Will it rain tomorrow in Thunder Bay?

rain unlikely. Rain: 0.4 mm. Low 2 °C, High 7 °C.

What will the weather be like at the weekend in Thunder Bay?

Sat 17/10: clear sky, 2 °C / 14 °C, no rain expected.

How far ahead does this Thunder Bay forecast go?

This page shows 7 days. The model run used here is from 16/10/2026, 01:18 UTC, and the page fetches a new one every 30 minutes.

Thunder Bay weather

Temperature, rain and wind in Thunder Bay (Ontario, Canada), a city of about 108,843 people: how it is right now, hour by hour into tomorrow, the next 7 days and what each month of the year is like.

Right now

Thursday 15 October, 23:00 (America/Toronto)

7 °C

Rain

Feels like

4 °C

Humidity

94%

Wind

17 km/h

NNW · Beaufort 3

Dew point

6 °C

Cloud cover

100%

Pressure

1,013 hPa

Hour by hour

Next 24 hours, in the city’s local time.

Time	Conditions	Temperature	Rain	Wind
22:00	Rain	7 °C	0.6 mm	15 km/h
23:00	Rain	7 °C	0.5 mm	17 km/h
00:00	Rain	7 °C	0.3 mm	17 km/h
01:00	Light rain	6 °C	0.1 mm	19 km/h
02:00	Cloudy	6 °C	0.0 mm	21 km/h
03:00	Cloudy	6 °C	0.0 mm	27 km/h
04:00	Cloudy	6 °C	0.0 mm	30 km/h
05:00	Cloudy	6 °C	0.0 mm	31 km/h
06:00	Cloudy	6 °C	0.0 mm	33 km/h
07:00	Cloudy	5 °C	0.0 mm	32 km/h
08:00	Cloudy	5 °C	0.0 mm	35 km/h
09:00	Cloudy	5 °C	0.0 mm	37 km/h
10:00	Cloudy	5 °C	0.0 mm	39 km/h
11:00	Cloudy	4 °C	0.0 mm	37 km/h
12:00	Partly cloudy	4 °C	0.0 mm	35 km/h
13:00	Fair	6 °C	0.0 mm	30 km/h
14:00	Fair	7 °C	0.0 mm	28 km/h
15:00	Partly cloudy	7 °C	0.0 mm	28 km/h
16:00	Fair	7 °C	0.0 mm	29 km/h
17:00	Clear sky	7 °C	0.0 mm	24 km/h
18:00	Clear sky	7 °C	0.0 mm	18 km/h
19:00	Clear sky	6 °C	0.0 mm	14 km/h
20:00	Clear sky	4 °C	0.0 mm	14 km/h
21:00	Clear sky	4 °C	0.0 mm	11 km/h

Next 7 days

Day	Conditions	Low	High	Rain outlook
Thu 15/10	Rain	6 °C	7 °C	rain likely · 1.1 mm
Fri 16/10	Partly cloudy	2 °C	7 °C	rain unlikely · 0.4 mm
Sat 17/10	Clear sky	2 °C	14 °C	no rain expected · 0.0 mm
Mon 19/10	Clear sky	4 °C	13 °C	no rain expected · 0.0 mm
Tue 20/10	Cloudy	5 °C	11 °C	rain unlikely · 0.1 mm
Wed 21/10	Partly cloudy	9 °C	13 °C	rain unlikely · 0.1 mm
Thu 22/10	Clear sky	5 °C	14 °C	no rain expected · 0.0 mm

This column is our own reading: the global model does not publish a probability of precipitation for this region, so we classify the day from the forecast symbol and the total in millimetres. It is not an official probability figure.

Our own chart, drawn from the 7-day forecast for Thunder Bay shown above.

