September is one of the warmer months of the year in Coquitlam, with average highs near 16.7°C and lows around 7.7°C (mean 12.2°C). It is one of the drier months, averaging 116 mm of rainfall and 81% relative humidity across the period.
September is one of the warmer months of the year in Coquitlam. Across 45 years of records, the warmest September in Coquitlam was 2025 — when the month averaged 14.5°C — while the coldest were 1983 and 1984 at 9.5°C. Typical September days reach 16.7°C with nights near 7.7°C. The long-term trend is warming, about 0.3°C per decade.
September is one of the drier months in Coquitlam, averaging 116 mm of rainfall. The wettest September on record was 2021 with 284 mm, while the driest was 1991 at 12 mm.
Relative humidity in Coquitlam during September averages 81%. The most humid September was 2010 at 88%, and the least humid was 1993 at 73%.
September receives about 3.7 kWh/m²/day of solar energy in Coquitlam. The sunniest September was 1993 at 4.6 kWh/m²/day, and the cloudiest was 2019 at 3.
Average wind speed in Coquitlam during September is 0.4 m/s. The windiest Septembers were 1993, 1995 and 1999, among others at 0.5 m/s, while the calmest was 2025 at 0.3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 11.3°C | 12.7°C | 11.8°C | 12.3°C | 13.2°C | +1.9°C |
| Avg High | 16.0°C | 17.5°C | 16.1°C | 16.5°C | 17.5°C | +1.5°C |
| Avg Low | 6.6°C | 7.8°C | 7.5°C | 8.0°C | 8.9°C | +2.3°C |
| Avg Rain | 103 mm | 82 mm | 106 mm | 156 mm | 145 mm | +42 mm |
September temperatures in Coquitlam have risen by about 2.5°C between 1981–1985 and 2021–2025.
September has ranged from a record low of -1.4°C (1983) to a record high of 33.2°C (1988).
Rainfall in September is one of the drier months, averaging 116 mm, with a wettest year of 284 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0.1°C per decade while lows rose 0.5°C per decade, narrowing the gap between day and night.
One of the best times to visit Coquitlam
September is one of the best times to visit Coquitlam. Expect days averaging 16.7°C and nights around 7.7°C (mean 12.2°C) — warmer than Coquitlam's yearly average — with higher rainfall (116 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 🔥 | 18.7°C | 14.5°C | 10.4°C | 29.5°C | 6.0°C | 152 mm | 87% | 0.3 m/s | 3.7 |
| 2024 | 16.8°C | 12.6°C | 8.4°C | 31.8°C | -0.5°C | 122 mm | 86% | 0.4 m/s | 3.5 |
| 2023 | 16.3°C | 12.1°C | 7.8°C | 24.2°C | 1.6°C | 115 mm | 82% | 0.4 m/s | 3.6 |
| 2022 | 19.4°C | 14.3°C | 9.2°C | 27.6°C | 4.5°C | 24 mm | 78% | 0.4 m/s | 4.2 |
| 2021 🌧️ | 15.1°C | 11.5°C | 7.9°C | 26.9°C | 3.5°C | 284 mm | 87% | 0.4 m/s | 3.1 |
| 2020 | 18.8°C | 14.3°C | 9.8°C | 27.1°C | 5.2°C | 170 mm | 84% | 0.4 m/s | 3.5 |
| 2019 | 15.1°C | 11.7°C | 8.3°C | 26.7°C | -0.8°C | 215 mm | 86% | 0.4 m/s | 3 |
| 2018 | 14.3°C | 10.8°C | 7.3°C | 22.8°C | 3.6°C | 225 mm | 86% | 0.4 m/s | 3.2 |
| 2017 | 17.6°C | 13.2°C | 8.8°C | 26.3°C | 1.7°C | 70 mm | 79% | 0.4 m/s | 3.6 |
| 2016 | 14.8°C | 10.9°C | 6.9°C | 21.5°C | 2.9°C | 101 mm | 84% | 0.4 m/s | 3.6 |
| 2015 | 14.8°C | 10.7°C | 6.6°C | 26.6°C | 2.3°C | 156 mm | 83% | 0.4 m/s | 3.4 |
| 2014 | 18.3°C | 13.4°C | 8.5°C | 28.2°C | 2.5°C | 117 mm | 79% | 0.4 m/s | 3.8 |
| 2013 | 17.3°C | 13.2°C | 9.1°C | 26.8°C | 1.2°C | 257 mm | 85% | 0.4 m/s | 3.3 |
| 2012 | 19.4°C | 13.9°C | 8.3°C | 31.0°C | 2.3°C | 21 mm | 75% | 0.4 m/s | 4.3 |
| 2011 | 18.4°C | 13.8°C | 9.2°C | 30.9°C | 4.2°C | 153 mm | 77% | 0.4 m/s | 3.6 |
| 2010 | 14.8°C | 11.1°C | 7.4°C | 21.8°C | 1.1°C | 242 mm | 88% | 0.4 m/s | 3.2 |
