September is one of the warmer months of the year in Corner Brook, with average highs near 15.1°C and lows around 8.6°C (mean 11.9°C). It is about average for rainfall, averaging 118 mm of rainfall and 85% relative humidity across the period.
September is one of the warmer months of the year in Corner Brook. Across 45 years of records, the warmest September in Corner Brook was 2012 — when the month averaged 14.4°C — while the coldest was 1986 at 8.9°C. Typical September days reach 15.1°C with nights near 8.6°C. The long-term trend is warming, about 0.5°C per decade.
September is about average for rainfall in Corner Brook, averaging 118 mm of rainfall. The wettest September on record was 1998 with 206 mm, while the driest was 2024 at 36 mm.
Relative humidity in Corner Brook during September averages 85%. The most humid September was 1998 at 89%, and the least humid was 2014 at 82%.
September receives about 3.3 kWh/m²/day of solar energy in Corner Brook. The sunniest September was 2025 at 3.9 kWh/m²/day, and the cloudiest were 1991 and 2023 at 2.9.
Average wind speed in Corner Brook during September is 1.6 m/s. The windiest Septembers were 1988, 2014 and 2018, among others at 1.8 m/s, while the calmest was 1991 at 1.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 11.0°C | 11.5°C | 11.8°C | 12.2°C | 13.3°C | +2.3°C |
| Avg High | 14.2°C | 14.8°C | 15.0°C | 15.3°C | 16.6°C | +2.4°C |
| Avg Low | 7.7°C | 8.2°C | 8.6°C | 9.0°C | 9.9°C | +2.2°C |
| Avg Rain | 109 mm | 126 mm | 126 mm | 126 mm | 92 mm | -17 mm |
September temperatures in Corner Brook have risen by about 2.1°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 0.3°C (1986) to a record high of 25°C (2008).
Rainfall in September is about average for rainfall, averaging 118 mm, with a wettest year of 206 mm.
One of the best times to visit Corner Brook
September is one of the best times to visit Corner Brook. Expect days averaging 15.1°C and nights around 8.6°C (mean 11.9°C) — warmer than Corner Brook's yearly average — with higher rainfall (118 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 | 12.7°C | 9.5°C | 21.9°C | 4.5°C | 67 mm | 84% | 1.6 m/s | 3.9 |
| 2024 | 16.5°C | 13.2°C | 9.9°C | 21.9°C | 5.3°C | 36 mm | 85% | 1.4 m/s | 3.4 |
| 2023 | 17.7°C | 14.2°C | 10.7°C | 24.9°C | 4.7°C | 74 mm | 87% | 1.4 m/s | 2.9 |
| 2022 | 17.1°C | 13.6°C | 10.1°C | 23.9°C | 6.0°C | 104 mm | 84% | 1.6 m/s | 3.5 |
| 2021 | 16.8°C | 13.5°C | 10.2°C | 22.9°C | 4.8°C | 199 mm | 87% | 1.6 m/s | 3.1 |
| 2020 | 15.6°C | 12.4°C | 9.2°C | 21.9°C | 4.0°C | 69 mm | 83% | 1.7 m/s | 3.5 |
| 2019 | 13.3°C | 10.2°C | 7.2°C | 19.0°C | 3.3°C | 135 mm | 86% | 1.7 m/s | 3.3 |
| 2018 | 14.4°C | 11.0°C | 7.6°C | 22.3°C | 1.9°C | 138 mm | 82% | 1.8 m/s | 3.7 |
| 2017 | 15.4°C | 12.2°C | 9.1°C | 22.1°C | 3.2°C | 158 mm | 86% | 1.5 m/s | 3 |
| 2016 | 14.5°C | 11.4°C | 8.2°C | 22.3°C | 2.8°C | 119 mm | 86% | 1.6 m/s | 3.3 |
| 2015 | 16.1°C | 12.9°C | 9.7°C | 21.5°C | 3.9°C | 92 mm | 85% | 1.6 m/s | 3.2 |
| 2014 | 15.2°C | 11.9°C | 8.5°C | 22.0°C | 2.4°C | 78 mm | 82% | 1.8 m/s | 3.7 |
| 2013 | 15.7°C | 13.0°C | 10.2°C | 21.3°C | 3.7°C | 146 mm | 88% | 1.6 m/s | 3.1 |
| 2012 🔥 | 17.7°C | 14.4°C | 11.1°C | 21.9°C | 6.5°C | 176 mm | 86% | 1.5 m/s | 3.2 |
| 2011 | 15.5°C | 12.2°C | 9.0°C | 20.2°C | 4.7°C | 79 mm | 86% | 1.6 m/s | 3.5 |
| 2010 | 15.2°C | 12.3°C | 9.3°C | 23.6°C | 2.8°C | 136 mm | 85% | 1.6 m/s | 3 |
| 2009 | 14.0°C | 10.9°C | 7.8°C | 20.3°C | 0.8°C | 75 mm | 86% | 1.5 m/s | 3.6 |
