September is one of the cooler months of the year in Kiama, with average highs near 17.9°C and lows around 8.2°C (mean 13.1°C). It is one of the drier months, averaging 59 mm of rainfall and 71% relative humidity across the period.
September is one of the cooler months of the year in Kiama. Across 45 years of records, the warmest September in Kiama was 2023 — when the month averaged 16.2°C — while the coldest was 1984 at 10.8°C. Typical September days reach 17.9°C with nights near 8.2°C. The long-term trend is warming, about 0.5°C per decade.
September is one of the drier months in Kiama, averaging 59 mm of rainfall. The wettest September on record was 1995 with 199 mm, while the driest was 2017 at 2 mm.
Relative humidity in Kiama during September averages 71%. The most humid September was 2022 at 83%, and the least humid was 2017 at 51%.
September receives about 4.8 kWh/m²/day of solar energy in Kiama. The sunniest Septembers were 1994, 2017 and 2023 at 5.4 kWh/m²/day, and the cloudiest was 2022 at 4.
Average wind speed in Kiama during September is 0.6 m/s. The windiest Septembers were 2022, 2024 and 2025, among others at 0.6 m/s, while the calmest were 2018, 2020 and 2023, among others at 0.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 12.3°C | 12.3°C | 13.8°C | 13.4°C | 13.9°C | +1.6°C |
| Avg High | 17.0°C | 16.8°C | 18.9°C | 18.3°C | 18.8°C | +1.8°C |
| Avg Low | 7.6°C | 7.8°C | 8.7°C | 8.5°C | 9.0°C | +1.4°C |
| Avg Rain | 67 mm | 80 mm | 48 mm | 45 mm | 50 mm | -17 mm |
September temperatures in Kiama have risen by about 1.7°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 1.8°C (1994) to a record high of 31.8°C (2017).
Rainfall in September is one of the drier months, averaging 59 mm, with a wettest year of 199 mm.
A good time to visit Kiama
September is a good time to visit Kiama, with days averaging 17.9°C and nights around 8.2°C (mean 13.1°C, cooler than Kiama's yearly average) and moderate rainfall. January and December 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 | 18.3°C | 13.6°C | 8.8°C | 23.4°C | 4.6°C | 83 mm | 73% | 0.6 m/s | 5.1 |
| 2024 | 19.7°C | 14.4°C | 9.2°C | 25.2°C | 3.2°C | 24 mm | 59% | 0.6 m/s | 4.9 |
| 2023 🔥 | 22.6°C | 16.2°C | 9.7°C | 31.7°C | 5.1°C | 26 mm | 58% | 0.5 m/s | 5.4 |
| 2022 | 15.5°C | 12.1°C | 8.8°C | 19.0°C | 4.6°C | 114 mm | 83% | 0.6 m/s | 4 |
| 2021 | 19.0°C | 13.7°C | 8.3°C | 24.1°C | 5.1°C | 34 mm | 66% | 0.6 m/s | 4.8 |
| 2020 | 17.9°C | 13.4°C | 9.0°C | 23.7°C | 3.6°C | 17 mm | 77% | 0.5 m/s | 4.7 |
| 2019 | 19.3°C | 13.9°C | 8.5°C | 25.9°C | 5.2°C | 52 mm | 63% | 0.6 m/s | 4.8 |
| 2018 | 19.2°C | 13.6°C | 8.0°C | 28.0°C | 4.0°C | 35 mm | 64% | 0.5 m/s | 4.9 |
| 2017 | 20.5°C | 14.6°C | 8.6°C | 31.8°C | 2.9°C | 2 mm | 51% | 0.6 m/s | 5.4 |
| 2016 | 17.0°C | 12.9°C | 8.8°C | 19.6°C | 5.4°C | 52 mm | 78% | 0.6 m/s | 4.2 |
| 2015 | 16.3°C | 12.2°C | 8.0°C | 21.9°C | 4.1°C | 39 mm | 80% | 0.6 m/s | 4.7 |
| 2014 | 17.0°C | 12.7°C | 8.4°C | 25.0°C | 4.5°C | 38 mm | 78% | 0.5 m/s | 4.8 |
| 2013 | 19.3°C | 14.4°C | 9.5°C | 25.5°C | 5.1°C | 76 mm | 71% | 0.5 m/s | 5.1 |
| 2012 | 19.3°C | 13.8°C | 8.4°C | 26.4°C | 2.5°C | 25 mm | 64% | 0.5 m/s | 5.1 |
| 2011 | 17.5°C | 12.9°C | 8.2°C | 24.5°C | 3.5°C | 57 mm | 73% | 0.6 m/s | 4.6 |
| 2010 | 17.3°C | 12.8°C | 8.3°C | 22.0°C | 4.2°C | 72 mm | 73% | 0.5 m/s | 4.6 |
| 2009 | 20.6°C | 14.9°C | 9.2°C | 28.2°C | 4.2°C | 28 mm | 61% | 0.6 m/s | 5 |
