September is one of the cooler months of the year in Newcastle, with average highs near 19.9°C and lows around 13.9°C (mean 16.9°C). It is one of the drier months, averaging 56 mm of rainfall and 69% relative humidity across the period.
September is one of the cooler months of the year in Newcastle. Across 45 years of records, the warmest September in Newcastle was 2013 — when the month averaged 19.4°C — while the coldest was 1990 at 14.8°C. Typical September days reach 19.9°C with nights near 13.9°C. The long-term trend is warming, about 0.4°C per decade.
September is one of the drier months in Newcastle, averaging 56 mm of rainfall. The wettest September on record was 1982 with 176 mm, while the driest was 2017 at 2 mm.
Relative humidity in Newcastle during September averages 69%. The most humid September was 1998 at 79%, and the least humid was 2017 at 54%.
September receives about 5 kWh/m²/day of solar energy in Newcastle. 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 Newcastle during September is 3 m/s. The windiest September was 1996 at 3.4 m/s, while the calmest was 2023 at 2.4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 16.2°C | 16.2°C | 17.4°C | 17.3°C | 17.6°C | +1.4°C |
| Avg High | 19.3°C | 19.0°C | 20.4°C | 20.3°C | 20.6°C | +1.3°C |
| Avg Low | 13.2°C | 13.4°C | 14.3°C | 14.3°C | 14.5°C | +1.3°C |
| Avg Rain | 63 mm | 65 mm | 59 mm | 45 mm | 39 mm | -24 mm |
September temperatures in Newcastle have risen by about 1.4°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 7.6°C (1987) to a record high of 29.3°C (2000).
Rainfall in September is one of the drier months, averaging 56 mm, with a wettest year of 176 mm.
A good time to visit Newcastle
September is a good time to visit Newcastle, with days averaging 19.9°C and nights around 13.9°C (mean 16.9°C, cooler than Newcastle'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 | 20.5°C | 17.5°C | 14.5°C | 24.4°C | 11.0°C | 47 mm | 73% | 2.7 m/s | 5.2 |
| 2024 | 21.4°C | 18.2°C | 14.9°C | 26.0°C | 11.4°C | 38 mm | 62% | 3 m/s | 5 |
| 2023 | 22.1°C | 18.4°C | 14.7°C | 28.5°C | 11.4°C | 10 mm | 65% | 2.4 m/s | 5.5 |
| 2022 | 18.5°C | 16.5°C | 14.4°C | 20.7°C | 11.4°C | 83 mm | 76% | 3.3 m/s | 4.2 |
| 2021 | 20.4°C | 17.2°C | 13.9°C | 25.4°C | 10.9°C | 29 mm | 66% | 3.2 m/s | 5.1 |
| 2020 | 20.7°C | 17.6°C | 14.6°C | 26.5°C | 10.3°C | 28 mm | 69% | 2.8 m/s | 5 |
| 2019 | 20.2°C | 17.2°C | 14.3°C | 26.4°C | 11.9°C | 61 mm | 69% | 3 m/s | 5.3 |
| 2018 | 19.9°C | 17.0°C | 14.0°C | 26.7°C | 11.5°C | 37 mm | 68% | 2.9 m/s | 4.9 |
| 2017 | 22.3°C | 18.4°C | 14.5°C | 29.3°C | 11.2°C | 2 mm | 54% | 2.9 m/s | 5.7 |
| 2016 | 20.0°C | 17.3°C | 14.6°C | 22.0°C | 11.9°C | 62 mm | 70% | 3.2 m/s | 4.6 |
| 2015 | 19.3°C | 16.7°C | 14.2°C | 24.6°C | 10.9°C | 48 mm | 70% | 3.2 m/s | 4.8 |
| 2014 | 19.2°C | 16.5°C | 13.9°C | 26.1°C | 10.7°C | 50 mm | 72% | 3 m/s | 5 |
| 2013 🔥 | 22.9°C | 19.4°C | 15.9°C | 29.0°C | 12.9°C | 30 mm | 63% | 2.7 m/s | 5.4 |
| 2012 | 20.5°C | 17.0°C | 13.5°C | 26.7°C | 10.2°C | 25 mm | 66% | 2.7 m/s | 5.6 |
| 2011 | 19.2°C | 16.5°C | 13.8°C | 24.4°C | 10.7°C | 110 mm | 72% | 3.2 m/s | 5 |
| 2010 | 19.9°C | 17.0°C | 14.0°C | 24.1°C | 10.4°C | 29 mm | 69% | 2.7 m/s | 4.7 |
| 2009 | 21.4°C | 18.1°C | 14.8°C | 26.8°C | 11.7°C | 28 mm | 64% | 2.9 m/s | 5.2 |
| 2008 | 19.3°C | 16.6°C | 13.9°C | 25.5°C | 10.1°C | 132 mm | 74% | 3.1 m/s | 5 |
