September is one of the warmer months of the year in Thompson, with average highs near 13.8°C and lows around 4.1°C (mean 9°C). It is a relatively wet time of year, averaging 64 mm of rainfall and 82% relative humidity across the period.
September is one of the warmer months of the year in Thompson. Across 45 years of records, the warmest Septembers in Thompson were 2023 and 2024 — when the month averaged 13.1°C — while the coldest was 2018 at 4.4°C. Typical September days reach 13.8°C with nights near 4.1°C. The long-term trend is warming, about 0.7°C per decade.
September is a relatively wet time of year in Thompson, averaging 64 mm of rainfall. The wettest September on record was 1983 with 124 mm, while the driest was 1990 at 20 mm.
Relative humidity in Thompson during September averages 82%. The most humid September was 2007 at 87%, and the least humid was 1994 at 75%.
September receives about 2.9 kWh/m²/day of solar energy in Thompson. The sunniest September was 2011 at 3.7 kWh/m²/day, and the cloudiest was 2007 at 2.4.
Average wind speed in Thompson during September is 0.4 m/s. The windiest Septembers were 2023, 2024 and 2025, among others at 0.4 m/s, while the calmest were 2023, 2024 and 2025, among others at 0.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 7.7°C | 8.5°C | 9.0°C | 9.1°C | 11.2°C | +3.5°C |
| Avg High | 12.4°C | 13.6°C | 13.7°C | 14.0°C | 15.9°C | +3.5°C |
| Avg Low | 3.2°C | 3.3°C | 4.3°C | 4.2°C | 6.5°C | +3.3°C |
| Avg Rain | 67 mm | 56 mm | 69 mm | 65 mm | 60 mm | -7 mm |
September temperatures in Thompson have risen by about 4.7°C between 1981–1985 and 2021–2025.
September has ranged from a record low of -7.5°C (1984) to a record high of 28.9°C (2013).
Rainfall in September is a relatively wet time of year, averaging 64 mm, with a wettest year of 124 mm.
One of the best times to visit Thompson
September is one of the best times to visit Thompson. Expect days averaging 13.8°C and nights around 4.1°C (mean 9°C) — warmer than Thompson's yearly average — with moderate rainfall (64 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 | 17.6°C | 12.3°C | 7.0°C | 23.6°C | 2.0°C | 65 mm | 81% | 0.4 m/s | 3.1 |
| 2024 | 18.4°C | 13.1°C | 7.9°C | 26.3°C | 2.0°C | 71 mm | 84% | 0.4 m/s | 3.1 |
| 2023 🔥 | 17.6°C | 13.1°C | 8.5°C | 25.3°C | 4.2°C | 61 mm | 86% | 0.4 m/s | 2.9 |
| 2022 | 15.5°C | 10.8°C | 6.0°C | 25.2°C | -0.7°C | 44 mm | 81% | 0.4 m/s | 3.3 |
| 2021 | 15.4°C | 11.2°C | 7.0°C | 22.1°C | 2.9°C | 51 mm | 86% | 0.4 m/s | 2.6 |
| 2020 | 11.1°C | 6.9°C | 2.7°C | 19.8°C | -4.2°C | 71 mm | 85% | 0.4 m/s | 2.8 |
| 2019 | 14.1°C | 9.0°C | 4.0°C | 23.7°C | -3.4°C | 49 mm | 80% | 0.4 m/s | 3.1 |
| 2018 ❄️ | 8.9°C | 4.4°C | -0.2°C | 17.6°C | -5.7°C | 73 mm | 80% | 0.4 m/s | 2.8 |
| 2017 | 14.7°C | 10.0°C | 5.2°C | 24.3°C | -0.9°C | 68 mm | 81% | 0.4 m/s | 2.9 |
| 2016 | 15.3°C | 10.6°C | 5.8°C | 28.0°C | -0.4°C | 95 mm | 81% | 0.4 m/s | 2.8 |
| 2015 | 14.0°C | 9.3°C | 4.6°C | 25.9°C | -5.7°C | 113 mm | 84% | 0.4 m/s | 2.7 |
| 2014 | 13.0°C | 7.8°C | 2.6°C | 23.8°C | -4.4°C | 32 mm | 82% | 0.4 m/s | 3 |
| 2013 | 17.3°C | 11.8°C | 6.2°C | 28.9°C | -1.5°C | 68 mm | 78% | 0.4 m/s | 3.5 |
| 2012 | 14.6°C | 9.4°C | 4.3°C | 24.7°C | -2.0°C | 51 mm | 80% | 0.4 m/s | 3.2 |
| 2011 | 17.0°C | 11.7°C | 6.4°C | 25.7°C | 0.5°C | 32 mm | 81% | 0.4 m/s | 3.7 |
| 2010 | 11.0°C | 6.8°C | 2.7°C | 17.2°C | -0.7°C | 69 mm | 86% | 0.4 m/s | 2.7 |
| 2009 | 17.8°C | 12.7°C | 7.7°C | 24.0°C | -1.7°C | 41 mm | 84% | 0.4 m/s | 3.2 |
