September is one of the cooler months of the year in Cranbourne, with average highs near 15.4°C and lows around 7.8°C (mean 11.6°C). It is about average for rainfall, averaging 69 mm of rainfall and 79% relative humidity across the period.
September is one of the cooler months of the year in Cranbourne. Across 45 years of records, the warmest September in Cranbourne was 2023 — when the month averaged 13.9°C — while the coldest was 1992 at 9.6°C. Typical September days reach 15.4°C with nights near 7.8°C. The long-term trend is warming, about 0.4°C per decade.
September is about average for rainfall in Cranbourne, averaging 69 mm of rainfall. The wettest September on record was 1993 with 143 mm, while the driest was 2015 at 26 mm.
Relative humidity in Cranbourne during September averages 79%. The most humid September was 1992 at 85%, and the least humid was 2002 at 71%.
September receives about 4 kWh/m²/day of solar energy in Cranbourne. The sunniest Septembers were 1985, 2018 and 2023 at 4.4 kWh/m²/day, and the cloudiest was 1992 at 3.5.
Average wind speed in Cranbourne during September is 3.5 m/s. The windiest September was 1996 at 4.5 m/s, while the calmest was 1997 at 2.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 11.1°C | 11.0°C | 12.0°C | 11.9°C | 12.4°C | +1.3°C |
| Avg High | 14.9°C | 14.6°C | 15.9°C | 15.7°C | 16.3°C | +1.4°C |
| Avg Low | 7.3°C | 7.3°C | 8.0°C | 8.0°C | 8.5°C | +1.2°C |
| Avg Rain | 69 mm | 85 mm | 65 mm | 62 mm | 58 mm | -11 mm |
September temperatures in Cranbourne have risen by about 1.6°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 3°C (2013) to a record high of 26°C (2023).
Rainfall in September is about average for rainfall, averaging 69 mm, with a wettest year of 143 mm.
A quieter season to visit Cranbourne
If your dates are flexible, the more temperate months of February and January tend to be the most comfortable for visiting Cranbourne. That said, September — with days averaging 15.4°C and nights around 7.8°C (mean 11.6°C) and moderate rainfall (69 mm) — can still be rewarding for travellers who don't mind the cooler conditions, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 16.6°C | 12.7°C | 8.7°C | 21.5°C | 3.8°C | 33 mm | 74% | 4 m/s | 3.8 |
| 2024 | 16.4°C | 12.6°C | 8.7°C | 21.8°C | 5.8°C | 61 mm | 74% | 4 m/s | 3.7 |
| 2023 🔥 | 18.7°C | 13.9°C | 9.1°C | 26.0°C | 5.6°C | 30 mm | 71% | 3.1 m/s | 4.4 |
| 2022 | 14.9°C | 11.5°C | 8.1°C | 17.7°C | 3.3°C | 58 mm | 84% | 3.1 m/s | 3.8 |
| 2021 | 15.8°C | 11.9°C | 8.1°C | 20.7°C | 5.3°C | 109 mm | 78% | 3.7 m/s | 4.1 |
| 2020 | 15.6°C | 11.8°C | 8.0°C | 21.0°C | 5.1°C | 59 mm | 79% | 3.6 m/s | 4.1 |
| 2019 | 15.9°C | 11.9°C | 7.9°C | 21.4°C | 5.1°C | 64 mm | 77% | 3.2 m/s | 4.1 |
| 2018 | 16.0°C | 11.5°C | 6.9°C | 21.8°C | 3.6°C | 26 mm | 73% | 3.2 m/s | 4.4 |
| 2017 | 15.7°C | 11.7°C | 7.7°C | 25.4°C | 3.2°C | 59 mm | 74% | 4.3 m/s | 3.9 |
| 2016 | 14.9°C | 11.5°C | 8.1°C | 19.5°C | 6.2°C | 80 mm | 83% | 3.1 m/s | 3.9 |
| 2015 | 15.6°C | 11.7°C | 7.7°C | 21.9°C | 5.1°C | 26 mm | 78% | 3.1 m/s | 4.2 |
| 2014 | 16.3°C | 12.5°C | 8.6°C | 23.5°C | 6.2°C | 55 mm | 78% | 3.2 m/s | 4.3 |
| 2013 | 16.6°C | 13.0°C | 9.3°C | 22.0°C | 3.0°C | 93 mm | 81% | 3.5 m/s | 3.9 |
| 2012 | 15.4°C | 11.8°C | 8.2°C | 21.7°C | 4.4°C | 60 mm | 80% | 3.5 m/s | 3.9 |
| 2011 | 16.2°C | 12.2°C | 8.2°C | 22.4°C | 5.8°C | 78 mm | 76% | 3.7 m/s | 4.2 |
| 2010 | 13.9°C | 10.7°C | 7.5°C | 17.9°C | 4.0°C | 74 mm | 83% | 3.4 m/s | 3.7 |
| 2009 | 15.9°C | 12.0°C | 8.1°C | 22.9°C | 5.1°C | 104 mm | 77% | 3.9 m/s | 3.8 |
