October is one of the warmer months of the year in Ottawa, with average highs near 13.1°C and lows around 3.3°C (mean 8.2°C). It is about average for rainfall, averaging 90 mm of rainfall and 81% relative humidity across the period.
October is one of the warmer months of the year in Ottawa. Across 45 years of records, the warmest October in Ottawa was 2021 — when the month averaged 12°C — while the coldest was 1981 at 4.6°C. Typical October days reach 13.1°C with nights near 3.3°C. The long-term trend is warming, about 0.7°C per decade.
October is about average for rainfall in Ottawa, averaging 90 mm of rainfall. The wettest October on record was 1995 with 169 mm, while the driest was 1994 at 19 mm.
Relative humidity in Ottawa during October averages 81%. The most humid October was 1981 at 85%, and the least humid was 2015 at 73%.
October receives about 2.4 kWh/m²/day of solar energy in Ottawa. The sunniest October was 2025 at 3 kWh/m²/day, and the cloudiest were 1988 and 2006 at 2.
Average wind speed in Ottawa during October is 0.3 m/s. The windiest Octobers were 2023, 2024 and 2025, among others at 0.3 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 7.1°C | 7.6°C | 8.0°C | 9.0°C | 10.1°C | +3°C |
| Avg High | 12.1°C | 12.6°C | 12.7°C | 13.8°C | 15.3°C | +3.2°C |
| Avg Low | 2.0°C | 2.6°C | 3.2°C | 4.1°C | 4.9°C | +2.9°C |
| Avg Rain | 86 mm | 86 mm | 96 mm | 96 mm | 80 mm | -6 mm |
October temperatures in Ottawa have risen by about 3.2°C between 1981–1985 and 2021–2025.
October has ranged from a record low of -6.8°C (1997) to a record high of 29.6°C (2025).
Rainfall in October is about average for rainfall, averaging 90 mm, with a wettest year of 169 mm.
A good time to visit Ottawa
October is a good time to visit Ottawa, with days averaging 13.1°C and nights around 3.3°C (mean 8.2°C, warmer than Ottawa's yearly average) and higher rainfall. July and August 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 | 16.1°C | 10.4°C | 4.7°C | 29.6°C | -2.5°C | 110 mm | 76% | 0.3 m/s | 3 |
| 2024 | 15.5°C | 9.8°C | 4.0°C | 24.1°C | -5.7°C | 46 mm | 77% | 0.3 m/s | 2.9 |
| 2023 | 16.0°C | 11.4°C | 6.8°C | 28.7°C | -6.0°C | 88 mm | 82% | 0.3 m/s | 2.1 |
| 2022 | 15.4°C | 9.4°C | 3.4°C | 22.1°C | -1.9°C | 37 mm | 77% | 0.3 m/s | 2.9 |
| 2021 🔥 | 16.4°C | 12.0°C | 7.6°C | 24.2°C | 0.3°C | 115 mm | 84% | 0.3 m/s | 2.2 |
| 2020 | 12.3°C | 7.6°C | 2.8°C | 22.6°C | -5.8°C | 86 mm | 80% | 0.3 m/s | 2.2 |
| 2019 | 14.1°C | 9.1°C | 4.0°C | 19.8°C | -0.8°C | 143 mm | 83% | 0.3 m/s | 2.3 |
| 2018 | 11.3°C | 6.6°C | 1.9°C | 27.0°C | -4.1°C | 61 mm | 78% | 0.3 m/s | 2.1 |
| 2017 | 16.7°C | 11.6°C | 6.6°C | 25.3°C | -0.2°C | 149 mm | 83% | 0.3 m/s | 2.5 |
| 2016 | 14.0°C | 9.1°C | 4.1°C | 24.6°C | -3.5°C | 114 mm | 79% | 0.3 m/s | 2.4 |
| 2015 | 12.3°C | 7.1°C | 2.0°C | 23.1°C | -5.2°C | 84 mm | 73% | 0.3 m/s | 2.7 |
| 2014 | 14.5°C | 10.0°C | 5.5°C | 23.6°C | -0.5°C | 83 mm | 83% | 0.3 m/s | 2.2 |
| 2013 | 14.3°C | 9.4°C | 4.5°C | 22.5°C | -5.7°C | 86 mm | 80% | 0.3 m/s | 2.6 |
| 2012 | 14.4°C | 9.8°C | 5.3°C | 22.1°C | -1.1°C | 82 mm | 80% | 0.3 m/s | 2.2 |
| 2011 | 14.2°C | 9.5°C | 4.7°C | 24.8°C | -4.0°C | 74 mm | 79% | 0.3 m/s | 2.3 |
| 2010 | 12.1°C | 7.3°C | 2.6°C | 19.3°C | -4.3°C | 87 mm | 79% | 0.3 m/s | 2.5 |
| 2009 | 10.4°C | 6.2°C | 1.9°C | 17.0°C | -4.3°C | 96 mm | 84% | 0.3 m/s | 2.2 |
| 2008 | 12.2°C | 7.3°C | 2.4°C | 22.1°C | -5.8°C | 96 mm | 82% | 0.3 m/s | 2.6 |
| 2007 | 15.8°C | 10.7°C | 5.5°C | 25.4°C | -4.0°C | 105 mm | 83% | 0.3 m/s | 2.4 |
