Measurements:
°C
°F
Thunder Bay
-6°F
SE 6 mph
Feels like: -20°F
Precip: 0%
World Resorts Canada Thunder Bay Weather April Weather in Thunder Bay

Thunder Bay Weather: April

Average Day Temperature: 35.7°F
Average Night Temperature: 28.9°F
Sea Water Temperature: 32.9°F
Number of Sunny Days: 4 days
Sunshine Hours: 12.9 - 14.5 hours
Number of Rainy Days: 2 days
Precipitation Totals: 1.1 in
Number of Snowy Days: 1 day

Air Temperature in April, °F

Select Year: 2025 2024 2023

The highest day temperature in April 2025 was 52°F. The lowest night temperature was 13°F. The average values for day and night temperatures during April were 38.0°F и 29.1°F respectivly.

Thunder Bay Water Sea Temperature in April, °F

Select Year: 2025 2024 2023

The average sea surface temperature in April 2025 for Thunder Bay was 32.7°F. The maximum and minimum values were 30.8°F and 37.2°F respectively.

Sunny, Cloudy and Gloomy days

Most of the days in April are gloomy but you can also expect sunny days.

Precipitation Totals in April, in

Precipitation total in April for Thunder Bay is 1.1 in. It makes april the most rainy month of the year.

Wind Speed in April, mph

The average wind speed in April is 8.8 mph. It makes April one of the most windy months of the year for Thunder Bay.

Average Sunny Hours Per Day

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Thunder Bay in April is 4.5 hours.

Best Time to Visit Thunder Bay
The most sunny months:
September 14 days
August 14 days
July 12 days
The most warm months:
July 71.5 °F
August 71.2 °F
June 64.4 °F
Warmest sea temperature:
August 64.9 °F
September 61.3 °F
July 60.6 °F
The most cold months:
February 10.3 °F
January 10.9 °F
December 17.9 °F
The most rainy months:
September 2 days
August 2 days
April 2 days
The most windy months:
November 9 mph
December 9 mph
April 9 mph

Thunder Bay on the Weather Map

Canada Resorts:
NAME
Halifax +30
Kingston +30
Montreal +32
Niagara Falls +30
Ottawa +26
Prince Edward Island +26
Quebec +20
Saint John +28
St. John's +26
Sydney +26
Toronto +28
Vancouver +44
Victoria +46
Winnipeg +4
Yellowknife -12
24 Hours Weather Forecast
Thunder Bay
Local time: 09:32
11 jan, sunday
1200 4°F
SE
5 mph
1500 14°F
NE
6 mph
1800 20°F
NE
6 mph
2100 22°F
NE
9 mph
12 jan, monday
0000 22°F
NE
9 mph
0300 20°F
E
9 mph
0600 18°F
E
8 mph
0900 22°F
E
8 mph