Measurements:
°C
°F
CURRENT WEATHER
07:50
Thunder Bay
40°F
SE 8 mph
Feels like: 34°F
Precip: 0%
World Resorts Canada Thunder Bay Weather

7 Day Weather Forecast

05.19
tue
DAY
38°F
SE 11 mph
precip
0%
NIGHT
32°F
SE 7 mph
precip
0%
05.20
wed
DAY
46°F
SE 6 mph
precip
0%
NIGHT
32°F
N 2 mph
precip
0%
05.21
thu
DAY
54°F
N 7 mph
precip
0%
NIGHT
40°F
NE 2 mph
precip
0%
05.22
fri
DAY
52°F
NW 7 mph
precip
0%
NIGHT
38°F
W 6 mph
precip
0%
05.23
sat
DAY
42°F
W 7 mph
precip
100%
NIGHT
40°F
W 6 mph
precip
100%
05.24
sun
DAY
50°F
NW 2 mph
precip
27%
NIGHT
44°F
NW 4 mph
precip
44%
05.25
mon
DAY
56°F
N 6 mph
precip
30%
NIGHT
52°F
NW 3 mph
precip
100%

Thunder Bay Sea Water Temperature in May, °F

Select Year: 2026 2025 2024

The average sea surface temperature in May 2026 for Thunder Bay was 2.5°F. The maximum and minimum values were 1.1°F and 4.9°F respectively.

Thunder Bay on the Weather Map

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:
January 9.8 °F
February 11.1 °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 8 mph
more details