September is one of the cooler months of the year in Kalgoorlie, with average highs near 23.8°C and lows around 7.8°C (mean 15.8°C). It is one of the drier months, averaging 12 mm of rainfall and 52% relative humidity across the period.
September is one of the cooler months of the year in Kalgoorlie. Across 45 years of records, the warmest September in Kalgoorlie was 2023 — when the month averaged 19.9°C — while the coldest was 1992 at 12.3°C. Typical September days reach 23.8°C with nights near 7.8°C. The long-term trend is warming, about 0.2°C per decade.
September is one of the drier months in Kalgoorlie, averaging 12 mm of rainfall. The wettest September on record was 1984 with 50 mm, while the driest was 2020 at 0 mm.
Relative humidity in Kalgoorlie during September averages 52%. The most humid September was 1992 at 72%, and the least humid was 2002 at 44%.
September receives about 5.7 kWh/m²/day of solar energy in Kalgoorlie. The sunniest Septembers were 1989 and 2002 at 6.2 kWh/m²/day, and the cloudiest was 1992 at 4.9.
Average wind speed in Kalgoorlie during September is 3.4 m/s. The windiest September was 1996 at 3.9 m/s, while the calmest was 1986 at 2.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 15.9°C | 15.3°C | 15.8°C | 15.8°C | 16.7°C | +0.8°C |
| Avg High | 23.9°C | 23.0°C | 23.9°C | 23.8°C | 24.8°C | +0.9°C |
| Avg Low | 7.8°C | 7.5°C | 7.6°C | 7.8°C | 8.5°C | +0.7°C |
| Avg Rain | 13 mm | 13 mm | 13 mm | 13 mm | 8 mm | -5 mm |
September temperatures in Kalgoorlie have risen by about 0.6°C between 1981–1985 and 2021–2025.
September has ranged from a record low of -0.1°C (2004) to a record high of 37.3°C (2023).
Rainfall in September is one of the drier months, averaging 12 mm, with a wettest year of 50 mm.
A good time to visit Kalgoorlie
September is a good time to visit Kalgoorlie, with days averaging 23.8°C and nights around 7.8°C (mean 15.8°C, cooler than Kalgoorlie's yearly average) and low rainfall. November and March 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 | 23.8°C | 15.7°C | 7.6°C | 32.4°C | 4.3°C | 5 mm | 50% | 3.3 m/s | 6 |
| 2024 | 24.6°C | 16.4°C | 8.3°C | 32.6°C | 2.6°C | 13 mm | 49% | 3.3 m/s | 5.9 |
| 2023 🔥 | 28.4°C | 19.9°C | 11.4°C | 37.3°C | 3.3°C | 2 mm | 45% | 3.6 m/s | 5.8 |
| 2022 | 22.4°C | 15.2°C | 8.0°C | 28.0°C | 5.0°C | 22 mm | 56% | 3.5 m/s | 5.5 |
| 2021 | 23.7°C | 15.3°C | 6.8°C | 30.5°C | 0.4°C | 3 mm | 47% | 3.5 m/s | 5.8 |
| 2020 | 25.8°C | 17.4°C | 9.1°C | 33.3°C | 5.7°C | 0 mm | 46% | 3.7 m/s | 5.6 |
| 2019 | 26.9°C | 18.1°C | 9.2°C | 35.8°C | 0.9°C | 0 mm | 46% | 3.2 m/s | 6 |
| 2018 | 24.4°C | 16.0°C | 7.6°C | 34.0°C | 1.1°C | 24 mm | 48% | 3.2 m/s | 5.9 |
| 2017 | 23.7°C | 16.2°C | 8.7°C | 34.6°C | 2.2°C | 12 mm | 50% | 3.4 m/s | 5.4 |
| 2016 | 21.1°C | 13.2°C | 5.2°C | 31.6°C | 0.6°C | 3 mm | 52% | 3.4 m/s | 5.8 |
| 2015 | 24.5°C | 15.8°C | 7.1°C | 32.0°C | 0.9°C | 1 mm | 49% | 3.1 m/s | 6.1 |
| 2014 | 25.4°C | 17.5°C | 9.7°C | 33.9°C | 4.8°C | 16 mm | 52% | 3.6 m/s | 5.5 |
| 2013 | 23.3°C | 16.1°C | 8.9°C | 30.5°C | 4.5°C | 28 mm | 55% | 3.6 m/s | 5.3 |
| 2012 | 23.9°C | 16.0°C | 8.1°C | 30.7°C | 2.8°C | 14 mm | 51% | 3.6 m/s | 5.9 |
| 2011 | 23.1°C | 15.1°C | 7.0°C | 29.5°C | 3.7°C | 18 mm | 55% | 3.2 m/s | 5.9 |
| 2010 | 21.6°C | 13.9°C | 6.2°C | 32.3°C | 2.7°C | 15 mm | 56% | 3.2 m/s | 5.5 |
| 2009 | 21.8°C | 13.9°C | 6.0°C | 28.3°C | 1.8°C | 17 mm | 52% | 3.8 m/s | 5.8 |