What each number means

Rain (mm): 1 millimetre of rain is 1 litre of water per square metre. Up to 2 mm in a day is drizzle; from 10 mm it is proper rain; more than 50 mm in a few hours is the amount that floods streets.
Humidity: Relative humidity is how much water vapour the air holds compared with the most it can hold at that temperature. Above 80% sweat evaporates slowly and heat feels worse; below 30% your throat and eyes dry out.
Dew point: The dew point is the temperature at which the air would start to condense. The closer it is to the air temperature, the muggier it feels. Above 20 °C the air already feels heavy.
Feels like: "Feels like" combines temperature, wind and humidity: strong wind carries heat away from the body, so it feels colder than the thermometer; high humidity in the heat makes it feel warmer.
Wind: Wind is given as a speed and the direction it blows from. Up to 20 km/h you barely notice it; at 40 km/h it moves branches and parasols; above 60 km/h it brings down trees and roof tiles.
Cloud cover: Cloud cover as a percentage is how much of the sky is covered. Up to 20% is a clear sky; above 80% the sun barely gets through.
Chance of rain: The model does not publish a probability of precipitation for this region. This column is our own reading: the global model does not publish a probability of precipitation for this region, so we classify the day from the forecast symbol and the total in millimetres. It is not an official probability figure.

Month-by-month climate

In October, Thunder Bay averages 5 °C and about 66 mm of rain over the month, on the 25-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2025) climatology.

Warmest month

July

Coldest month

January

Wettest month

June

Driest month

February

Month	Mean temperature	Rain	Mean humidity
January	-14 °C	26 mm	97%
February	-13 °C	20 mm	96%
March	-5 °C	30 mm	85%
April	2 °C	55 mm	72%
May	9 °C	72 mm	72%
June	14 °C	86 mm	75%
July	18 °C	75 mm	75%
August	18 °C	59 mm	74%
September	13 °C	70 mm	78%
October	5 °C	66 mm	81%
November	-2 °C	40 mm	84%
December	-10 °C	33 mm	93%

Our own chart, from the NASA POWER 25-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2025) climatology for the coordinates of Thunder Bay.

Frequently asked questions

Will it rain tomorrow in Thunder Bay?: rain unlikely. Rain: 0.4 mm. Low 2 °C, High 7 °C.
What is the temperature in Thunder Bay right now?: 7 °C, rain. Feels like: 4 °C. Humidity: 94%.
What will the weather be like at the weekend in Thunder Bay?: Sat 17/10: clear sky, 2 °C / 14 °C, no rain expected.
Which is the wettest month in Thunder Bay?: June — ~86 mm (25-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2025), NASA POWER).
How far ahead does this Thunder Bay forecast go?: This page shows 7 days. The model run used here is from 16/10/2026, 01:18 UTC, and the page fetches a new one every 30 minutes.

Nearby cities

Forecasts for places near Thunder Bay:

How to read this page

How to read the min and the max

The week’s high (14 °C) arrives in the afternoon, about two hours after solar noon; the low (2 °C) just before sunrise. Both are air temperature in the shade, two metres above ground — in direct sun or over asphalt a thermometer reads higher.

Where this number comes from

The Thunder Bay forecast comes from MET Norway, a partir do ECMWF HRES e, na área nórdica, do MEPS, run of 16/10/2026, 01:18 UTC. The month-by-month climate comes from NASA POWER, climatology of 25-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2025). Both are credited in full at the foot of this page.

What a forecast cannot promise

Out to two days accuracy is high; by day seven the trend matters more than the exact figure. For Thunder Bay the model publishes no rain probability, so the expectation column is our reading.

Severe weather warnings

This page is informational. For official warnings of storms, gales or flooding affecting Thunder Bay, go to your national weather service through the World Meteorological Organization warning portal.

WMO Severe Weather Information Centre

Understanding the weather and climate of Thunder Bay

Is this week in Thunder Bay above or below the October normal?

The average of the next 7 days in Thunder Bay works out at 8 °C, against a normal of 5 °C for October over 25-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2025). That is 3 °C above typical — a small gap, the size the atmosphere wanders from one week to the next.

Within the week the highest maximum lands on Sat 17/10 (14 °C) and the lowest minimum on Fri 16/10 (2 °C). Forecast rain adds up to 1.7 mm, roughly 3% of everything Thunder Bay gets in an average October (66 mm). The wettest day is Thu 15/10, with 1.1 mm.