| 2007 | 18.7°C | 16.3°C | 13.9°C | 23.5°C | 11.4°C | 39 mm | 73% | 3 m/s | 5.1 |
| 2006 | 20.4°C | 17.6°C | 14.7°C | 27.0°C | 12.5°C | 139 mm | 72% | 3.1 m/s | 4.9 |
| 2005 | 20.0°C | 17.0°C | 13.9°C | 25.2°C | 11.0°C | 51 mm | 69% | 3 m/s | 4.8 |
| 2004 | 19.9°C | 16.9°C | 13.9°C | 28.0°C | 9.8°C | 85 mm | 70% | 2.6 m/s | 4.9 |
| 2003 | 20.9°C | 17.6°C | 14.3°C | 29.1°C | 10.9°C | 4 mm | 59% | 3.1 m/s | 5.4 |
| 2002 | 21.0°C | 17.6°C | 14.2°C | 27.5°C | 10.5°C | 48 mm | 65% | 2.9 m/s | 5 |
| 2001 | 20.4°C | 17.6°C | 14.8°C | 25.3°C | 12.5°C | 39 mm | 73% | 3.1 m/s | 4.6 |
| 2000 | 21.7°C | 18.2°C | 14.6°C | 29.3°C | 11.5°C | 30 mm | 66% | 2.7 m/s | 5.2 |
| 1999 | 19.1°C | 16.6°C | 14.2°C | 23.1°C | 11.0°C | 49 mm | 77% | 2.8 m/s | 4.6 |
| 1998 | 19.9°C | 17.6°C | 15.2°C | 26.0°C | 10.9°C | 86 mm | 79% | 3 m/s | 4.4 |
| 1997 | 18.7°C | 16.3°C | 13.9°C | 22.9°C | 12.0°C | 78 mm | 75% | 3 m/s | 4.3 |
| 1996 | 19.6°C | 16.4°C | 13.2°C | 25.5°C | 10.3°C | 69 mm | 68% | 3.4 m/s | 4.8 |
| 1995 | 18.5°C | 15.9°C | 13.4°C | 24.1°C | 9.1°C | 136 mm | 74% | 3 m/s | 4.2 |
| 1994 | 20.1°C | 16.4°C | 12.8°C | 24.3°C | 10.0°C | 19 mm | 60% | 3 m/s | 5.5 |
| 1993 | 18.3°C | 15.7°C | 13.1°C | 23.0°C | 9.6°C | 73 mm | 73% | 3 m/s | 4.8 |
| 1992 | 18.5°C | 15.2°C | 12.0°C | 23.0°C | 8.8°C | 31 mm | 66% | 3.2 m/s | 4.8 |
| 1991 | 20.1°C | 16.6°C | 13.1°C | 24.1°C | 9.2°C | 12 mm | 61% | 3.1 m/s | 5.5 |
| 1990 ❄️ | 17.0°C | 14.8°C | 12.6°C | 21.1°C | 10.1°C | 96 mm | 78% | 3 m/s | 4.5 |
| 1989 | 18.6°C | 15.7°C | 12.9°C | 24.1°C | 8.6°C | 18 mm | 71% | 3.2 m/s | 5.2 |
| 1988 | 19.6°C | 17.1°C | 14.6°C | 23.6°C | 11.8°C | 113 mm | 75% | 3.1 m/s | 4.6 |
| 1987 | 19.3°C | 15.8°C | 12.4°C | 25.8°C | 7.6°C | 21 mm | 72% | 2.6 m/s | 5.4 |
| 1986 | 19.2°C | 16.4°C | 13.6°C | 25.2°C | 9.5°C | 74 mm | 72% | 2.8 m/s | 4.8 |
| 1985 | 17.8°C | 15.3°C | 12.7°C | 22.9°C | 9.9°C | 78 mm | 74% | 2.8 m/s | 5 |
| 1984 | 18.6°C | 15.3°C | 12.1°C | 23.1°C | 10.2°C | 33 mm | 67% | 3.2 m/s | 4.9 |
| 1983 | 20.2°C | 16.9°C | 13.6°C | 25.7°C | 10.8°C | 43 mm | 69% | 2.6 m/s | — |
| 1982 🌧️ | 18.9°C | 16.0°C | 13.1°C | 24.7°C | 7.9°C | 176 mm | 67% | 3.3 m/s | — |
| 1981 | 21.4°C | 17.7°C | 14.0°C | 27.3°C | 9.8°C | 14 mm | 66% | 2.5 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 19.9°C with lows near 13.9°C (mean 16.9°C), based on 45 years of NASA POWER data.
September averages 56 mm of rainfall in Newcastle, one of the drier months. The wettest on record was 176 mm in 1982.
The hottest September reached 29.3°C in 2000. The coldest dipped to 7.6°C in 1987.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.4°C. Daytime highs moved from 19.4°C to 20.6°C and overnight lows from 13.1°C to 14.5°C over the same span.
September is one of the cooler months of the year in Newcastle and one of the drier months, so plan for around 19.9°C daytime highs and 13.9°C at night.
Not quite — September is the 4th coolest month in Newcastle, averaging 16.9°C.
For September in Newcastle, pack light layers you can adjust through the day, with typical highs of 19.9°C and lows of 13.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 69% — moderately humid.
Average wind speed in September is 3 m/s. The windiest September on record averaged 3.4 m/s (1996).
The wettest September on record was 1982 with 176 mm. On average, September sees 56 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 Newcastle 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.