| 2008 | 18.8°C | 13.4°C | 8.0°C | 26.9°C | 2.5°C | 62 mm | 67% | 0.5 m/s | 5 |
| 2007 | 16.7°C | 12.4°C | 8.1°C | 22.0°C | 4.9°C | 38 mm | 74% | 0.6 m/s | 5 |
| 2006 | 18.8°C | 13.9°C | 9.1°C | 26.4°C | 4.8°C | 95 mm | 71% | 0.6 m/s | 5 |
| 2005 | 18.0°C | 13.1°C | 8.2°C | 25.7°C | 4.1°C | 76 mm | 72% | 0.6 m/s | 4.5 |
| 2004 | 18.9°C | 13.7°C | 8.6°C | 26.3°C | 3.8°C | 62 mm | 69% | 0.5 m/s | 4.5 |
| 2003 | 17.8°C | 12.8°C | 7.9°C | 27.6°C | 2.5°C | 15 mm | 64% | 0.6 m/s | 5.2 |
| 2002 | 20.6°C | 14.6°C | 8.7°C | 28.7°C | 3.6°C | 18 mm | 56% | 0.6 m/s | 5 |
| 2001 | 18.8°C | 14.1°C | 9.5°C | 25.4°C | 6.3°C | 37 mm | 77% | 0.5 m/s | 4.4 |
| 2000 | 20.0°C | 14.7°C | 9.4°C | 29.0°C | 4.6°C | 47 mm | 66% | 0.5 m/s | 4.8 |
| 1999 | 17.8°C | 13.5°C | 9.1°C | 23.1°C | 4.5°C | 53 mm | 77% | 0.5 m/s | 4.5 |
| 1998 | 17.5°C | 13.6°C | 9.6°C | 24.3°C | 4.4°C | 50 mm | 83% | 0.5 m/s | 4.5 |
| 1997 | 16.0°C | 12.1°C | 8.3°C | 20.4°C | 4.5°C | 136 mm | 81% | 0.5 m/s | 4.2 |
| 1996 | 16.8°C | 12.4°C | 8.1°C | 23.0°C | 5.4°C | 69 mm | 70% | 0.6 m/s | 4.8 |
| 1995 🌧️ | 16.7°C | 12.2°C | 7.6°C | 25.3°C | 2.5°C | 199 mm | 75% | 0.5 m/s | 4.3 |
| 1994 | 18.4°C | 12.5°C | 6.6°C | 25.3°C | 1.8°C | 14 mm | 57% | 0.6 m/s | 5.4 |
| 1993 | 16.4°C | 12.0°C | 7.6°C | 23.6°C | 4.1°C | 122 mm | 77% | 0.6 m/s | 4.6 |
| 1992 | 16.6°C | 11.4°C | 6.2°C | 23.4°C | 2.8°C | 35 mm | 70% | 0.6 m/s | 4.5 |
| 1991 | 16.2°C | 11.5°C | 6.9°C | 20.0°C | 2.1°C | 24 mm | 73% | 0.6 m/s | 5 |
| 1990 | 15.3°C | 11.4°C | 7.5°C | 22.7°C | 5.3°C | 104 mm | 83% | 0.6 m/s | 4.4 |
| 1989 | 16.2°C | 11.4°C | 6.6°C | 22.1°C | 3.6°C | 12 mm | 77% | 0.6 m/s | 5.1 |
| 1988 | 16.9°C | 12.8°C | 8.7°C | 21.1°C | 5.0°C | 87 mm | 79% | 0.5 m/s | 4.5 |
| 1987 | 17.7°C | 12.6°C | 7.5°C | 25.4°C | 2.5°C | 24 mm | 73% | 0.5 m/s | 5 |
| 1986 | 16.3°C | 12.1°C | 8.0°C | 22.3°C | 4.4°C | 90 mm | 80% | 0.5 m/s | 4.6 |
| 1985 | 15.3°C | 11.2°C | 7.2°C | 20.2°C | 4.2°C | 128 mm | 82% | 0.6 m/s | 4.7 |
| 1984 ❄️ | 14.9°C | 10.8°C | 6.7°C | 18.5°C | 3.3°C | 56 mm | 76% | 0.6 m/s | 4.4 |
| 1983 | 17.9°C | 12.8°C | 7.7°C | 26.5°C | 2.9°C | 44 mm | 73% | 0.5 m/s | — |
| 1982 | 17.1°C | 12.2°C | 7.3°C | 26.9°C | 2.5°C | 153 mm | 68% | 0.6 m/s | — |
| 1981 | 20.9°C | 14.7°C | 8.5°C | 30.3°C | 4.1°C | 9 mm | 64% | 0.5 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 17.9°C with lows near 8.2°C (mean 13.1°C), based on 45 years of NASA POWER data.
September averages 59 mm of rainfall in Kiama, one of the drier months. The wettest on record was 199 mm in 1995.
The hottest September reached 31.8°C in 2017. The coldest dipped to 1.8°C in 1994.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.7°C. Daytime highs moved from 17.2°C to 19°C and overnight lows from 7.5°C to 9°C over the same span.
September is one of the cooler months of the year in Kiama and one of the drier months, so plan for around 17.9°C daytime highs and 8.2°C at night.
Not quite — September is the 4th coolest month in Kiama, averaging 13.1°C.
For September in Kiama, pack light layers you can adjust through the day, with typical highs of 17.9°C and lows of 8.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 71% — moderately humid.
Average wind speed in September is 0.6 m/s. The windiest September on record averaged 0.6 m/s (1982).
The wettest September on record was 1995 with 199 mm. On average, September sees 59 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 Kiama 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.
