September is one of the cooler months of the year in Karratha, with average highs near 26.7°C and lows around 21.1°C (mean 23.9°C). It is one of the drier months, averaging 2 mm of rainfall and 60% relative humidity across the period.
September is one of the cooler months of the year in Karratha. Across 45 years of records, the warmest September in Karratha was 2020 — when the month averaged 26.2°C — while the coldest was 2004 at 22.5°C. Typical September days reach 26.7°C with nights near 21.1°C. The long-term trend is warming, about 0.2°C per decade.
September is one of the drier months in Karratha, averaging 2 mm of rainfall. The wettest September on record was 2010 with 22 mm, while the driest were 2020, 2021 and 2023, among others at 0 mm.
Relative humidity in Karratha during September averages 60%. The most humid September was 1995 at 65%, and the least humid was 2021 at 56%.
September receives about 6.6 kWh/m²/day of solar energy in Karratha. The sunniest September was 2002 at 6.9 kWh/m²/day, and the cloudiest was 2001 at 5.9.
Average wind speed in Karratha during September is 4.6 m/s. The windiest September was 1991 at 5.2 m/s, while the calmest were 2000 and 2006 at 3.9 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 24.0°C | 23.6°C | 23.6°C | 23.8°C | 25.0°C | +1°C |
| Avg High | 26.8°C | 26.5°C | 26.3°C | 26.7°C | 27.8°C | +1°C |
| Avg Low | 21.2°C | 20.7°C | 20.9°C | 21.0°C | 22.2°C | +1°C |
| Avg Rain | 2 mm | 0 mm | 0 mm | 3 mm | 3 mm | +1 mm |
September temperatures in Karratha have risen by about 0.5°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 15.9°C (1992) to a record high of 35.9°C (2006).
Rainfall in September is one of the drier months, averaging 2 mm, with a wettest year of 22 mm.
One of the best times to visit Karratha
September is one of the best times to visit Karratha. Expect days averaging 26.7°C and nights around 21.1°C (mean 23.9°C) — cooler than Karratha's yearly average — with low rainfall (2 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 | 27.3°C | 24.2°C | 21.1°C | 31.5°C | 18.5°C | 2 mm | 57% | 4.5 m/s | 6.7 |
| 2024 | 28.2°C | 26.1°C | 24.0°C | 31.5°C | 21.4°C | 5 mm | 62% | 4 m/s | 6.1 |
| 2023 | 28.5°C | 25.6°C | 22.7°C | 34.1°C | 19.1°C | 0 mm | 62% | 4 m/s | 6.5 |
| 2022 | 25.9°C | 23.4°C | 20.9°C | 29.6°C | 18.4°C | 7 mm | 62% | 4.6 m/s | 6.5 |
| 2021 | 27.2°C | 24.3°C | 21.3°C | 31.2°C | 19.4°C | 0 mm | 56% | 4.9 m/s | 6.6 |
| 2020 🔥 | 29.4°C | 26.2°C | 23.0°C | 33.4°C | 21.0°C | 0 mm | 56% | 4.6 m/s | 6.8 |
| 2019 | 26.8°C | 23.9°C | 21.0°C | 29.5°C | 19.7°C | 1 mm | 61% | 4.2 m/s | 6.8 |
| 2018 | 27.0°C | 24.0°C | 21.0°C | 33.7°C | 18.0°C | 0 mm | 59% | 4.3 m/s | 6.7 |
| 2017 | 27.2°C | 24.5°C | 21.8°C | 32.4°C | 19.4°C | 1 mm | 60% | 4.8 m/s | 6.7 |
| 2016 | 26.0°C | 23.4°C | 20.8°C | 27.3°C | 18.9°C | 4 mm | 59% | 4.6 m/s | 6.6 |
| 2015 | 27.4°C | 24.5°C | 21.7°C | 29.2°C | 18.8°C | 0 mm | 59% | 4 m/s | 6.8 |
| 2014 | 27.5°C | 24.5°C | 21.5°C | 31.9°C | 19.6°C | 0 mm | 60% | 4.5 m/s | 6.7 |
| 2013 | 26.2°C | 23.5°C | 20.9°C | 31.5°C | 18.5°C | 3 mm | 64% | 4.9 m/s | 6.7 |
| 2012 | 26.7°C | 24.0°C | 21.2°C | 29.9°C | 18.9°C | 0 mm | 63% | 5 m/s | 6.7 |
| 2011 | 26.2°C | 23.2°C | 20.2°C | 29.8°C | 18.7°C | 0 mm | 58% | 5.1 m/s | 6.8 |
| 2010 🌧️ | 25.7°C | 22.9°C | 20.2°C | 32.4°C | 17.8°C | 22 mm | 60% | 4.9 m/s | 6 |
| 2009 | 25.9°C | 23.0°C | 20.2°C | 28.6°C | 17.7°C | 0 mm | 59% | 5 m/s | 6.8 |
| 2008 | 27.2°C | 24.4°C | 21.5°C | 32.5°C | 19.6°C | 1 mm | 59% | 4.4 m/s | 6.5 |
