Weather in Thunder Bay: April
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Average day temperature: | 37.5°F |
| Average night temperature: | 30.9°F | |
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Sea water temperature: | 34.5°F |
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Number of sunny days: | 5 days |
| Day length: | 12.9 - 14.5 hours | |
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Number of days with precipitation: | 3 days |
| Precipitation totals: | 1.1 in. | |
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forecast
| Thunder Bay |
temperature
| Thunder Bay |
Air temperature in April, °F
The highest day temperature during April of 2026 was 59°F. At the same time the lowest night temperature was 7°F. Daily and nightly averages during April were 39.9°F and 30.1°F.
Sea water temperature in Thunder Bay in April, °F
The average sea water temperature in April of 2026 was 33.4°F. The highest and lowest sea temperatures during the month were 34.9°F and 32.7°F.
Mostly all days in April are cloudy but sunny and partly cloudy days are also possible.
Precipitation total in April, in.
Precipitation total value in Thunder Bay in April is 1.1 in. Other months of the year show relatively similar values.
The average wind speed value in April is 8.6 mph It makes April one of the most windy months of the year.
This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in April is: 4.9.
Best time for vacation in Thunder Bay
Thunder Bay on a weather map
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