September is one of the warmer months of the year in Brunswick, with average highs near 28°C and lows around 25.4°C (mean 26.7°C). It is a relatively wet time of year, averaging 146 mm of rainfall and 78% relative humidity across the period.
September is one of the warmer months of the year in Brunswick. Across 45 years of records, the warmest September in Brunswick was 2018 — when the month averaged 28.3°C — while the coldest was 1984 at 25.3°C. Typical September days reach 28°C with nights near 25.4°C. The long-term trend is warming, about 0.2°C per decade.
September is a relatively wet time of year in Brunswick, averaging 146 mm of rainfall. The wettest September on record was 1988 with 328 mm, while the driest was 2025 at 41 mm.
Relative humidity in Brunswick during September averages 78%. The most humid September was 2024 at 85%, and the least humid was 1981 at 69%.
September receives about 4.8 kWh/m²/day of solar energy in Brunswick. The sunniest September was 2019 at 5.5 kWh/m²/day, and the cloudiest were 1988, 2004 and 2024 at 4.
Average wind speed in Brunswick during September is 3.7 m/s. The windiest September was 2004 at 5.4 m/s, while the calmest were 1981 and 1987 at 3 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 26.3°C | 26.7°C | 26.5°C | 27.0°C | 26.8°C | +0.5°C |
| Avg High | 27.6°C | 28.0°C | 27.7°C | 28.4°C | 28.1°C | +0.5°C |
| Avg Low | 25.1°C | 25.4°C | 25.3°C | 25.7°C | 25.5°C | +0.4°C |
| Avg Rain | 187 mm | 134 mm | 160 mm | 117 mm | 129 mm | -58 mm |
September temperatures in Brunswick have risen by about 0.8°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 17.7°C (1984) to a record high of 32.4°C (2020).
Rainfall in September is a relatively wet time of year, averaging 146 mm, with a wettest year of 328 mm.
A good time to visit Brunswick
September is a good time to visit Brunswick, with days averaging 28°C and nights around 25.4°C (mean 26.7°C, warmer than Brunswick's yearly average) and higher rainfall. October and April are marginally more temperate, but September still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 27.8°C | 26.5°C | 25.3°C | 30.1°C | 22.9°C | 41 mm | 78% | 3.7 m/s | 5.3 |
| 2024 | 28.0°C | 26.9°C | 25.8°C | 31.3°C | 22.3°C | 171 mm | 85% | 3.9 m/s | 4 |
| 2023 | 28.5°C | 27.0°C | 25.5°C | 31.4°C | 22.1°C | 122 mm | 75% | 3.5 m/s | 5.1 |
| 2022 | 28.3°C | 27.0°C | 25.7°C | 31.1°C | 18.6°C | 127 mm | 78% | 3.8 m/s | 4.7 |
| 2021 | 27.9°C | 26.6°C | 25.4°C | 30.1°C | 21.6°C | 158 mm | 77% | 3.2 m/s | 5.1 |
| 2020 | 28.2°C | 26.9°C | 25.5°C | 32.4°C | 18.4°C | 156 mm | 81% | 3.9 m/s | 4.4 |
| 2019 | 29.2°C | 27.8°C | 26.4°C | 32.0°C | 23.8°C | 48 mm | 75% | 4.3 m/s | 5.5 |
| 2018 🔥 | 29.5°C | 28.3°C | 27.1°C | 31.7°C | 26.0°C | 68 mm | 78% | 3.4 m/s | 5.1 |
| 2017 | 28.1°C | 26.7°C | 25.3°C | 30.6°C | 22.4°C | 209 mm | 80% | 3.8 m/s | 4.7 |
| 2016 | 28.6°C | 27.0°C | 25.4°C | 30.5°C | 23.2°C | 116 mm | 77% | 3.4 m/s | 4.9 |
| 2015 | 27.6°C | 26.4°C | 25.3°C | 30.7°C | 20.9°C | 144 mm | 82% | 3.5 m/s | 4.2 |
| 2014 | 27.8°C | 26.6°C | 25.3°C | 30.7°C | 21.1°C | 196 mm | 81% | 3.2 m/s | 4.1 |
| 2013 | 27.8°C | 26.6°C | 25.5°C | 30.7°C | 22.3°C | 104 mm | 78% | 3.6 m/s | 4.9 |
| 2012 | 27.8°C | 26.5°C | 25.2°C | 29.5°C | 22.0°C | 79 mm | 77% | 3.6 m/s | 5.1 |
| 2011 | 28.5°C | 26.9°C | 25.2°C | 31.0°C | 22.1°C | 121 mm | 76% | 3.2 m/s | 4.9 |
| 2010 | 29.1°C | 27.6°C | 26.0°C | 32.2°C | 22.8°C | 85 mm | 71% | 3.2 m/s | 5.2 |
| 2009 | 27.4°C | 26.4°C | 25.4°C | 29.9°C | 20.5°C | 98 mm | 78% | 3.9 m/s | 4.9 |
