September is one of the cooler months of the year in Cessnock, with average highs near 21.4°C and lows around 9.2°C (mean 15.3°C). It is one of the drier months, averaging 49 mm of rainfall and 67% relative humidity across the period.
September is one of the cooler months of the year in Cessnock. Across 45 years of records, the warmest September in Cessnock was 2013 — when the month averaged 18.2°C — while the coldest was 1990 at 12.7°C. Typical September days reach 21.4°C with nights near 9.2°C. The long-term trend is warming, about 0.5°C per decade.
September is one of the drier months in Cessnock, averaging 49 mm of rainfall. The wettest September on record was 1995 with 124 mm, while the driest was 2017 at 1 mm.
Relative humidity in Cessnock during September averages 67%. The most humid September was 1998 at 83%, and the least humid was 2017 at 44%.
September receives about 5 kWh/m²/day of solar energy in Cessnock. The sunniest September was 2017 at 5.7 kWh/m²/day, and the cloudiest were 1995 and 2022 at 4.2.
Average wind speed in Cessnock during September is 0.6 m/s. The windiest Septembers were 1996, 2003 and 2017, among others at 0.7 m/s, while the calmest were 1998 and 1999 at 0.5 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 14.5°C | 14.3°C | 16.0°C | 15.8°C | 16.0°C | +1.5°C |
| Avg High | 20.4°C | 20.2°C | 22.4°C | 22.1°C | 22.1°C | +1.7°C |
| Avg Low | 8.5°C | 8.5°C | 9.7°C | 9.5°C | 9.8°C | +1.3°C |
| Avg Rain | 52 mm | 61 mm | 45 mm | 42 mm | 41 mm | -12 mm |
September temperatures in Cessnock have risen by about 1.1°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 1.9°C (1987) to a record high of 35°C (2017).
Rainfall in September is one of the drier months, averaging 49 mm, with a wettest year of 124 mm.
A good time to visit Cessnock
September is a good time to visit Cessnock, with days averaging 21.4°C and nights around 9.2°C (mean 15.3°C, cooler than Cessnock's yearly average) and moderate rainfall. December 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 | 21.3°C | 15.4°C | 9.5°C | 27.5°C | 5.7°C | 37 mm | 73% | 0.6 m/s | 5.2 |
| 2024 | 23.1°C | 16.6°C | 10.1°C | 29.5°C | 5.6°C | 36 mm | 56% | 0.6 m/s | 5 |
| 2023 | 25.8°C | 18.0°C | 10.3°C | 33.6°C | 5.2°C | 14 mm | 55% | 0.6 m/s | 5.5 |
| 2022 | 18.3°C | 14.1°C | 9.8°C | 21.1°C | 5.5°C | 87 mm | 82% | 0.6 m/s | 4.2 |
| 2021 | 22.1°C | 15.6°C | 9.0°C | 27.8°C | 4.3°C | 35 mm | 62% | 0.6 m/s | 5.1 |
| 2020 | 21.9°C | 16.0°C | 10.2°C | 29.1°C | 5.7°C | 34 mm | 69% | 0.6 m/s | 5 |
| 2019 | 22.3°C | 15.9°C | 9.5°C | 30.1°C | 6.0°C | 52 mm | 63% | 0.6 m/s | 5.3 |
| 2018 | 22.1°C | 15.7°C | 9.3°C | 30.7°C | 5.6°C | 32 mm | 63% | 0.6 m/s | 4.9 |
| 2017 | 24.9°C | 17.4°C | 9.9°C | 35.0°C | 4.5°C | 1 mm | 44% | 0.7 m/s | 5.7 |
| 2016 | 20.5°C | 15.2°C | 9.8°C | 23.1°C | 5.5°C | 71 mm | 70% | 0.6 m/s | 4.6 |
| 2015 | 20.3°C | 14.7°C | 9.1°C | 26.5°C | 3.9°C | 34 mm | 70% | 0.6 m/s | 4.8 |
| 2014 | 20.6°C | 14.9°C | 9.2°C | 29.8°C | 5.4°C | 35 mm | 71% | 0.6 m/s | 5 |
| 2013 🔥 | 25.1°C | 18.2°C | 11.3°C | 31.6°C | 7.1°C | 31 mm | 57% | 0.6 m/s | 5.4 |
| 2012 | 23.4°C | 16.1°C | 8.9°C | 31.2°C | 3.8°C | 23 mm | 58% | 0.6 m/s | 5.6 |
| 2011 | 20.6°C | 14.8°C | 9.0°C | 27.7°C | 4.7°C | 101 mm | 70% | 0.6 m/s | 5 |
| 2010 | 21.5°C | 15.5°C | 9.4°C | 26.5°C | 5.1°C | 37 mm | 68% | 0.6 m/s | 4.7 |
| 2009 | 23.8°C | 17.2°C | 10.5°C | 30.7°C | 5.8°C | 27 mm | 57% | 0.6 m/s | 5.2 |
| 2008 | 20.8°C | 15.1°C | 9.3°C | 29.7°C | 4.2°C | 90 mm | 71% | 0.6 m/s | 5 |
