September is one of the warmer months of the year in Baie-Comeau, with average highs near 14.5°C and lows around 8.7°C (mean 11.6°C). It is about average for rainfall, averaging 91 mm of rainfall and 84% relative humidity across the period.
September is one of the warmer months of the year in Baie-Comeau. Across 45 years of records, the warmest September in Baie-Comeau was 2023 — when the month averaged 15°C — while the coldest was 1986 at 8.9°C. Typical September days reach 14.5°C with nights near 8.7°C. The long-term trend is warming, about 0.5°C per decade.
September is about average for rainfall in Baie-Comeau, averaging 91 mm of rainfall. The wettest September on record was 2010 with 232 mm, while the driest was 2025 at 41 mm.
Relative humidity in Baie-Comeau during September averages 84%. The most humid September was 1987 at 87%, and the least humid was 1995 at 81%.
September receives about 3.3 kWh/m²/day of solar energy in Baie-Comeau. The sunniest September was 2015 at 3.8 kWh/m²/day, and the cloudiest was 1997 at 2.8.
Average wind speed in Baie-Comeau during September is 2.1 m/s. The windiest Septembers were 1984 and 2014 at 2.5 m/s, while the calmest were 2017 and 2024 at 1.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 10.6°C | 11.2°C | 11.7°C | 11.9°C | 13.0°C | +2.4°C |
| Avg High | 13.5°C | 14.1°C | 14.6°C | 14.6°C | 15.9°C | +2.4°C |
| Avg Low | 7.7°C | 8.4°C | 8.8°C | 9.2°C | 10.0°C | +2.3°C |
| Avg Rain | 87 mm | 83 mm | 100 mm | 104 mm | 71 mm | -16 mm |
September temperatures in Baie-Comeau have risen by about 2.3°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 0.3°C (2000) to a record high of 25°C (2010).
Rainfall in September is about average for rainfall, averaging 91 mm, with a wettest year of 232 mm.
One of the best times to visit Baie-Comeau
September is one of the best times to visit Baie-Comeau. Expect days averaging 14.5°C and nights around 8.7°C (mean 11.6°C) — warmer than Baie-Comeau's yearly average — with higher rainfall (91 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 16.0°C | 12.8°C | 9.6°C | 22.1°C | 6.0°C | 41 mm | 82% | 1.9 m/s | 3.7 |
| 2024 | 16.9°C | 13.7°C | 10.5°C | 22.7°C | 8.3°C | 48 mm | 83% | 1.7 m/s | 3.5 |
| 2023 🔥 | 17.9°C | 15.0°C | 12.1°C | 23.2°C | 7.2°C | 70 mm | 85% | 1.8 m/s | 3.6 |
| 2022 | 15.3°C | 12.4°C | 9.5°C | 21.8°C | 6.0°C | 46 mm | 83% | 2 m/s | 3.7 |
| 2021 | 15.6°C | 13.0°C | 10.4°C | 19.0°C | 6.2°C | 160 mm | 86% | 2.2 m/s | 3 |
| 2020 | 13.9°C | 11.0°C | 8.0°C | 19.2°C | 2.9°C | 61 mm | 84% | 2.3 m/s | 3.2 |
| 2019 | 12.9°C | 10.4°C | 7.8°C | 17.7°C | 3.0°C | 100 mm | 85% | 2.1 m/s | 3.2 |
| 2018 | 14.4°C | 11.6°C | 8.7°C | 20.7°C | 2.4°C | 98 mm | 84% | 2.3 m/s | 3.5 |
| 2017 | 15.3°C | 12.6°C | 10.0°C | 19.0°C | 3.8°C | 86 mm | 86% | 1.7 m/s | 3.2 |
| 2016 | 14.9°C | 12.2°C | 9.5°C | 20.3°C | 5.2°C | 98 mm | 86% | 2.1 m/s | 3.2 |
| 2015 | 16.3°C | 13.5°C | 10.6°C | 21.7°C | 3.6°C | 77 mm | 85% | 2 m/s | 3.8 |
| 2014 | 14.2°C | 11.4°C | 8.7°C | 21.2°C | 3.1°C | 96 mm | 82% | 2.5 m/s | 3.3 |
| 2013 | 13.7°C | 11.0°C | 8.3°C | 16.6°C | 4.9°C | 102 mm | 86% | 2.2 m/s | 2.9 |
| 2012 | 15.2°C | 12.3°C | 9.4°C | 20.4°C | 5.0°C | 66 mm | 84% | 2.1 m/s | 3.2 |
| 2011 | 15.4°C | 12.5°C | 9.5°C | 19.2°C | 5.6°C | 91 mm | 85% | 1.9 m/s | 3.7 |
| 2010 🌧️ | 14.1°C | 11.7°C | 9.4°C | 25.0°C | 4.7°C | 232 mm | 85% | 2.3 m/s | 2.9 |
| 2009 | 14.1°C | 11.2°C | 8.3°C | 19.3°C | 3.9°C | 61 mm | 84% | 1.9 m/s | 3.5 |
| 2008 | 14.5°C | 11.8°C | 9.1°C | 21.5°C | 2.8°C | 129 mm | 85% | 1.9 m/s | 3.2 |
