Thunder Bay in september: average Weather, Temperature and Climate
Weather in Thunder Bay in september 2025
The weather in Thunder Bay in the month of september comes from statistical datas on the past years. You can view the weather statistics for the whole month, but also by using the tabs for the beginning, the middle and the end of the month.
Average weather throughout september
good weather 0.4cm
Weather at 6am
50°F
Clear/Sunny
34% of time
28%
17%
14%
Weather at 12pm
61°F
Clear/Sunny
42% of time
31%
15%
8%
Weather at 6pm
58°F
Clear/Sunny
42% of time
29%
18%
5%
Weather at 3am
52°F
36%
26%
13%
13%
Evolution of daily average temperature and precipitation in Thunder Bay in september
These charts show the evolution of average minimum/maximum temperatures as well as average daily precipitation volume in Thunder Bay in september.
The climate of Thunder Bay in september is good
The climate in september in Thunder Bay is quite dry (with 3.3in of rainfall over 5 days). This is better than the previous month since in august it receives an average of 3.5in of precipitation over 5 days.
The climate is quite cold here the month of september, but it is livable when dressing hot. Temperatures are up to 63°F. The seasonal minimum is 50°F. Thus, the mean temperature average on this month of september in Thunder Bay is 56°F. These temperatures are far removed from those records observed in Thunder Bay in the month of september with a maximum record of 81°F in 2012 and a minimum record of 29°F in 2018. You can hope to have about 12 days with temperatures above 65°F, or 40% of time.
On this month of september, day length in Thunder Bay is generally 12:35. Sunrise is at 06:34 and sunset is at 19:09.
With a good weather, september is a good time to go in this locality.
Seasonal average climate and temperature of Thunder Bay in september
Check below seasonal norms These statistics are compiled from the weather statements earlier years of the month of september.
| September | |||||
| Outside temperature | |||||
| Average temperature | 56°F | ||||
| Highest temperature | 63°F | ||||
| Lowest temperature | 50°F | ||||
| Highest record temperature | 81°F (2012) | ||||
| Lowest record temperature | 29°F (2018) | ||||
| Number of days at +65°F | 12 day(s) (40%) | ||||
| Number of days at -32°F | 0 day(s) (0%) | ||||
| Wind | |||||
| Wind speed | 17km/h | ||||
| Wind temperature | 47°F | ||||
| Precipitation (rainfall) | |||||
| Rainfall | 3.3in | ||||
| Number of days with rainfall | 5 day(s) (16%) | ||||
| Record daily rainfall | 2.2in (2019) | ||||
| Snowfall | 0.4cm | ||||
| Other climate data | |||||
| Humidity | 90% | ||||
| Visibility | 8.95km | ||||
| Cloud cover | 38% | ||||
| UV index | 4 | ||||
| Daily sunshine hours | 11 | ||||
| Sunrise and sunset | |||||
| Time of sunrise | 06:34 | ||||
| Time of sunset | 19:09 | ||||
| Length of day | 12:35 | ||||
| Our opinion about the weather in september | |||||
| Our opinion at whereandwhen.net | good | ||||
How was the weather last september?
Here is the day by day recorded weather in Thunder Bay in september 2024:
54°F to 65°F
49°F to 68°F
54°F to 70°F
63°F to 76°F
54°F to 68°F
43°F to 59°F
41°F to 63°F
49°F to 70°F
52°F to 68°F
56°F to 70°F
58°F to 72°F
58°F to 70°F
59°F to 72°F
59°F to 70°F
61°F to 76°F
65°F to 76°F
61°F to 74°F
63°F to 72°F
54°F to 70°F
63°F to 72°F
56°F to 68°F
52°F to 63°F
47°F to 63°F
47°F to 63°F
50°F to 76°F
54°F to 67°F
52°F to 68°F
52°F to 74°F
58°F to 70°F
47°F to 70°F
Map: other cities in Canada in september
Cities near Thunder Bay:
| Marathon in september | tolerable weather |
| Dryden in september | tolerable weather |
| Sault Ste. Marie in september | good weather |
| Red Lake in september | tolerable weather |
| Timmins in september | tolerable weather |
| Winnipeg (Manitoba) in september | good weather |
| Greater Sudbury in september | good weather |
| Bruce Peninsula in september | good weather |
| Owen Sound in september | good weather |
| North Bay in september | good weather |
| Brandon in september | good weather |
| Orillia in september | good weather |
Click over cities on the map for information about the weather in september.
Thunder Bay
perfect weather
good
tolerable
bad
very bad
Weather data for Thunder Bay in september:
Weather data for Thunder Bay for september are derived from an average of the weather forecast since 2009 in Thunder Bay. There is a margin of error and these forecasts are to be considered as general information only. The weather in Thunder Bay can vary slightly from year to year, but this data should limit surprises. So you can pack your bags or check for the best time in year to go to Thunder Bay.