Thunder Bay, Ontario, Canada Climate Change Severity

57
High
The current climate change severity in Thunder Bay is High, with a 21.4% worsening in the climate score compared to last 15 years. This suggests deteriorating conditions, with increasing negative impacts on weather patterns and environmental conditions.
Data: Jan. to Nov. (Historical Vs 2025) - Weather Data Only
Low
020
Moderate
40
High
60
Very High
80
Extreme
100


Thunder Bay Weather Condition Changes (Historic Vs 2025)

0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Historic
2025

Over the past 15 year(s), Thunder Bay temperature has changed by around +8.2%, and has experienced notable climate changes.

Sunny
Cloudy
Rainy
Snowy
Misty
Data: Jan. to Nov. (Historical Vs 2025)

Comparison of Weather Condition (Historic Vs 2025)

HistoricDays

Year 2025Days

Change

sunnySunny
4831
-35.4%

cloudyCloudy
8768
-21.8%

rainyRainy
10851
-52.7%

snowySnowy
1418
28.5%

mistyMisty
021
100%

Disclaimer: Other weather conditions not shown may affect the total day count.

Climate Change Indicators:

Over the past 15 years, Thunder Bay has experienced measurable shifts in key climate parameters, contributing to the current severity score of 57 (within the High severity category). This suggests worsening climate conditions from the previous years. Here’s a breakdown of the specific changes observed:

Severity Score

57/100


High

Low
020
Moderate
40
High
60
Very High
80
Extreme
100

From 2010 to 2025, Thunder Bay experienced significant changes:

Temperature change of

+0.3 °C


Variation in annual rainfall

+95.6 %


Change in average humidity

-6.1 %


PM2.5 levels surged by

-0.6 %


Heatwave changed by

-3.6 day(s)


Coldwave changed by

-12.4 day(s)


Wind speeds changed by

-0.5 km/h


These indicators show that Thunder Bay is experiencing a more volatile and extreme climate, reinforcing the need for urgent intervention to mitigate risks. As the severity score rises, focus must shift to adaptation and emergency preparedness.

Check how we calculate Climate Change Severity
Based on data from Jan. to Nov.

Thunder Bay Weather Forecast 30 Days (December - January 2026)
Thunder Bay, Ontario, Canada


Condition
Temperature IconTemperature
Humidity Iconhumi.
Wind IconWind Speed
Thu. 11, Dec.
sunnySunny

Temperature Icon-7°/-18°

Humidity Icon74%

Wind Icon22km/h
Fri. 12, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-3°/-8°

Humidity Icon84%

Wind Icon27km/h
Sat. 13, Dec.
overcastOvercast

Temperature Icon-15°/-19°

Humidity Icon70%

Wind Icon29km/h
Sun. 14, Dec.
partly cloudyPartly Cloudy

Temperature Icon-14°/-20°

Humidity Icon75%

Wind Icon22km/h
Mon. 15, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-8°/-13°

Humidity Icon83%

Wind Icon22km/h
Tue. 16, Dec.
overcastOvercast

Temperature Icon-3°/-14°

Humidity Icon89%

Wind Icon19km/h
Wed. 17, Dec.
light freezing rainLight freezing rain

Temperature Icon0°/-5°

Humidity Icon91%

Wind Icon15km/h
Thu. 18, Dec.
mistMist

Temperature Icon-1°/-9°

Humidity Icon93%

Wind Icon24km/h
Fri. 19, Dec.
partly cloudyPartly Cloudy

Temperature Icon-4°/-11°

Humidity Icon84%

Wind Icon24km/h
Sat. 20, Dec.
heavy snowHeavy snow

Temperature Icon-8°/-14°

Humidity Icon88%

Wind Icon18km/h
Sun. 21, Dec.
sunnySunny

Temperature Icon-16°/-20°

Humidity Icon80%

Wind Icon16km/h
Mon. 22, Dec.
partly cloudyPartly Cloudy

Temperature Icon-16°/-22°

Humidity Icon81%

Wind Icon19km/h
Tue. 23, Dec.
sunnySunny

Temperature Icon-19°/-25°

Humidity Icon84%

Wind Icon18km/h
Wed. 24, Dec.
mistMist

Temperature Icon-18°/-27°

Humidity Icon86%

Wind Icon17km/h
Thu. 25, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-5°/-10°

Humidity Icon88%

Wind Icon22km/h
Fri. 26, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-6°/-11°

Humidity Icon88%

Wind Icon20km/h
Sat. 27, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-5°/-11°

Humidity Icon89%

Wind Icon22km/h
Sun. 28, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-5°/-13°

Humidity Icon89%

Wind Icon21km/h
Mon. 29, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-6°/-12°

Humidity Icon87%

Wind Icon21km/h
Tue. 30, Dec.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-7°/-12°

Humidity Icon90%

Wind Icon19km/h
Wed. 31, Dec.
patchy moderate snowPatchy moderate snow

Temperature Icon-9°/-15°

Humidity Icon87%

Wind Icon22km/h
Thu. 1, Jan.
patchy moderate snowPatchy moderate snow

Temperature Icon-9°/-16°

Humidity Icon85%

Wind Icon20km/h
Fri. 2, Jan.
light freezing rainLight freezing rain

Temperature Icon-9°/-15°

Humidity Icon87%

Wind Icon21km/h
Sat. 3, Jan.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-7°/-15°

Humidity Icon87%

Wind Icon23km/h
Sun. 4, Jan.
patchy moderate snowPatchy moderate snow

Temperature Icon-9°/-15°

Humidity Icon86%

Wind Icon22km/h
Mon. 5, Jan.
patchy moderate snowPatchy moderate snow

Temperature Icon-9°/-16°

Humidity Icon88%

Wind Icon22km/h
Tue. 6, Jan.
patchy moderate snowPatchy moderate snow

Temperature Icon-9°/-16°

Humidity Icon89%

Wind Icon20km/h
Wed. 7, Jan.
moderate or heavy snow showersModerate or heavy snow showers

Temperature Icon-8°/-14°

Humidity Icon91%

Wind Icon22km/h
Thu. 8, Jan.
patchy moderate snowPatchy moderate snow

Temperature Icon-8°/-14°

Humidity Icon90%

Wind Icon22km/h
Fri. 9, Jan.
moderate snowModerate snow

Temperature Icon-6°/-15°

Humidity Icon90%

Wind Icon22km/h
Sat. 10, Jan.
patchy moderate snowPatchy moderate snow

Temperature Icon-7°/-13°

Humidity Icon89%

Wind Icon20km/h

Highest & Lowest Weather Forecasts

TemperatureTemperature

High will be onWed. 17, Dec.

0.1°C


Low will be onWed. 24, Dec.

-26.6°C

HumidityHumidity

High will be onThu. 18, Dec.

93%


Low will be onSat. 13, Dec.

70%

Wind SpeedWind Speed

High will be onSat. 13, Dec.

29.2km/h


Low will be onWed. 17, Dec.

15.1km/h

PrecipitationPrecipitation

High will be onFri. 12, Dec.

12.01mm


Low will be onSun. 14, Dec.

0.01mm

Ultraviolet IndexUV

High will be onFri. 19, Dec.

2


Low will be onTue. 16, Dec.

1