| 2008 | 15.9°C | 12.8°C | 9.7°C | 25.0°C | 1.8°C | 92 mm | 84% | 1.6 m/s | 3.2 |
| 2007 | 14.4°C | 11.1°C | 7.8°C | 21.9°C | 4.3°C | 139 mm | 85% | 1.7 m/s | 3.2 |
| 2006 | 15.4°C | 12.2°C | 8.9°C | 20.4°C | 5.3°C | 81 mm | 86% | 1.6 m/s | 3.3 |
| 2005 | 15.0°C | 11.7°C | 8.5°C | 23.1°C | 4.0°C | 201 mm | 87% | 1.6 m/s | 3.1 |
| 2004 | 13.3°C | 10.4°C | 7.5°C | 18.9°C | 3.2°C | 174 mm | 85% | 1.6 m/s | 3.3 |
| 2003 | 17.3°C | 13.8°C | 10.3°C | 23.1°C | 5.5°C | 70 mm | 87% | 1.4 m/s | 3.7 |
| 2002 | 14.3°C | 11.0°C | 7.6°C | 20.6°C | 3.1°C | 203 mm | 86% | 1.5 m/s | 3.4 |
| 2001 | 15.7°C | 12.5°C | 9.3°C | 23.5°C | 3.7°C | 135 mm | 87% | 1.4 m/s | 3.7 |
| 2000 | 14.7°C | 11.6°C | 8.4°C | 22.1°C | 2.3°C | 92 mm | 82% | 1.7 m/s | 3.3 |
| 1999 | 17.8°C | 14.0°C | 10.2°C | 22.7°C | 5.7°C | 158 mm | 87% | 1.4 m/s | 3.3 |
| 1998 🌧️ | 14.4°C | 11.4°C | 8.4°C | 19.8°C | 4.2°C | 206 mm | 89% | 1.4 m/s | 3 |
| 1997 | 15.1°C | 12.1°C | 9.1°C | 19.0°C | 2.8°C | 121 mm | 87% | 1.4 m/s | 3.1 |
| 1996 | 13.8°C | 10.3°C | 6.9°C | 20.7°C | 2.2°C | 109 mm | 84% | 1.5 m/s | 3.5 |
| 1995 | 14.0°C | 10.6°C | 7.3°C | 17.8°C | 2.9°C | 87 mm | 84% | 1.5 m/s | 3.6 |
| 1994 | 14.4°C | 11.0°C | 7.6°C | 19.8°C | 3.5°C | 122 mm | 87% | 1.4 m/s | 3.3 |
| 1993 | 14.8°C | 11.5°C | 8.2°C | 20.2°C | 3.5°C | 128 mm | 85% | 1.6 m/s | 3.1 |
| 1992 | 15.3°C | 12.0°C | 8.8°C | 20.9°C | 3.3°C | 79 mm | 85% | 1.4 m/s | 3.3 |
| 1991 | 13.1°C | 10.2°C | 7.3°C | 18.9°C | 3.6°C | 155 mm | 87% | 1.3 m/s | 2.9 |
| 1990 | 15.2°C | 11.5°C | 7.9°C | 18.9°C | 3.6°C | 97 mm | 84% | 1.6 m/s | 3.4 |
| 1989 | 15.0°C | 11.5°C | 8.0°C | 23.8°C | 1.4°C | 112 mm | 85% | 1.6 m/s | 3.6 |
| 1988 | 13.4°C | 10.7°C | 7.9°C | 19.1°C | 3.4°C | 132 mm | 84% | 1.8 m/s | 3.2 |
| 1987 | 14.0°C | 10.9°C | 7.7°C | 19.6°C | 3.5°C | 123 mm | 85% | 1.6 m/s | 3.3 |
| 1986 ❄️ | 12.3°C | 8.9°C | 5.4°C | 18.3°C | 0.3°C | 84 mm | 82% | 1.6 m/s | 3.4 |
| 1985 | 14.2°C | 10.9°C | 7.6°C | 19.2°C | 4.2°C | 86 mm | 85% | 1.4 m/s | 3.6 |
| 1984 | 13.6°C | 10.4°C | 7.2°C | 20.6°C | 3.6°C | 129 mm | 83% | 1.8 m/s | 3.4 |
| 1983 | 14.9°C | 11.8°C | 8.7°C | 23.0°C | 4.5°C | 96 mm | 86% | 1.5 m/s | — |
| 1982 | 14.2°C | 10.9°C | 7.5°C | 19.7°C | 1.6°C | 99 mm | 86% | 1.4 m/s | — |
| 1981 | 15.8°C | 12.6°C | 9.3°C | 24.2°C | 5.0°C | 117 mm | 85% | 1.5 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 15.1°C with lows near 8.6°C (mean 11.9°C), based on 45 years of NASA POWER data.
September averages 118 mm of rainfall in Corner Brook, about average for rainfall. The wettest on record was 206 mm in 1998.
The hottest September reached 25°C in 2008. The coldest dipped to 0.3°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.1°C. Daytime highs moved from 14.5°C to 16.8°C and overnight lows from 8.1°C to 10.1°C over the same span.
September is one of the warmer months of the year in Corner Brook and about average for rainfall, so plan for around 15.1°C daytime highs and 8.6°C at night.
Not quite — September is the 10th coolest month in Corner Brook, averaging 11.9°C.
For September in Corner Brook, pack light layers you can adjust through the day, with typical highs of 15.1°C and lows of 8.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 85% — quite humid.
Average wind speed in September is 1.6 m/s. The windiest September on record averaged 1.8 m/s (1984).
The wettest September on record was 1998 with 206 mm. On average, September sees 118 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 Corner Brook 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.