| 2008 | 12.1°C | 7.4°C | 2.8°C | 18.5°C | -4.2°C | 54 mm | 84% | 0.4 m/s | 2.7 |
| 2007 | 10.6°C | 6.4°C | 2.3°C | 20.6°C | -2.1°C | 77 mm | 87% | 0.4 m/s | 2.4 |
| 2006 | 14.1°C | 9.3°C | 4.5°C | 24.1°C | -1.1°C | 25 mm | 83% | 0.4 m/s | 3.5 |
| 2005 | 12.7°C | 8.5°C | 4.3°C | 22.2°C | -2.9°C | 119 mm | 86% | 0.4 m/s | 2.6 |
| 2004 | 14.6°C | 9.8°C | 5.0°C | 20.9°C | -0.5°C | 69 mm | 82% | 0.4 m/s | 2.9 |
| 2003 | 14.4°C | 9.6°C | 4.7°C | 28.0°C | -3.8°C | 67 mm | 79% | 0.4 m/s | 3 |
| 2002 | 13.1°C | 8.7°C | 4.4°C | 23.2°C | -3.7°C | 111 mm | 83% | 0.4 m/s | 2.5 |
| 2001 | 15.5°C | 10.1°C | 4.6°C | 22.0°C | -4.3°C | 53 mm | 80% | 0.4 m/s | 3.2 |
| 2000 | 11.6°C | 7.1°C | 2.6°C | 21.0°C | -5.7°C | 77 mm | 81% | 0.4 m/s | 2.8 |
| 1999 | 12.5°C | 7.9°C | 3.2°C | 20.9°C | -3.2°C | 77 mm | 80% | 0.4 m/s | 2.8 |
| 1998 | 14.9°C | 9.6°C | 4.4°C | 23.5°C | -0.7°C | 31 mm | 80% | 0.4 m/s | 3 |
| 1997 | 14.4°C | 9.8°C | 5.2°C | 22.1°C | -2.3°C | 102 mm | 85% | 0.4 m/s | 3 |
| 1996 | 15.1°C | 9.9°C | 4.8°C | 27.5°C | -4.7°C | 55 mm | 78% | 0.4 m/s | 3.4 |
| 1995 | 13.5°C | 8.4°C | 3.2°C | 24.6°C | -4.0°C | 31 mm | 79% | 0.4 m/s | 3.3 |
| 1994 | 17.9°C | 11.9°C | 5.9°C | 26.4°C | -1.3°C | 39 mm | 75% | 0.4 m/s | 3 |
| 1993 | 10.2°C | 5.1°C | 0.0°C | 18.7°C | -3.4°C | 56 mm | 79% | 0.4 m/s | 3.1 |
| 1992 | 11.3°C | 6.3°C | 1.4°C | 17.8°C | -5.8°C | 106 mm | 79% | 0.4 m/s | 2.8 |
| 1991 | 12.1°C | 7.3°C | 2.5°C | 26.5°C | -5.2°C | 45 mm | 78% | 0.4 m/s | 3 |
| 1990 | 14.1°C | 8.4°C | 2.8°C | 22.7°C | -2.4°C | 20 mm | 75% | 0.4 m/s | 3 |
| 1989 | 12.6°C | 8.3°C | 4.0°C | 23.0°C | -2.3°C | 78 mm | 82% | 0.4 m/s | 2.6 |
| 1988 | 13.4°C | 8.8°C | 4.3°C | 24.7°C | -2.6°C | 55 mm | 81% | 0.4 m/s | 2.6 |
| 1987 | 13.6°C | 9.3°C | 5.1°C | 18.5°C | -0.5°C | 68 mm | 86% | 0.4 m/s | 2.9 |
| 1986 | 10.7°C | 6.3°C | 1.8°C | 17.3°C | -2.9°C | 47 mm | 83% | 0.4 m/s | 2.8 |
| 1985 | 11.5°C | 6.5°C | 1.6°C | 19.8°C | -3.5°C | 44 mm | 79% | 0.4 m/s | 2.9 |
| 1984 | 10.0°C | 5.5°C | 1.0°C | 20.1°C | -7.5°C | 73 mm | 82% | 0.4 m/s | 2.6 |
| 1983 🌧️ | 13.5°C | 9.2°C | 4.9°C | 26.7°C | -3.7°C | 124 mm | 84% | 0.4 m/s | — |
| 1982 | 12.5°C | 7.8°C | 3.1°C | 20.3°C | -4.5°C | 65 mm | 81% | 0.4 m/s | — |
| 1981 | 13.5°C | 8.0°C | 2.6°C | 25.4°C | -5.7°C | 54 mm | 77% | 0.4 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 13.8°C with lows near 4.1°C (mean 9°C), based on 45 years of NASA POWER data.
September averages 64 mm of rainfall in Thompson, a relatively wet time of year. The wettest on record was 124 mm in 1983.
The hottest September reached 28.9°C in 2013. The coldest dipped to -7.5°C in 1984.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 4.7°C. Daytime highs moved from 12.2°C to 16.9°C and overnight lows from 2.6°C to 7.3°C over the same span.
September is one of the warmer months of the year in Thompson and a relatively wet time of year, so plan for around 13.8°C daytime highs and 4.1°C at night.
Not quite — September is the 9th coolest month in Thompson, averaging 9°C.
For September in Thompson, pack warm layers and a jacket for chilly mornings, with typical highs of 13.8°C and lows of 4.1°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 82% — quite humid.
Average wind speed in September is 0.4 m/s. The windiest September on record averaged 0.4 m/s (1981).
The wettest September on record was 1983 with 124 mm. On average, September sees 64 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 Thompson 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.
