October is one of the warmer months of the year in Thunder Bay, with average highs near 9.7°C and lows around 1.5°C (mean 5.6°C). It is a relatively wet time of year, averaging 64 mm of rainfall and 80% relative humidity across the period.
October is one of the warmer months of the year in Thunder Bay. Across 45 years of records, the warmest October in Thunder Bay was 2021 — when the month averaged 10°C — while the coldest was 2002 at 2.1°C. Typical October days reach 9.7°C with nights near 1.5°C. The long-term trend is warming, about 0.7°C per decade.
October is a relatively wet time of year in Thunder Bay, averaging 64 mm of rainfall. The wettest October on record was 1998 with 145 mm, while the driest was 1992 at 21 mm.
Relative humidity in Thunder Bay during October averages 80%. The most humid October was 2018 at 86%, and the least humid was 2024 at 72%.
October receives about 2.1 kWh/m²/day of solar energy in Thunder Bay. The sunniest October was 2010 at 2.8 kWh/m²/day, and the cloudiest was 1984 at 1.6.
Average wind speed in Thunder Bay during October is 0.8 m/s. The windiest Octobers were 2020, 2023 and 2024, among others at 0.9 m/s, while the calmest were 1982, 1989 and 1992 at 0.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 4.5°C | 4.9°C | 5.5°C | 6.3°C | 7.4°C | +2.9°C |
| Avg High | 8.7°C | 9.2°C | 9.6°C | 10.2°C | 11.5°C | +2.8°C |
| Avg Low | 0.4°C | 0.6°C | 1.4°C | 2.3°C | 3.3°C | +2.9°C |
| Avg Rain | 64 mm | 70 mm | 75 mm | 56 mm | 50 mm | -14 mm |
October temperatures in Thunder Bay have risen by about 3.3°C between 1981–1985 and 2021–2025.
October has ranged from a record low of -11.8°C (1988) to a record high of 27.3°C (2023).
Rainfall in October is a relatively wet time of year, averaging 64 mm, with a wettest year of 145 mm.
A good time to visit Thunder Bay
October is a good time to visit Thunder Bay, with days averaging 9.7°C and nights around 1.5°C (mean 5.6°C, warmer than Thunder Bay's yearly average) and moderate rainfall. August and July are marginally more temperate, but October still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 13.7°C | 9.3°C | 4.9°C | 26.7°C | -2.2°C | 72 mm | 78% | 0.8 m/s | 2.5 |
| 2024 | 13.3°C | 8.7°C | 4.0°C | 19.8°C | -2.1°C | 47 mm | 72% | 0.9 m/s | 2.6 |
| 2023 | 10.7°C | 7.0°C | 3.3°C | 27.3°C | -5.2°C | 31 mm | 79% | 0.9 m/s | 2 |
| 2022 | 11.1°C | 6.7°C | 2.4°C | 20.0°C | -3.9°C | 42 mm | 80% | 0.8 m/s | 2.4 |
| 2021 🔥 | 14.1°C | 10.0°C | 5.9°C | 22.7°C | -2.4°C | 45 mm | 82% | 0.8 m/s | 2 |
| 2020 | 6.3°C | 2.7°C | -0.9°C | 19.2°C | -9.6°C | 65 mm | 74% | 0.9 m/s | 2 |
| 2019 | 9.1°C | 5.4°C | 1.7°C | 17.2°C | -4.9°C | 65 mm | 81% | 0.9 m/s | 2.1 |
| 2018 | 5.8°C | 2.5°C | -0.8°C | 12.4°C | -8.8°C | 93 mm | 86% | 0.9 m/s | 1.7 |
| 2017 | 11.8°C | 7.6°C | 3.5°C | 19.7°C | -7.8°C | 69 mm | 79% | 0.9 m/s | 2.2 |
| 2016 | 12.0°C | 7.9°C | 3.8°C | 21.2°C | -2.7°C | 45 mm | 80% | 0.9 m/s | 2.1 |
| 2015 | 10.8°C | 6.5°C | 2.2°C | 22.9°C | -4.2°C | 51 mm | 79% | 0.9 m/s | 2.4 |
| 2014 | 9.3°C | 5.6°C | 1.8°C | 16.3°C | -4.6°C | 42 mm | 83% | 0.8 m/s | 2.1 |
| 2013 | 9.7°C | 6.0°C | 2.4°C | 20.6°C | -5.0°C | 40 mm | 79% | 0.8 m/s | 2.1 |
| 2012 | 9.0°C | 5.2°C | 1.4°C | 21.3°C | -4.6°C | 53 mm | 80% | 0.9 m/s | 2 |
| 2011 | 12.7°C | 8.2°C | 3.8°C | 24.6°C | -3.8°C | 56 mm | 81% | 0.8 m/s | 2.5 |
| 2010 | 12.3°C | 7.6°C | 3.0°C | 23.3°C | -3.0°C | 49 mm | 74% | 0.9 m/s | 2.8 |
| 2009 | 7.0°C | 3.6°C | 0.3°C | 12.6°C | -3.8°C | 50 mm | 84% | 0.8 m/s | 2 |
| 2008 | 10.2°C | 6.2°C | 2.3°C | 19.1°C | -3.6°C | 43 mm | 82% | 0.9 m/s | 2.1 |
| 2007 | 11.8°C | 7.8°C | 3.7°C | 22.9°C | -4.1°C | 139 mm | 83% | 0.9 m/s | 2 |
