September is one of the warmer months of the year in Rivière-du-Loup, with average highs near 16.7°C and lows around 8.4°C (mean 12.6°C). It is about average for rainfall, averaging 80 mm of rainfall and 80% relative humidity across the period.
September is one of the warmer months of the year in Rivière-du-Loup. Across 45 years of records, the warmest September in Rivière-du-Loup was 2023 — when the month averaged 15.6°C — while the coldest was 1986 at 9.5°C. Typical September days reach 16.7°C with nights near 8.4°C. The long-term trend is warming, about 0.6°C per decade.
September is about average for rainfall in Rivière-du-Loup, averaging 80 mm of rainfall. The wettest September on record was 2010 with 210 mm, while the driest was 2025 at 24 mm.
Relative humidity in Rivière-du-Loup during September averages 80%. The most humid September was 2004 at 85%, and the least humid was 1995 at 74%.
September receives about 3.6 kWh/m²/day of solar energy in Rivière-du-Loup. The sunniest September was 2015 at 4.2 kWh/m²/day, and the cloudiest was 1997 at 2.9.
Average wind speed in Rivière-du-Loup during September is 1.4 m/s. The windiest September was 1988 at 1.8 m/s, while the calmest was 2023 at 1.1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 11.4°C | 12.1°C | 12.8°C | 13.1°C | 13.8°C | +2.4°C |
| Avg High | 15.5°C | 16.3°C | 16.9°C | 17.1°C | 18.3°C | +2.8°C |
| Avg Low | 7.4°C | 7.9°C | 8.7°C | 9.0°C | 9.4°C | +2°C |
| Avg Rain | 66 mm | 82 mm | 98 mm | 89 mm | 51 mm | -16 mm |
September temperatures in Rivière-du-Loup have risen by about 2.5°C between 1981–1985 and 2021–2025.
September has ranged from a record low of -0.8°C (2000) to a record high of 29.1°C (1999).
Rainfall in September is about average for rainfall, averaging 80 mm, with a wettest year of 210 mm.
One of the best times to visit Rivière-du-Loup
September is one of the best times to visit Rivière-du-Loup. Expect days averaging 16.7°C and nights around 8.4°C (mean 12.6°C) — warmer than Rivière-du-Loup's yearly average — with moderate rainfall (80 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 | 18.4°C | 13.5°C | 8.7°C | 24.8°C | 4.5°C | 24 mm | 75% | 1.2 m/s | 4 |
| 2024 | 19.6°C | 14.8°C | 10.0°C | 25.9°C | 6.4°C | 32 mm | 78% | 1.2 m/s | 4 |
| 2023 🔥 | 20.1°C | 15.6°C | 11.2°C | 28.7°C | 5.3°C | 59 mm | 80% | 1.1 m/s | 3.6 |
| 2022 | 17.9°C | 13.4°C | 8.9°C | 26.3°C | 4.4°C | 39 mm | 75% | 1.3 m/s | 4 |
| 2021 | 17.6°C | 13.7°C | 9.9°C | 21.6°C | 6.2°C | 104 mm | 80% | 1.4 m/s | 3.5 |
| 2020 | 16.3°C | 12.0°C | 7.8°C | 22.5°C | 0.5°C | 47 mm | 78% | 1.6 m/s | 3.8 |
| 2019 | 15.1°C | 11.3°C | 7.5°C | 21.4°C | 1.0°C | 96 mm | 82% | 1.3 m/s | 3.3 |
| 2018 | 17.6°C | 13.1°C | 8.6°C | 25.5°C | 0.2°C | 66 mm | 78% | 1.5 m/s | 3.8 |
| 2017 | 18.4°C | 14.2°C | 9.9°C | 27.1°C | 2.7°C | 62 mm | 82% | 1.2 m/s | 3.5 |
| 2016 | 17.9°C | 13.7°C | 9.4°C | 25.8°C | 3.2°C | 70 mm | 79% | 1.3 m/s | 4 |
| 2015 | 19.5°C | 15.1°C | 10.7°C | 26.2°C | 4.0°C | 59 mm | 80% | 1.3 m/s | 4.2 |
| 2014 | 16.5°C | 12.3°C | 8.2°C | 24.2°C | 1.5°C | 77 mm | 79% | 1.6 m/s | 3.6 |
| 2013 | 16.0°C | 12.1°C | 8.2°C | 22.4°C | 4.0°C | 89 mm | 82% | 1.4 m/s | 3.4 |
| 2012 | 17.4°C | 13.1°C | 8.9°C | 24.3°C | 3.6°C | 58 mm | 80% | 1.5 m/s | 3.8 |
| 2011 | 17.5°C | 13.5°C | 9.6°C | 21.6°C | 5.5°C | 103 mm | 84% | 1.3 m/s | 3.8 |
| 2010 🌧️ | 15.5°C | 12.4°C | 9.2°C | 28.9°C | 4.4°C | 210 mm | 84% | 1.4 m/s | 3 |
| 2009 | 16.8°C | 12.5°C | 8.2°C | 23.0°C | 1.8°C | 61 mm | 80% | 1.4 m/s | 4 |