| 2006 | 11.2°C | 6.9°C | 2.6°C | 21.7°C | -2.6°C | 121 mm | 84% | 0.3 m/s | 2 |
| 2005 | 13.8°C | 9.5°C | 5.1°C | 27.0°C | -2.9°C | 109 mm | 84% | 0.3 m/s | 2.2 |
| 2004 | 13.9°C | 8.7°C | 3.5°C | 22.3°C | -1.6°C | 57 mm | 82% | 0.3 m/s | 2.6 |
| 2003 | 11.2°C | 6.8°C | 2.4°C | 23.3°C | -3.1°C | 160 mm | 84% | 0.3 m/s | 2.2 |
| 2002 | 11.2°C | 6.3°C | 1.4°C | 26.6°C | -5.5°C | 92 mm | 79% | 0.3 m/s | 2.5 |
| 2001 | 13.9°C | 9.2°C | 4.6°C | 23.4°C | -3.7°C | 98 mm | 80% | 0.3 m/s | 2.4 |
| 2000 | 13.2°C | 8.1°C | 2.9°C | 21.3°C | -3.3°C | 29 mm | 82% | 0.3 m/s | 2.5 |
| 1999 | 12.4°C | 7.1°C | 1.8°C | 19.7°C | -4.3°C | 74 mm | 77% | 0.3 m/s | 2.5 |
| 1998 | 14.1°C | 9.1°C | 4.0°C | 20.4°C | -0.5°C | 71 mm | 77% | 0.3 m/s | 2.8 |
| 1997 | 12.0°C | 6.9°C | 1.7°C | 24.1°C | -6.8°C | 50 mm | 77% | 0.3 m/s | 2.8 |
| 1996 | 12.1°C | 7.3°C | 2.5°C | 22.0°C | -3.9°C | 89 mm | 79% | 0.3 m/s | 2.3 |
| 1995 🌧️ | 14.2°C | 9.5°C | 4.8°C | 23.6°C | -3.7°C | 169 mm | 81% | 0.3 m/s | 2.2 |
| 1994 | 13.7°C | 8.4°C | 3.1°C | 21.0°C | -2.5°C | 19 mm | 79% | 0.3 m/s | 2.6 |
| 1993 | 11.0°C | 6.0°C | 1.1°C | 20.4°C | -4.8°C | 105 mm | 80% | 0.3 m/s | 2.2 |
| 1992 | 10.2°C | 5.4°C | 0.5°C | 19.4°C | -5.1°C | 60 mm | 82% | 0.3 m/s | 2.2 |
| 1991 | 13.6°C | 8.4°C | 3.2°C | 24.7°C | -3.8°C | 105 mm | 82% | 0.3 m/s | 2.4 |
| 1990 | 12.2°C | 7.6°C | 2.9°C | 23.5°C | -5.5°C | 113 mm | 84% | 0.3 m/s | 2.2 |
| 1989 | 13.8°C | 8.4°C | 3.1°C | 21.0°C | -3.9°C | 110 mm | 82% | 0.3 m/s | 2.4 |
| 1988 | 9.8°C | 5.5°C | 1.2°C | 23.9°C | -5.9°C | 121 mm | 83% | 0.3 m/s | 2 |
| 1987 | 11.1°C | 6.0°C | 0.9°C | 18.4°C | -5.4°C | 69 mm | 81% | 0.3 m/s | 2.5 |
| 1986 | 11.8°C | 6.6°C | 1.4°C | 19.1°C | -5.7°C | 78 mm | 82% | 0.3 m/s | 2.5 |
| 1985 | 12.9°C | 7.8°C | 2.8°C | 19.4°C | -5.3°C | 88 mm | 80% | 0.3 m/s | 2.5 |
| 1984 | 14.3°C | 9.0°C | 3.6°C | 21.7°C | -5.0°C | 47 mm | 80% | 0.3 m/s | 2.9 |
| 1983 | 12.3°C | 7.3°C | 2.2°C | 25.2°C | -5.1°C | 119 mm | 81% | 0.3 m/s | — |
| 1982 | 13.5°C | 8.3°C | 3.1°C | 20.8°C | -3.9°C | 35 mm | 81% | 0.3 m/s | — |
| 1981 ❄️ | 9.3°C | 4.6°C | -0.1°C | 15.7°C | -5.4°C | 105 mm | 85% | 0.3 m/s | — |
Actual recorded October data for each year, 1981–2025 — sourced from NASA POWER.
The average high in October is around 13.1°C with lows near 3.3°C (mean 8.2°C), based on 45 years of NASA POWER data.
October averages 90 mm of rainfall in Ottawa, about average for rainfall. The wettest on record was 169 mm in 1995.
The hottest October reached 29.6°C in 2025. The coldest dipped to -6.8°C in 1997.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average October temperatures have risen by about 3.2°C. Daytime highs moved from 12.5°C to 15.9°C and overnight lows from 2.3°C to 5.3°C over the same span.
October is one of the warmer months of the year in Ottawa and about average for rainfall, so plan for around 13.1°C daytime highs and 3.3°C at night.
Not quite — October is the 7th coolest month in Ottawa, averaging 8.2°C.
For October in Ottawa, pack warm layers and a jacket for chilly mornings, with typical highs of 13.1°C and lows of 3.3°C. Bring an umbrella or light rain jacket too.
Relative humidity in October averages 81% — quite humid.
Average wind speed in October is 0.3 m/s. The windiest October on record averaged 0.3 m/s (1981).
The wettest October on record was 1995 with 169 mm. On average, October sees 90 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 Ottawa 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.
