 4 14 9 771
Mississauga 6 14 10 831
Nepean 2 12 7 969
Niagara Falls 5 14 10 1,167
Niagara-on-the-Lake 5 14 10 886
Oakville 4 14 9 771
Oshawa 5 13 9 938
Ottawa 2 12 7 969
Petrolia 6 14 10 975
Port Colborne 5 14 10 886
Richmond Hill 4 14 9 894
Sarnia 6 14 10 975
Sault Ste. Marie 1 11 6 1,060
St. Catharines 5 14 10 886
Thorold 5 14 10 886
Thunder Bay -3 9 3 682
Toronto 4 14 9 894
Tottenham 2 12 7 852
Vaughan 4 14 9 894
Waterloo 3 12 7 1,104
Welland 5 14 10 886
Windsor 6 16 11 1,047