| 2008 | 16.3°C | 12.5°C | 8.6°C | 23.8°C | 1.3°C | 109 mm | 84% | 1.3 m/s | 3.5 |
| 2007 | 16.4°C | 12.2°C | 8.0°C | 26.3°C | 3.1°C | 110 mm | 80% | 1.6 m/s | 3.8 |
| 2006 | 16.7°C | 12.5°C | 8.2°C | 23.3°C | 4.5°C | 113 mm | 80% | 1.4 m/s | 3.6 |
| 2005 | 17.1°C | 13.1°C | 9.2°C | 23.3°C | 4.9°C | 137 mm | 83% | 1.5 m/s | 3.5 |
| 2004 | 15.9°C | 11.9°C | 8.0°C | 21.4°C | 4.2°C | 134 mm | 85% | 1.4 m/s | 3.9 |
| 2003 | 18.8°C | 14.4°C | 9.9°C | 26.1°C | 5.3°C | 78 mm | 79% | 1.3 m/s | 3.9 |
| 2002 | 18.4°C | 13.9°C | 9.4°C | 28.5°C | 3.7°C | 92 mm | 78% | 1.4 m/s | 3.8 |
| 2001 | 17.4°C | 13.3°C | 9.3°C | 26.4°C | 3.6°C | 75 mm | 79% | 1.4 m/s | 3.9 |
| 2000 | 15.5°C | 11.6°C | 7.7°C | 21.0°C | -0.8°C | 67 mm | 79% | 1.7 m/s | 3.6 |
| 1999 | 19.6°C | 15.5°C | 11.4°C | 29.1°C | 6.0°C | 122 mm | 80% | 1.4 m/s | 3.7 |
| 1998 | 16.4°C | 12.7°C | 8.9°C | 20.9°C | 3.6°C | 99 mm | 80% | 1.5 m/s | 3.3 |
| 1997 | 16.4°C | 12.3°C | 8.2°C | 23.2°C | 2.3°C | 39 mm | 79% | 1.5 m/s | 2.9 |
| 1996 | 16.4°C | 12.3°C | 8.2°C | 25.5°C | 2.6°C | 75 mm | 80% | 1.4 m/s | 3.6 |
| 1995 | 15.6°C | 10.9°C | 6.2°C | 21.6°C | 1.3°C | 50 mm | 74% | 1.6 m/s | 3.9 |
| 1994 | 15.5°C | 11.5°C | 7.4°C | 20.8°C | 3.6°C | 69 mm | 82% | 1.3 m/s | 3.5 |
| 1993 | 15.4°C | 11.3°C | 7.2°C | 22.5°C | 0.9°C | 133 mm | 80% | 1.5 m/s | 3.4 |
| 1992 | 16.9°C | 12.4°C | 8.0°C | 23.0°C | 1.1°C | 72 mm | 80% | 1.6 m/s | 3.5 |
| 1991 | 14.9°C | 10.7°C | 6.4°C | 21.5°C | 0.4°C | 56 mm | 77% | 1.6 m/s | 3.6 |
| 1990 | 15.7°C | 11.4°C | 7.1°C | 21.8°C | 2.0°C | 106 mm | 77% | 1.6 m/s | 3.3 |
| 1989 | 17.0°C | 12.4°C | 7.9°C | 24.6°C | 0.7°C | 48 mm | 77% | 1.6 m/s | 3.8 |
| 1988 | 15.0°C | 11.0°C | 7.1°C | 21.7°C | 2.6°C | 78 mm | 78% | 1.8 m/s | 3.5 |
| 1987 | 15.0°C | 11.3°C | 7.7°C | 23.9°C | 1.4°C | 95 mm | 83% | 1.5 m/s | 3.4 |
| 1986 ❄️ | 13.5°C | 9.5°C | 5.5°C | 20.0°C | 0.9°C | 93 mm | 80% | 1.5 m/s | 3.5 |
| 1985 | 17.0°C | 12.6°C | 8.3°C | 24.4°C | 4.3°C | 50 mm | 78% | 1.3 m/s | 3.7 |
| 1984 | 14.3°C | 10.2°C | 6.2°C | 21.1°C | 1.6°C | 26 mm | 78% | 1.6 m/s | 3.7 |
| 1983 | 16.9°C | 12.6°C | 8.4°C | 25.6°C | 3.1°C | 67 mm | 81% | 1.3 m/s | — |
| 1982 | 15.4°C | 11.4°C | 7.3°C | 24.5°C | 1.5°C | 88 mm | 83% | 1.2 m/s | — |
| 1981 | 15.5°C | 11.7°C | 7.8°C | 23.4°C | 3.7°C | 52 mm | 82% | 1.6 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 16.7°C with lows near 8.4°C (mean 12.6°C), based on 45 years of NASA POWER data.
September averages 80 mm of rainfall in Rivière-du-Loup, about average for rainfall. The wettest on record was 210 mm in 2010.
The hottest September reached 29.1°C in 1999. The coldest dipped to -0.8°C in 2000.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.5°C. Daytime highs moved from 15.8°C to 18.7°C and overnight lows from 7.6°C to 9.7°C over the same span.
September is one of the warmer months of the year in Rivière-du-Loup and about average for rainfall, so plan for around 16.7°C daytime highs and 8.4°C at night.
Not quite — September is the 9th coolest month in Rivière-du-Loup, averaging 12.6°C.
For September in Rivière-du-Loup, pack light layers you can adjust through the day, with typical highs of 16.7°C and lows of 8.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 80% — quite humid.
Average wind speed in September is 1.4 m/s. The windiest September on record averaged 1.8 m/s (1988).
The wettest September on record was 2010 with 210 mm. On average, September sees 80 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 Rivière-du-Loup 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.
