26.08
wed
wed
Day
70°F
SE 9 mph
Precip.
24%
24%
Night
61°F
SE 11 mph
Precip.
32%
32%
27.08
thu
thu
Day
61°F
SE 2 mph
Precip.
15%
15%
Night
55°F
S 7 mph
Precip.
12%
12%
28.08
fri
fri
Day
59°F
N 6 mph
Precip.
3%
3%
Night
55°F
NE 6 mph
Precip.
22%
22%
29.08
sat
sat
Day
59°F
NW 6 mph
Precip.
15%
15%
Night
59°F
SW 8 mph
Precip.
29%
29%
30.08
sun
sun
Day
57°F
W 13 mph
Precip.
19%
19%
Night
61°F
SW 8 mph
Precip.
33%
33%
31.08
mon
mon
Day
59°F
SW 10 mph
Precip.
44%
44%
Night
61°F
W 3 mph
Precip.
53%
53%
01.09
tue
tue
Day
66°F
E 11 mph
Precip.
24%
24%
Night
59°F
S 9 mph
Precip.
27%
27%
02.09
wed
wed
Day
59°F
SW 5 mph
Precip.
23%
23%
Night
59°F
W 4 mph
Precip.
32%
32%
03.09
thu
thu
Day
59°F
W 9 mph
Precip.
27%
27%
Night
59°F
SW 7 mph
Precip.
25%
25%
04.09
fri
fri
Day
63°F
NW 7 mph
Precip.
13%
13%
Night
61°F
NW 4 mph
Precip.
47%
47%
05.09
sat
sat
Day
63°F
NE 9 mph
Precip.
9%
9%
Night
63°F
E 5 mph
Precip.
7%
7%
06.09
sun
sun
Day
63°F
W 3 mph
Precip.
8%
8%
Night
61°F
N 6 mph
Precip.
27%
27%
07.09
mon
mon
Day
61°F
W 3 mph
Precip.
24%
24%
Night
61°F
SE 12 mph
Precip.
12%
12%
08.09
tue
tue
Day
55°F
W 2 mph
Precip.
19%
19%
Night
57°F
N 3 mph
Precip.
22%
22%
sea water
temperature
temperature
| Thunder Bay |
monthly
weather
weather
| Thunder Bay |
current
weather
weather
| Thunder Bay |
7 days
forecast
forecast
| Thunder Bay |
Sea water temperature in August, °F
Show year:
2026
2025
2024
The average sea water temperature in August of 2026 was 61.1°F. The highest and lowest sea temperatures during the month were 63.7°F and 56.3°F.
Sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 59.9°F. The highest and lowest sea temperatures during the month were 62.2°F and 57.4°F.
Air temperature in Thunder Bay, °F
Precipitation total in Thunder Bay, in.
* Charts above show average data for the last 3 years.
Best time for vacation in Thunder Bay
Thunder Bay on a weather map
Places in Canada:
Name
°F
24 Hours Forecast
Thunder Bay
Local time: 12:21
August 26, wednesday
1500
73°F
SE
11 mph
11 mph
1800
68°F
SE
11 mph
11 mph
2100
66°F
SE
11 mph
11 mph
August 27, thursday
0000
61°F
SE
11 mph
11 mph
0300
57°F
SE
9 mph
9 mph
0600
55°F
SE
8 mph
8 mph
0900
54°F
SE
6 mph
6 mph
1200
61°F
SE
2 mph
2 mph