| 2007 | 19.1°C | 14.0°C | 8.8°C | 24.5°C | 6.0°C | 28 mm | 76% | 0.6 m/s | 5.1 |
| 2006 | 22.0°C | 16.1°C | 10.1°C | 31.0°C | 6.2°C | 107 mm | 68% | 0.6 m/s | 4.9 |
| 2005 | 21.5°C | 15.3°C | 9.2°C | 29.7°C | 6.2°C | 54 mm | 66% | 0.6 m/s | 4.8 |
| 2004 | 22.2°C | 15.8°C | 9.4°C | 32.5°C | 3.5°C | 52 mm | 64% | 0.6 m/s | 4.9 |
| 2003 | 23.1°C | 16.1°C | 9.2°C | 34.4°C | 5.1°C | 5 mm | 54% | 0.7 m/s | 5.4 |
| 2002 | 23.9°C | 16.8°C | 9.7°C | 32.0°C | 5.6°C | 29 mm | 55% | 0.6 m/s | 5 |
| 2001 | 22.7°C | 16.5°C | 10.2°C | 28.6°C | 7.2°C | 25 mm | 68% | 0.6 m/s | 4.6 |
| 2000 | 24.4°C | 17.3°C | 10.3°C | 33.6°C | 5.6°C | 36 mm | 61% | 0.6 m/s | 5.2 |
| 1999 | 20.6°C | 15.0°C | 9.4°C | 26.5°C | 4.6°C | 65 mm | 75% | 0.5 m/s | 4.6 |
| 1998 | 19.8°C | 15.1°C | 10.4°C | 27.4°C | 4.0°C | 60 mm | 83% | 0.5 m/s | 4.4 |
| 1997 | 19.8°C | 14.5°C | 9.1°C | 25.0°C | 5.4°C | 76 mm | 74% | 0.6 m/s | 4.3 |
| 1996 | 20.3°C | 14.4°C | 8.5°C | 27.3°C | 4.4°C | 84 mm | 68% | 0.7 m/s | 4.8 |
| 1995 🌧️ | 20.0°C | 14.4°C | 8.9°C | 27.1°C | 2.8°C | 124 mm | 70% | 0.6 m/s | 4.2 |
| 1994 | 22.3°C | 15.0°C | 7.6°C | 27.4°C | 3.5°C | 8 mm | 51% | 0.7 m/s | 5.5 |
| 1993 | 19.3°C | 13.7°C | 8.0°C | 25.4°C | 3.4°C | 71 mm | 74% | 0.6 m/s | 4.8 |
| 1992 | 20.0°C | 13.6°C | 7.2°C | 27.0°C | 2.4°C | 33 mm | 62% | 0.6 m/s | 4.8 |
| 1991 | 21.9°C | 15.0°C | 8.1°C | 27.2°C | 3.0°C | 20 mm | 57% | 0.7 m/s | 5.5 |
| 1990 ❄️ | 17.5°C | 12.7°C | 8.0°C | 23.5°C | 4.7°C | 70 mm | 82% | 0.6 m/s | 4.5 |
| 1989 | 18.8°C | 13.0°C | 7.2°C | 25.8°C | 2.7°C | 11 mm | 74% | 0.6 m/s | 5.2 |
| 1988 | 19.8°C | 14.8°C | 9.8°C | 24.5°C | 6.2°C | 105 mm | 78% | 0.6 m/s | 4.6 |
| 1987 | 20.7°C | 14.3°C | 7.8°C | 28.3°C | 1.9°C | 15 mm | 71% | 0.6 m/s | 5.4 |
| 1986 | 19.5°C | 14.1°C | 8.7°C | 26.7°C | 3.2°C | 70 mm | 76% | 0.6 m/s | 4.8 |
| 1985 | 19.0°C | 13.5°C | 8.0°C | 23.9°C | 4.8°C | 63 mm | 74% | 0.6 m/s | 5 |
| 1984 | 19.4°C | 13.3°C | 7.2°C | 24.9°C | 4.1°C | 33 mm | 65% | 0.6 m/s | 4.9 |
| 1983 | 21.8°C | 15.5°C | 9.2°C | 29.8°C | 4.8°C | 46 mm | 68% | 0.6 m/s | — |
| 1982 | 20.6°C | 14.6°C | 8.5°C | 29.8°C | 3.9°C | 116 mm | 63% | 0.6 m/s | — |
| 1981 | 24.4°C | 17.1°C | 9.7°C | 31.4°C | 3.9°C | 12 mm | 59% | 0.6 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 21.4°C with lows near 9.2°C (mean 15.3°C), based on 45 years of NASA POWER data.
September averages 49 mm of rainfall in Cessnock, one of the drier months. The wettest on record was 124 mm in 1995.
The hottest September reached 35°C in 2017. The coldest dipped to 1.9°C in 1987.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.1°C. Daytime highs moved from 21°C to 22.1°C and overnight lows from 8.5°C to 9.7°C over the same span.
September is one of the cooler months of the year in Cessnock and one of the drier months, so plan for around 21.4°C daytime highs and 9.2°C at night.
Not quite — September is the 5th coolest month in Cessnock, averaging 15.3°C.
For September in Cessnock, pack light layers you can adjust through the day, with typical highs of 21.4°C and lows of 9.2°C.
Relative humidity in September averages 67% — moderately humid.
Average wind speed in September is 0.6 m/s. The windiest September on record averaged 0.7 m/s (1991).
The wettest September on record was 1995 with 124 mm. On average, September sees 49 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 Cessnock 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.