When is the wettest and the driest month in Thunder Bay?

On the 25-year Meteorological and Solar Monthly & Annual Climatologies (January 2001 - December 2025) climatology, the wettest month in Thunder Bay is June, at about 86 mm, and the driest is February, at 20 mm. June takes 4.3 times more than February, so rain in Thunder Bay has a real season even though it never stops altogether. For October, the month you are reading this in, the average is 66 mm.

What does the dew point say about how Thunder Bay feels?

Right now in Thunder Bay the air is at 7 °C with a dew point of 6 °C and relative humidity of 94%. The two sit within a few tenths of each other: the air is all but saturated, which favours fog, dew on the car and laundry that will not dry.

What is the climate of Thunder Bay like through the year?

The warmest month in Thunder Bay is July (18 °C on average) and the coldest is January (-14 °C), a swing of about 31 °C around an annual mean of 3 °C. A swing above twenty degrees is continental: summer and winter are almost two climates at the same address.

Because Thunder Bay lies in the northern hemisphere, at 48.38° north, summer falls in June, July and August, in the middle of the calendar.

How far is Thunder Bay from Winnipeg?

The nearest large city to Thunder Bay is Winnipeg, about 598 km away in a straight line, to the west, with 749,607 inhabitants. With more than two hundred kilometres between them, using the Winnipeg forecast for Thunder Bay is a common mistake: these are weather regimes that can diverge for days. Being larger, Winnipeg shows up in more searches, and plenty of people end up reading its forecast assuming it covers Thunder Bay.

Words on this page

Apparent temperature

The temperature the body actually feels, rather than the one on the thermometer. It combines air temperature with wind, which carries heat away faster, and humidity, which slows the evaporation of sweat. That is why 30 °C in dry air with a breeze is easier than 28 °C in still, muggy air.

Apparent temperature

Dew point

The temperature air would have to cool to, at constant pressure and moisture, for water to start condensing. The closer the dew point sits to the air temperature, the less room the vapour has and the muggier the day feels.

Dew point

Millimetre of rain

The depth of water rain would leave on a flat surface with no run-off. One millimetre is one litre per square metre, no matter how large the area measured is.

Standard definition by World Meteorological Organization (WMO) · Millimetre of rain

Relative humidity

How much water vapour the air holds compared with the most it could hold at that temperature, as a percentage. Because that ceiling rises with heat, the same amount of vapour reads high at dawn and low in the afternoon.

Relative humidity

Climate normal

The average of a climate element — temperature, rainfall, humidity — computed over a long, standardised period, usually thirty years. It does not predict anything: it says what is typical for that place in that month, and gives you a ruler for calling a week warm or wet.

Standard definition by World Meteorological Organization (WMO) · Climate normal

Forecast model

A program that solves the equations of the atmosphere on a grid of points and steps forward in time from the state observed now. Your city forecast is the model value at the nearest grid point, which is why two neighbouring towns get almost the same numbers.

Standard definition by MET Norway (Meteorologisk institutt) · Forecast model

Model run

The time the model was executed with the latest observations. Every forecast belongs to a run, and runs age: one from six hours ago knows nothing about the shower that started afterwards. It is the first thing to check when two sources disagree.

Standard definition by MET Norway (Meteorologisk institutt) · Model run

See the full weather glossary

Source, model and licence

Model: MET Norway, a partir do ECMWF HRES e, na área nórdica, do MEPS
Model run: 16/10/2026, 01:18 UTC
Source: MET Norway (Meteorologisk institutt) — Locationforecast 2.0 — Based on data from MET Norway. Licence: CC BY 4.0 / NLOD 2.0.
Month-by-month climate: NASA POWER — Climatology (MERRA-2, 2001–2020) — The data was obtained from National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project — Climatology API v2. Dados públicos da NASA, citação obrigatória.
Cities, coordinates and population: Dados de cidades: GeoNames (CC BY 4.0)

The page fetches fresh data every 30 minutes. Informational content. For severe weather warnings, follow your country’s official weather service and civil protection authority.