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Weather & Climate
Cornwall, Ontario, Canada
Overview
Climate data and monthly weather averages for Cornwall.
Key Metrics
Annual Avg
7°C
Summer Avg
20.1°C
Winter Avg
-7.2°C
Record High
36.9°C
Record Low
-34.6°C
Annual Precipitation
966.6 mm
Avg Humidity
82%
Summer Humidity
78%
Winter Humidity
90%
Monthly Averages
| Month | High (°C) | Avg (°C) | Low (°C) | Rain (mm) | Humidity (%) | Sunshine (h) | Wind (kph) |
|---|---|---|---|---|---|---|---|
| Jan | 14.3° | -9° | -34.1° | 55.2 | 91% | 45 | 42.3 |
| Feb | 16.8° | -7.8° | -34.6° | 51 | 90% | 68 | 43.2 |
| Mar | 25.5° | -1.9° | -28.1° | 59.2 | 83% | 113 | 40.4 |
| Apr | 28° | 5.9° | -11.4° | 82.5 | 77% | 136 | 37.3 |
| May | 32.6° | 13.3° | -3.8° | 88 | 77% | 166 | 29.6 |
| Jun | 33.8° | 18.4° | 1.7° | 110.1 | 79% | 174 | 23 |
| Jul | 36.9° | 21.3° | 7.5° | 98.9 | 78% | 183 | 19.3 |
| Aug | 35.5° | 20.6° | 7.3° | 86.2 | 76% | 159 | 21.9 |
| Sep | 33.9° | 16.7° | -0.1° | 87.6 | 76% | 119 | 28 |
| Oct | 27.3° | 9.2° | -5° | 104.2 | 80% | 73 | 26.2 |
| Nov | 21.9° | 2.3° | -20.8° | 69 | 84% | 44 | 31.8 |
| Dec | 18.3° | -4.9° | -29.8° | 74.7 | 90% | 32 | 39.2 |
Frequently Asked Questions
Sources: NASA POWER · Last updated: 2025
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