| 2006 | 8.7°C | 4.5°C | 0.4°C | 21.3°C | -4.1°C | 36 mm | 74% | 0.9 m/s | 2.4 |
| 2005 | 11.8°C | 7.5°C | 3.3°C | 24.6°C | -2.7°C | 115 mm | 85% | 0.8 m/s | 2.1 |
| 2004 | 10.4°C | 6.4°C | 2.4°C | 20.8°C | -5.7°C | 95 mm | 83% | 0.8 m/s | 1.9 |
| 2003 | 8.9°C | 4.8°C | 0.7°C | 23.1°C | -4.4°C | 59 mm | 84% | 0.8 m/s | 2.1 |
| 2002 ❄️ | 5.9°C | 2.1°C | -1.8°C | 19.1°C | -7.7°C | 76 mm | 78% | 0.8 m/s | 2 |
| 2001 | 9.5°C | 5.4°C | 1.3°C | 20.7°C | -4.4°C | 80 mm | 82% | 0.9 m/s | 2.3 |
| 2000 | 11.6°C | 6.6°C | 1.7°C | 19.7°C | -3.1°C | 56 mm | 78% | 0.8 m/s | 2.4 |
| 1999 | 8.7°C | 4.4°C | 0.1°C | 14.6°C | -4.1°C | 62 mm | 79% | 0.9 m/s | 1.9 |
| 1998 🌧️ | 11.3°C | 7.1°C | 3.0°C | 18.1°C | -3.2°C | 145 mm | 82% | 0.9 m/s | 2.1 |
| 1997 | 9.5°C | 5.1°C | 0.7°C | 22.3°C | -9.5°C | 60 mm | 79% | 0.8 m/s | 2.2 |
| 1996 | 9.2°C | 4.8°C | 0.4°C | 17.4°C | -9.2°C | 107 mm | 83% | 0.9 m/s | 2 |
| 1995 | 8.4°C | 4.7°C | 1.0°C | 20.2°C | -5.1°C | 82 mm | 81% | 0.9 m/s | 1.9 |
| 1994 | 12.3°C | 7.8°C | 3.2°C | 19.7°C | -2.7°C | 28 mm | 77% | 0.8 m/s | 2.1 |
| 1993 | 7.4°C | 2.9°C | -1.5°C | 18.8°C | -5.0°C | 33 mm | 75% | 0.8 m/s | 1.9 |
| 1992 | 9.1°C | 4.7°C | 0.3°C | 22.2°C | -4.9°C | 21 mm | 76% | 0.7 m/s | 1.9 |
| 1991 | 7.3°C | 3.1°C | -1.0°C | 16.8°C | -5.8°C | 65 mm | 77% | 0.8 m/s | 2.1 |
| 1990 | 8.4°C | 4.0°C | -0.4°C | 16.7°C | -8.6°C | 93 mm | 79% | 0.8 m/s | 2.2 |
| 1989 | 10.4°C | 5.6°C | 0.9°C | 20.5°C | -4.7°C | 26 mm | 73% | 0.7 m/s | 2.5 |
| 1988 | 7.1°C | 3.0°C | -1.1°C | 17.3°C | -11.8°C | 49 mm | 78% | 0.8 m/s | 2.1 |
| 1987 | 7.0°C | 2.6°C | -1.7°C | 16.9°C | -5.1°C | 41 mm | 77% | 0.9 m/s | 2.1 |
| 1986 | 8.9°C | 4.5°C | 0.1°C | 18.0°C | -5.9°C | 42 mm | 82% | 0.8 m/s | 2 |
| 1985 | 9.3°C | 4.8°C | 0.4°C | 14.0°C | -3.9°C | 57 mm | 81% | 0.8 m/s | 2.4 |
| 1984 | 10.7°C | 6.5°C | 2.4°C | 17.9°C | -6.6°C | 75 mm | 84% | 0.8 m/s | 1.6 |
| 1983 | 9.2°C | 5.1°C | 0.9°C | 16.7°C | -4.9°C | 71 mm | 84% | 0.8 m/s | — |
| 1982 | 9.0°C | 5.7°C | 2.4°C | 14.6°C | -4.0°C | 145 mm | 86% | 0.7 m/s | — |
| 1981 | 6.3°C | 2.7°C | -0.9°C | 12.9°C | -9.6°C | 72 mm | 83% | 0.8 m/s | — |
Actual recorded October data for each year, 1981–2025 — sourced from NASA POWER.
The average high in October is around 9.7°C with lows near 1.5°C (mean 5.6°C), based on 45 years of NASA POWER data.
October averages 64 mm of rainfall in Thunder Bay, a relatively wet time of year. The wettest on record was 145 mm in 1998.
The hottest October reached 27.3°C in 2023. The coldest dipped to -11.8°C in 1988.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average October temperatures have risen by about 3.3°C. Daytime highs moved from 8.9°C to 12.6°C and overnight lows from 1°C to 4.1°C over the same span.
October is one of the warmer months of the year in Thunder Bay and a relatively wet time of year, so plan for around 9.7°C daytime highs and 1.5°C at night.
Not quite — October is the 7th coolest month in Thunder Bay, averaging 5.6°C.
For October in Thunder Bay, pack warm layers and a jacket for chilly mornings, with typical highs of 9.7°C and lows of 1.5°C. Bring an umbrella or light rain jacket too.
Relative humidity in October averages 80% — quite humid.
Average wind speed in October is 0.8 m/s. The windiest October on record averaged 0.9 m/s (1987).
The wettest October on record was 1998 with 145 mm. On average, October sees 64 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Thunder Bay behaves each October, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for October specifically, along with year-by-year records and how the month has changed over the decades.