| 2008 | 24.2°C | 15.9°C | 7.7°C | 32.4°C | 3.1°C | 17 mm | 52% | 3.6 m/s | 5.9 |
| 2007 | 25.2°C | 16.7°C | 8.1°C | 31.9°C | 4.1°C | 8 mm | 46% | 3.6 m/s | 6 |
| 2006 | 24.6°C | 16.8°C | 9.0°C | 33.5°C | 4.5°C | 19 mm | 49% | 3.6 m/s | 5.6 |
| 2005 | 22.7°C | 14.8°C | 7.0°C | 30.3°C | 0.9°C | 14 mm | 53% | 3.6 m/s | 5.8 |
| 2004 | 23.8°C | 15.6°C | 7.3°C | 32.4°C | -0.1°C | 11 mm | 49% | 3 m/s | 5.3 |
| 2003 | 23.1°C | 15.3°C | 7.5°C | 30.8°C | 4.0°C | 24 mm | 56% | 3.8 m/s | 5.4 |
| 2002 | 24.5°C | 15.9°C | 7.3°C | 32.9°C | 2.4°C | 5 mm | 44% | 3.5 m/s | 6.2 |
| 2001 | 24.1°C | 15.7°C | 7.4°C | 33.3°C | 1.3°C | 16 mm | 52% | 3.6 m/s | 5.6 |
| 2000 | 25.5°C | 17.0°C | 8.5°C | 33.9°C | 3.1°C | 2 mm | 51% | 3 m/s | 6 |
| 1999 | 23.9°C | 16.0°C | 8.1°C | 33.2°C | 1.9°C | 17 mm | 53% | 3.7 m/s | 5.5 |
| 1998 | 22.3°C | 14.7°C | 7.0°C | 28.2°C | 1.8°C | 16 mm | 58% | 3.6 m/s | 5.3 |
| 1997 | 23.8°C | 16.0°C | 8.2°C | 30.4°C | 2.7°C | 8 mm | 56% | 3 m/s | 5.7 |
| 1996 | 22.9°C | 15.3°C | 7.6°C | 31.0°C | 3.2°C | 18 mm | 55% | 3.9 m/s | 5.7 |
| 1995 | 24.2°C | 16.4°C | 8.5°C | 31.5°C | 3.8°C | 13 mm | 55% | 3 m/s | 5.4 |
| 1994 | 24.7°C | 16.3°C | 8.0°C | 30.4°C | 2.8°C | 6 mm | 49% | 3.5 m/s | 5.9 |
| 1993 | 22.0°C | 14.5°C | 7.0°C | 27.4°C | 1.4°C | 7 mm | 55% | 3.3 m/s | 5.5 |
| 1992 ❄️ | 18.5°C | 12.3°C | 6.1°C | 25.2°C | 2.1°C | 34 mm | 72% | 3.3 m/s | 4.9 |
| 1991 | 24.1°C | 15.8°C | 7.6°C | 33.7°C | 2.1°C | 6 mm | 51% | 3.3 m/s | 6 |
| 1990 | 24.0°C | 15.6°C | 7.3°C | 32.4°C | 1.9°C | 6 mm | 50% | 3.1 m/s | 6.1 |
| 1989 | 24.2°C | 15.8°C | 7.4°C | 32.1°C | 3.0°C | 1 mm | 50% | 3.3 m/s | 6.2 |
| 1988 | 24.3°C | 16.0°C | 7.8°C | 29.6°C | 3.3°C | 2 mm | 50% | 3.3 m/s | 5.9 |
| 1987 | 24.6°C | 16.3°C | 8.1°C | 35.2°C | 2.4°C | 2 mm | 45% | 3 m/s | 5.8 |
| 1986 | 22.9°C | 15.3°C | 7.7°C | 28.3°C | 2.3°C | 19 mm | 56% | 2.9 m/s | 5.4 |
| 1985 | 24.0°C | 16.2°C | 8.3°C | 30.8°C | 1.8°C | 10 mm | 48% | 3.3 m/s | 5.8 |
| 1984 🌧️ | 20.2°C | 13.0°C | 5.7°C | 26.1°C | 2.4°C | 50 mm | 57% | 3.2 m/s | 5.6 |
| 1983 | 25.5°C | 17.4°C | 9.3°C | 34.1°C | 5.3°C | 17 mm | 50% | 3.5 m/s | — |
| 1982 | 23.4°C | 15.3°C | 7.2°C | 29.7°C | 2.4°C | 14 mm | 49% | 3.1 m/s | — |
| 1981 | 26.1°C | 17.4°C | 8.7°C | 32.7°C | 2.5°C | 1 mm | 46% | 3.1 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 23.8°C with lows near 7.8°C (mean 15.8°C), based on 45 years of NASA POWER data.
September averages 12 mm of rainfall in Kalgoorlie, one of the drier months. The wettest on record was 50 mm in 1984.
The hottest September reached 37.3°C in 2023. The coldest dipped to -0.1°C in 2004.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 0.6°C. Daytime highs moved from 23.8°C to 24.6°C and overnight lows from 7.8°C to 8.4°C over the same span.
September is one of the cooler months of the year in Kalgoorlie and one of the drier months, so plan for around 23.8°C daytime highs and 7.8°C at night.
Not quite — September is the 5th coolest month in Kalgoorlie, averaging 15.8°C.
For September in Kalgoorlie, pack warm layers and a jacket for chilly mornings, with typical highs of 23.8°C and lows of 7.8°C.
Relative humidity in September averages 52% — relatively dry.
Average wind speed in September is 3.4 m/s. The windiest September on record averaged 3.9 m/s (1996).
The wettest September on record was 1984 with 50 mm. On average, September sees 12 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 Kalgoorlie 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.