| 2007 | 13.6°C | 10.8°C | 8.0°C | 21.1°C | 3.2°C | 134 mm | 83% | 2.3 m/s | 3.2 |
| 2006 | 14.5°C | 11.5°C | 8.5°C | 19.8°C | 5.0°C | 136 mm | 84% | 2 m/s | 3.4 |
| 2005 | 14.9°C | 12.2°C | 9.6°C | 20.0°C | 6.2°C | 103 mm | 85% | 2.3 m/s | 3.4 |
| 2004 | 14.3°C | 11.4°C | 8.4°C | 18.4°C | 4.9°C | 89 mm | 85% | 2 m/s | 3.5 |
| 2003 | 16.3°C | 13.1°C | 9.9°C | 22.4°C | 6.6°C | 105 mm | 85% | 1.8 m/s | 3.4 |
| 2002 | 15.2°C | 12.1°C | 8.9°C | 20.3°C | 3.9°C | 83 mm | 84% | 1.9 m/s | 3.3 |
| 2001 | 15.1°C | 12.2°C | 9.3°C | 22.9°C | 4.7°C | 96 mm | 84% | 2.1 m/s | 3.5 |
| 2000 | 13.7°C | 10.9°C | 8.2°C | 18.5°C | 0.3°C | 59 mm | 83% | 2.4 m/s | 3 |
| 1999 | 17.2°C | 14.3°C | 11.4°C | 24.1°C | 6.6°C | 130 mm | 84% | 2 m/s | 3.4 |
| 1998 | 14.7°C | 12.1°C | 9.6°C | 18.1°C | 5.3°C | 109 mm | 83% | 2.3 m/s | 3 |
| 1997 | 13.8°C | 11.3°C | 8.8°C | 19.5°C | 3.9°C | 52 mm | 85% | 2.2 m/s | 2.8 |
| 1996 | 14.4°C | 11.6°C | 8.8°C | 20.6°C | 4.5°C | 49 mm | 82% | 1.9 m/s | 3.5 |
| 1995 | 12.8°C | 9.8°C | 6.7°C | 17.2°C | 1.6°C | 68 mm | 81% | 2.2 m/s | 3.3 |
| 1994 | 13.7°C | 10.8°C | 8.0°C | 17.5°C | 4.8°C | 71 mm | 86% | 1.8 m/s | 3.3 |
| 1993 | 13.3°C | 10.2°C | 7.1°C | 18.1°C | 1.5°C | 88 mm | 83% | 2.2 m/s | 3.1 |
| 1992 | 14.3°C | 11.4°C | 8.5°C | 19.0°C | 1.9°C | 90 mm | 86% | 2.2 m/s | 3 |
| 1991 | 12.8°C | 9.9°C | 7.1°C | 17.7°C | 1.4°C | 59 mm | 82% | 2.2 m/s | 3.4 |
| 1990 | 13.8°C | 10.7°C | 7.6°C | 18.8°C | 2.9°C | 113 mm | 82% | 2.3 m/s | 3.3 |
| 1989 | 14.8°C | 11.5°C | 8.3°C | 20.7°C | 1.9°C | 56 mm | 82% | 2.3 m/s | 3.7 |
| 1988 | 12.2°C | 9.6°C | 7.0°C | 16.9°C | 3.4°C | 110 mm | 84% | 2.3 m/s | 3 |
| 1987 | 13.1°C | 10.4°C | 7.6°C | 19.8°C | 2.6°C | 98 mm | 87% | 2.1 m/s | 3.1 |
| 1986 ❄️ | 11.8°C | 8.9°C | 6.1°C | 17.3°C | 2.3°C | 117 mm | 82% | 2.3 m/s | 3.1 |
| 1985 | 14.6°C | 11.7°C | 8.7°C | 20.0°C | 4.6°C | 88 mm | 84% | 2 m/s | 3.3 |
| 1984 | 12.6°C | 9.7°C | 6.8°C | 18.8°C | 1.1°C | 66 mm | 83% | 2.5 m/s | 3.5 |
| 1983 | 14.8°C | 11.9°C | 8.9°C | 22.8°C | 4.9°C | 87 mm | 85% | 2 m/s | — |
| 1982 | 13.3°C | 10.5°C | 7.6°C | 19.2°C | 2.5°C | 86 mm | 85% | 1.8 m/s | — |
| 1981 | 14.4°C | 11.5°C | 8.6°C | 21.1°C | 4.6°C | 73 mm | 84% | 2.4 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 14.5°C with lows near 8.7°C (mean 11.6°C), based on 45 years of NASA POWER data.
September averages 91 mm of rainfall in Baie-Comeau, about average for rainfall. The wettest on record was 232 mm in 2010.
The hottest September reached 25°C in 2010. The coldest dipped to 0.3°C in 2000.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.3°C. Daytime highs moved from 13.9°C to 16.3°C and overnight lows from 8.1°C to 10.4°C over the same span.
September is one of the warmer months of the year in Baie-Comeau and about average for rainfall, so plan for around 14.5°C daytime highs and 8.7°C at night.
Not quite — September is the 9th coolest month in Baie-Comeau, averaging 11.6°C.
For September in Baie-Comeau, pack light layers you can adjust through the day, with typical highs of 14.5°C and lows of 8.7°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 84% — quite humid.
Average wind speed in September is 2.1 m/s. The windiest September on record averaged 2.5 m/s (1984).
The wettest September on record was 2010 with 232 mm. On average, September sees 91 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 Baie-Comeau behaves each September, 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 September specifically, along with year-by-year records and how the month has changed over the decades.
