Which is the hottest month in Thunder Bay?

The hottest time of year in Thunder Bay is normally July. Expect maximum daytime temperatures to reach 24°C.

Which month has the most rain in Thunder Bay?

In terms of rainfall, August is usually the wettest month in Thunder Bay with 88mm on average. There are normally 13 days in August with some rain.

When is it sunniest in Thunder Bay?

The sunniest time of year in Thunder Bay is normally July with bright sunshine on average for 61% of daylight hours; that's 10 hours of sunshine per day.

When is the sea warmest in Thunder Bay?

The sea is usually at its warmest in Thunder Bay in August when the water temperature reaches 13°C.

Best time to visit Thunder Bay

Q: When is the best time to visit Thunder Bay?

The best time to visit Thunder Bay is July based on the following average weather conditions. Maximum daytime temperature = 22 - 30°C. Daily hours of sunshine = 10 hours or more.

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Thunder Bay by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

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When is the best time to visit Thunder Bay?

The best time to visit Thunder Bay is July based on the following average weather conditions.

Maximum daytime temperature = 72 - 86°F [remove]
Daily hours of sunshine = 10 hours or more [remove]

Change the criteria to reflect your weather preferences.

0.5
Jan
1
Feb
1
Mar
1.5
Apr
2
May
4
Jun
5
Jul
4
Aug
1.5
Sep
0.5
Oct
0
Nov
0
Dec

Change criteria

Max Day Temperature (°F)

16
Jan
21
Feb
32
Mar
46
Apr
59
May
68
Jun
75
Jul
72
Aug
63
Sep
50
Oct
36
Nov
21
Dec

Hours of Sunshine (daily)

4
Jan
5
Feb
5
Mar
7
Apr
8
May
9
Jun
10
Jul
8
Aug
5
Sep
4
Oct
3
Nov
3
Dec

Best time to visit

Destination

Daytime temperature

Sunshine hours

Sea temperature

Monthly rainfall

Days with some rain

Heat & humidity

The weather guide for Ontario (Thunder Bay) shows long term weather averages processed from data supplied by CRU (University of East Anglia) & today's weather forecast provided by meteoblue. Find out more about our data sources.

Metric (°C) | Imperial (°F)