| 2007 | 27.2°C | 24.2°C | 21.3°C | 29.6°C | 18.9°C | 0 mm | 58% | 4.6 m/s | 6.8 |
| 2006 | 27.5°C | 24.8°C | 22.0°C | 35.9°C | 20.0°C | 2 mm | 64% | 3.9 m/s | 6.6 |
| 2005 | 25.3°C | 22.8°C | 20.2°C | 28.7°C | 18.2°C | 0 mm | 64% | 4.9 m/s | 6.7 |
| 2004 ❄️ | 25.1°C | 22.5°C | 19.9°C | 27.4°C | 17.0°C | 0 mm | 61% | 4.9 m/s | 6.7 |
| 2003 | 25.7°C | 23.0°C | 20.4°C | 28.3°C | 18.4°C | 0 mm | 62% | 4.9 m/s | 6.7 |
| 2002 | 25.4°C | 22.9°C | 20.3°C | 28.2°C | 17.8°C | 0 mm | 65% | 4.7 m/s | 6.9 |
| 2001 | 26.3°C | 23.9°C | 21.4°C | 31.1°C | 18.8°C | 0 mm | 60% | 4.4 m/s | 5.9 |
| 2000 | 27.4°C | 24.5°C | 21.7°C | 32.1°C | 18.6°C | 0 mm | 62% | 3.9 m/s | 6.7 |
| 1999 | 27.4°C | 24.4°C | 21.4°C | 29.7°C | 19.6°C | 0 mm | 59% | 4.7 m/s | 6.7 |
| 1998 | 27.4°C | 24.2°C | 21.0°C | 33.2°C | 18.3°C | 0 mm | 58% | 5.1 m/s | 6.5 |
| 1997 | 25.6°C | 22.9°C | 20.1°C | 27.8°C | 17.1°C | 3 mm | 65% | 4.7 m/s | 6.5 |
| 1996 | 26.6°C | 23.7°C | 20.9°C | 32.3°C | 19.6°C | 0 mm | 62% | 4.9 m/s | 6.7 |
| 1995 | 26.0°C | 23.6°C | 21.3°C | 29.7°C | 18.9°C | 1 mm | 65% | 4.8 m/s | 6.4 |
| 1994 | 27.9°C | 24.5°C | 21.0°C | 31.6°C | 18.4°C | 0 mm | 59% | 4.6 m/s | 6.7 |
| 1993 | 26.0°C | 23.0°C | 20.0°C | 30.8°C | 16.5°C | 0 mm | 57% | 4.7 m/s | 6.7 |
| 1992 | 25.3°C | 22.6°C | 19.9°C | 29.8°C | 15.9°C | 0 mm | 60% | 4.9 m/s | 6.3 |
| 1991 | 25.9°C | 23.0°C | 20.1°C | 30.5°C | 18.5°C | 0 mm | 59% | 5.2 m/s | 6.6 |
| 1990 | 26.7°C | 23.8°C | 21.0°C | 33.6°C | 19.6°C | 0 mm | 60% | 4.6 m/s | 6.5 |
| 1989 | 27.9°C | 24.6°C | 21.4°C | 30.1°C | 20.0°C | 0 mm | 56% | 4.3 m/s | 6.4 |
| 1988 | 27.0°C | 23.9°C | 20.8°C | 29.1°C | 18.9°C | 0 mm | 57% | 4.6 m/s | 6.7 |
| 1987 | 26.6°C | 23.8°C | 21.0°C | 30.7°C | 19.2°C | 0 mm | 61% | 4.3 m/s | 6.5 |
| 1986 | 25.1°C | 22.6°C | 20.1°C | 28.3°C | 18.1°C | 6 mm | 64% | 4.7 m/s | 6.3 |
| 1985 | 27.0°C | 24.1°C | 21.3°C | 31.3°C | 18.7°C | 0 mm | 59% | 4.3 m/s | 6.5 |
| 1984 | 25.6°C | 23.0°C | 20.4°C | 28.3°C | 18.3°C | 4 mm | 62% | 4.8 m/s | 6.5 |
| 1983 | 27.8°C | 24.9°C | 22.0°C | 32.0°C | 18.7°C | 4 mm | 61% | 4.4 m/s | — |
| 1982 | 26.2°C | 23.8°C | 21.4°C | 32.7°C | 18.9°C | 3 mm | 61% | 4.7 m/s | — |
| 1981 | 28.4°C | 25.3°C | 22.2°C | 32.2°C | 19.5°C | 0 mm | 57% | 4.7 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 26.7°C with lows near 21.1°C (mean 23.9°C), based on 45 years of NASA POWER data.
September averages 2 mm of rainfall in Karratha, one of the drier months. The wettest on record was 22 mm in 2010.
The hottest September reached 35.9°C in 2006. The coldest dipped to 15.9°C in 1992.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 0.5°C. Daytime highs moved from 27°C to 27.4°C and overnight lows from 21.5°C to 22°C over the same span.
September is one of the cooler months of the year in Karratha and one of the drier months, so plan for around 26.7°C daytime highs and 21.1°C at night.
Not quite — September is the 4th coolest month in Karratha, averaging 23.9°C.
For September in Karratha, pack light layers you can adjust through the day, with typical highs of 26.7°C and lows of 21.1°C.
Relative humidity in September averages 60% — moderately humid.
Average wind speed in September is 4.6 m/s. The windiest September on record averaged 5.2 m/s (1991).
The wettest September on record was 2010 with 22 mm. On average, September sees 2 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 Karratha 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.