| 2008 | 27.5°C | 26.1°C | 24.7°C | 30.5°C | 18.8°C | 104 mm | 80% | 4.1 m/s | 5 |
| 2007 | 28.2°C | 27.1°C | 26.0°C | 30.0°C | 24.7°C | 187 mm | 79% | 4.1 m/s | 5.1 |
| 2006 | 28.2°C | 26.8°C | 25.4°C | 30.4°C | 21.6°C | 97 mm | 74% | 3.3 m/s | 5.2 |
| 2005 | 29.0°C | 27.5°C | 25.9°C | 31.7°C | 22.9°C | 79 mm | 76% | 4.2 m/s | 5.2 |
| 2004 | 27.5°C | 26.5°C | 25.5°C | 29.7°C | 22.4°C | 291 mm | 84% | 5.4 m/s | 4 |
| 2003 | 26.8°C | 25.5°C | 24.3°C | 28.4°C | 20.8°C | 89 mm | 81% | 3.7 m/s | 4.9 |
| 2002 | 28.6°C | 27.5°C | 26.4°C | 31.0°C | 24.6°C | 165 mm | 81% | 4 m/s | 4.7 |
| 2001 | 26.7°C | 25.5°C | 24.3°C | 30.0°C | 19.7°C | 196 mm | 78% | 3.8 m/s | 4.5 |
| 2000 | 27.5°C | 26.3°C | 25.0°C | 30.3°C | 21.4°C | 294 mm | 82% | 4.1 m/s | 4.2 |
| 1999 | 27.9°C | 26.4°C | 24.9°C | 32.3°C | 21.2°C | 191 mm | 76% | 4 m/s | 4.8 |
| 1998 | 28.1°C | 26.9°C | 25.6°C | 30.9°C | 23.8°C | 191 mm | 78% | 3.7 m/s | 4.5 |
| 1997 | 28.8°C | 27.2°C | 25.6°C | 31.6°C | 22.7°C | 143 mm | 74% | 3.5 m/s | 5 |
| 1996 | 28.4°C | 26.8°C | 25.3°C | 30.8°C | 22.7°C | 102 mm | 74% | 3.4 m/s | 4.8 |
| 1995 | 27.1°C | 26.0°C | 25.0°C | 28.9°C | 21.5°C | 142 mm | 83% | 3.7 m/s | 4.1 |
| 1994 | 27.4°C | 25.9°C | 24.4°C | 31.3°C | 21.4°C | 107 mm | 77% | 3.7 m/s | 4.9 |
| 1993 | 28.5°C | 27.2°C | 26.0°C | 31.1°C | 20.7°C | 138 mm | 75% | 3.5 m/s | 4.9 |
| 1992 | 27.5°C | 26.5°C | 25.5°C | 30.7°C | 20.5°C | 224 mm | 81% | 4 m/s | 4.5 |
| 1991 | 27.8°C | 26.7°C | 25.6°C | 30.9°C | 20.3°C | 62 mm | 77% | 4 m/s | 4.8 |
| 1990 | 28.8°C | 27.4°C | 26.0°C | 31.8°C | 21.2°C | 43 mm | 71% | 3.5 m/s | 5.2 |
| 1989 | 27.5°C | 26.5°C | 25.4°C | 30.2°C | 23.3°C | 315 mm | 82% | 3.9 m/s | 4.3 |
| 1988 🌧️ | 27.7°C | 26.7°C | 25.7°C | 30.8°C | 21.9°C | 328 mm | 82% | 3.9 m/s | 4 |
| 1987 | 28.4°C | 27.0°C | 25.6°C | 30.4°C | 23.1°C | 245 mm | 74% | 3 m/s | 4.4 |
| 1986 | 28.1°C | 26.9°C | 25.6°C | 30.2°C | 24.1°C | 69 mm | 77% | 3.2 m/s | 4.9 |
| 1985 | 27.3°C | 26.1°C | 25.0°C | 31.2°C | 22.0°C | 107 mm | 77% | 4.3 m/s | 5.1 |
| 1984 ❄️ | 26.8°C | 25.3°C | 23.8°C | 31.1°C | 17.7°C | 232 mm | 78% | 4.6 m/s | 4.6 |
| 1983 | 27.4°C | 26.1°C | 24.8°C | 32.1°C | 19.8°C | 112 mm | 75% | 3.8 m/s | — |
| 1982 | 27.3°C | 26.2°C | 25.0°C | 30.9°C | 19.9°C | 218 mm | 76% | 3.6 m/s | — |
| 1981 | 27.7°C | 26.2°C | 24.8°C | 30.0°C | 17.9°C | 56 mm | 69% | 3 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 28°C with lows near 25.4°C (mean 26.7°C), based on 45 years of NASA POWER data.
September averages 146 mm of rainfall in Brunswick, a relatively wet time of year. The wettest on record was 328 mm in 1988.
The hottest September reached 32.4°C in 2020. The coldest dipped to 17.7°C in 1984.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 0.8°C. Daytime highs moved from 27.3°C to 28.1°C and overnight lows from 24.7°C to 25.5°C over the same span.
September is one of the warmer months of the year in Brunswick and a relatively wet time of year, so plan for around 28°C daytime highs and 25.4°C at night.
Not quite — September is the 9th coolest month in Brunswick, averaging 26.7°C.
For September in Brunswick, pack light layers you can adjust through the day, with typical highs of 28°C and lows of 25.4°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 78% — quite humid.
Average wind speed in September is 3.7 m/s. The windiest September on record averaged 5.4 m/s (2004).
The wettest September on record was 1988 with 328 mm. On average, September sees 146 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 Brunswick 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.