| 2008 | 16.4°C | 12.1°C | 7.8°C | 24.2°C | 4.7°C | 34 mm | 72% | 3.6 m/s | 4.3 |
| 2007 | 15.9°C | 11.8°C | 7.6°C | 18.6°C | 4.0°C | 44 mm | 75% | 3.8 m/s | 4.1 |
| 2006 | 17.3°C | 12.8°C | 8.3°C | 24.7°C | 4.8°C | 43 mm | 71% | 3.5 m/s | 4.2 |
| 2005 | 15.7°C | 12.1°C | 8.4°C | 20.8°C | 4.3°C | 76 mm | 79% | 3.3 m/s | 4 |
| 2004 | 15.0°C | 11.5°C | 7.9°C | 20.5°C | 4.9°C | 88 mm | 84% | 2.9 m/s | 3.7 |
| 2003 | 14.5°C | 10.7°C | 6.9°C | 20.1°C | 3.3°C | 56 mm | 79% | 4.3 m/s | 4 |
| 2002 | 16.3°C | 12.0°C | 7.8°C | 23.1°C | 5.7°C | 58 mm | 71% | 4.3 m/s | 4 |
| 2001 | 16.6°C | 12.6°C | 8.6°C | 23.0°C | 4.8°C | 47 mm | 80% | 3.1 m/s | 3.8 |
| 2000 | 15.6°C | 11.9°C | 8.2°C | 19.3°C | 5.2°C | 104 mm | 82% | 3.9 m/s | 4 |
| 1999 | 16.6°C | 12.7°C | 8.7°C | 22.6°C | 5.5°C | 48 mm | 78% | 3.2 m/s | 4 |
| 1998 | 16.4°C | 12.4°C | 8.4°C | 23.1°C | 5.7°C | 57 mm | 79% | 3.5 m/s | 4 |
| 1997 | 15.2°C | 11.5°C | 7.7°C | 18.2°C | 5.5°C | 67 mm | 81% | 2.5 m/s | 4.2 |
| 1996 | 14.0°C | 10.4°C | 6.8°C | 19.3°C | 3.5°C | 122 mm | 82% | 4.5 m/s | 3.8 |
| 1995 | 14.1°C | 10.3°C | 6.4°C | 18.8°C | 3.6°C | 49 mm | 83% | 3 m/s | 4.1 |
| 1994 | 13.8°C | 10.1°C | 6.4°C | 20.0°C | 4.1°C | 69 mm | 77% | 3.6 m/s | 3.8 |
| 1993 🌧️ | 14.6°C | 11.2°C | 7.8°C | 21.4°C | 3.7°C | 143 mm | 85% | 3.3 m/s | 4 |
| 1992 ❄️ | 12.6°C | 9.6°C | 6.5°C | 15.1°C | 3.1°C | 134 mm | 85% | 3.2 m/s | 3.5 |
| 1991 | 14.1°C | 10.5°C | 6.9°C | 18.5°C | 3.5°C | 103 mm | 83% | 3.4 m/s | 3.8 |
| 1990 | 15.0°C | 11.3°C | 7.5°C | 20.3°C | 5.2°C | 62 mm | 82% | 3.3 m/s | 4.1 |
| 1989 | 14.7°C | 11.0°C | 7.3°C | 20.3°C | 5.4°C | 59 mm | 83% | 3.4 m/s | 4.3 |
| 1988 | 15.9°C | 11.9°C | 7.9°C | 20.1°C | 5.1°C | 70 mm | 80% | 3.7 m/s | 4 |
| 1987 | 15.9°C | 11.9°C | 8.0°C | 23.6°C | 4.6°C | 49 mm | 81% | 3.4 m/s | 4.1 |
| 1986 | 14.4°C | 10.9°C | 7.3°C | 19.9°C | 5.0°C | 66 mm | 84% | 3.3 m/s | 3.9 |
| 1985 | 14.2°C | 10.8°C | 7.4°C | 19.4°C | 5.0°C | 47 mm | 82% | 3.1 m/s | 4.4 |
| 1984 | 13.6°C | 10.3°C | 7.0°C | 17.9°C | 4.5°C | 125 mm | 82% | 3.4 m/s | 4 |
| 1983 | 14.4°C | 10.7°C | 7.1°C | 19.3°C | 3.7°C | 110 mm | 84% | 3.8 m/s | — |
| 1982 | 15.5°C | 10.9°C | 6.4°C | 21.5°C | 4.3°C | 61 mm | 74% | 3.3 m/s | — |
| 1981 | 15.9°C | 11.8°C | 7.7°C | 22.4°C | 5.5°C | 36 mm | 83% | 3.4 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 15.4°C with lows near 7.8°C (mean 11.6°C), based on 45 years of NASA POWER data.
September averages 69 mm of rainfall in Cranbourne, about average for rainfall. The wettest on record was 143 mm in 1993.
The hottest September reached 26°C in 2023. The coldest dipped to 3°C in 2013.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.6°C. Daytime highs moved from 14.7°C to 16.5°C and overnight lows from 7.1°C to 8.5°C over the same span.
September is one of the cooler months of the year in Cranbourne and about average for rainfall, so plan for around 15.4°C daytime highs and 7.8°C at night.
Not quite — September is the 4th coolest month in Cranbourne, averaging 11.6°C.
For September in Cranbourne, pack warm layers and a jacket for chilly mornings, with typical highs of 15.4°C and lows of 7.8°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 79% — quite humid.
Average wind speed in September is 3.5 m/s. The windiest September on record averaged 4.5 m/s (1996).
The wettest September on record was 1993 with 143 mm. On average, September sees 69 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 Cranbourne 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.