| 2009 | 17.5°C | 13.0°C | 8.5°C | 30.3°C | 2.4°C | 131 mm | 80% | 0.4 m/s | 3.7 |
| 2008 | 17.4°C | 12.3°C | 7.2°C | 28.1°C | 3.9°C | 43 mm | 78% | 0.4 m/s | 3.9 |
| 2007 | 14.6°C | 10.9°C | 7.1°C | 26.9°C | 1.1°C | 112 mm | 85% | 0.4 m/s | 3.5 |
| 2006 | 18.0°C | 13.3°C | 8.6°C | 29.3°C | 2.7°C | 72 mm | 79% | 0.4 m/s | 4.2 |
| 2005 | 14.2°C | 10.4°C | 6.6°C | 20.9°C | 1.2°C | 115 mm | 84% | 0.4 m/s | 3.6 |
| 2004 | 13.9°C | 10.4°C | 6.9°C | 21.0°C | 3.4°C | 169 mm | 88% | 0.4 m/s | 3.1 |
| 2003 | 17.8°C | 13.0°C | 8.2°C | 28.7°C | 4.2°C | 80 mm | 80% | 0.4 m/s | 4 |
| 2002 | 16.1°C | 11.4°C | 6.7°C | 23.8°C | 2.0°C | 104 mm | 80% | 0.4 m/s | 3.8 |
| 2001 | 16.4°C | 12.1°C | 7.9°C | 26.7°C | 5.0°C | 84 mm | 81% | 0.4 m/s | 3.8 |
| 2000 | 15.3°C | 11.1°C | 7.0°C | 24.2°C | -0.6°C | 144 mm | 82% | 0.4 m/s | 3.6 |
| 1999 | 16.9°C | 11.7°C | 6.4°C | 23.5°C | 1.4°C | 64 mm | 75% | 0.5 m/s | 4.2 |
| 1998 | 18.7°C | 13.9°C | 9.1°C | 24.4°C | 4.0°C | 27 mm | 78% | 0.4 m/s | 4.2 |
| 1997 | 17.5°C | 13.0°C | 8.5°C | 26.9°C | 1.6°C | 225 mm | 81% | 0.4 m/s | 3.6 |
| 1996 | 14.1°C | 10.3°C | 6.4°C | 24.6°C | 0.1°C | 144 mm | 84% | 0.4 m/s | 3.2 |
| 1995 | 19.6°C | 14.0°C | 8.4°C | 28.3°C | 3.5°C | 56 mm | 75% | 0.5 m/s | 4.2 |
| 1994 | 17.9°C | 13.4°C | 9.0°C | 24.6°C | 4.2°C | 95 mm | 81% | 0.4 m/s | 3.7 |
| 1993 | 18.7°C | 13.3°C | 7.9°C | 27.6°C | 2.0°C | 17 mm | 73% | 0.5 m/s | 4.6 |
| 1992 | 13.7°C | 9.6°C | 5.4°C | 21.6°C | -0.9°C | 142 mm | 83% | 0.4 m/s | 3.5 |
| 1991 | 18.6°C | 13.4°C | 8.3°C | 24.6°C | 4.7°C | 12 mm | 77% | 0.4 m/s | 4.3 |
| 1990 | 19.5°C | 14.2°C | 8.8°C | 24.9°C | 4.9°C | 39 mm | 75% | 0.5 m/s | 4.1 |
| 1989 | 18.8°C | 13.3°C | 7.7°C | 25.3°C | 4.2°C | 26 mm | 75% | 0.5 m/s | 4.4 |
| 1988 | 16.5°C | 11.5°C | 6.6°C | 33.2°C | 1.4°C | 133 mm | 80% | 0.4 m/s | 3.6 |
| 1987 | 19.2°C | 13.9°C | 8.6°C | 29.1°C | 4.0°C | 45 mm | 75% | 0.4 m/s | 3.9 |
| 1986 | 14.3°C | 10.1°C | 6.0°C | 22.6°C | -0.3°C | 114 mm | 83% | 0.4 m/s | 3.6 |
| 1985 | 14.2°C | 9.6°C | 5.0°C | 19.3°C | 0.0°C | 105 mm | 80% | 0.4 m/s | 3.6 |
| 1984 | 13.9°C | 9.5°C | 5.2°C | 19.8°C | -0.1°C | 148 mm | 81% | 0.4 m/s | 3.4 |
| 1983 ❄️ | 13.9°C | 9.5°C | 5.2°C | 19.9°C | -1.4°C | 113 mm | 81% | 0.4 m/s | — |
| 1982 | 16.8°C | 12.2°C | 7.6°C | 24.3°C | 1.3°C | 92 mm | 81% | 0.4 m/s | — |
| 1981 | 16.4°C | 11.9°C | 7.5°C | 30.5°C | 1.8°C | 151 mm | 81% | 0.4 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 7.7°C (mean 12.2°C), based on 45 years of NASA POWER data.
September averages 116 mm of rainfall in Coquitlam, one of the drier months. The wettest on record was 284 mm in 2021.
The hottest September reached 33.2°C in 1988. The coldest dipped to -1.4°C in 1983.
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°C to 17.3°C and overnight lows from 6.1°C to 8.7°C over the same span.
September is one of the warmer months of the year in Coquitlam and one of the drier months, so plan for around 16.7°C daytime highs and 7.7°C at night.
Not quite — September is the 10th coolest month in Coquitlam, averaging 12.2°C.
For September in Coquitlam, pack warm layers and a jacket for chilly mornings, with typical highs of 16.7°C and lows of 7.7°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 81% — quite humid.
Average wind speed in September is 0.4 m/s. The windiest September on record averaged 0.5 m/s (1989).
The wettest September on record was 2021 with 284 mm. On average, September sees 116 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 Coquitlam 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.
