January is one of the warmer months of the year in Onslow, with average highs near 31.8°C and lows around 26.3°C (mean 29.1°C). It is a relatively wet time of year, averaging 38 mm of rainfall and 67% relative humidity across the period.
January is one of the warmer months of the year in Onslow. Across 45 years of records, the warmest January in Onslow was 2025 — when the month averaged 31.1°C — while the coldest was 2016 at 27°C. Typical January days reach 31.8°C with nights near 26.3°C. The long-term January temperature trend is broadly flat.
January is a relatively wet time of year in Onslow, averaging 38 mm of rainfall. The wettest January on record was 2009 with 214 mm, while the driest was 2002 at 0 mm.
Relative humidity in Onslow during January averages 67%. The most humid January was 2011 at 76%, and the least humid was 2003 at 58%.
January receives about 7.7 kWh/m²/day of solar energy in Onslow. The sunniest Januarys were 1992 and 2002 at 8.3 kWh/m²/day, and the cloudiest was 2006 at 6.5.
Average wind speed in Onslow during January is 5 m/s. The windiest January was 2007 at 6.3 m/s, while the calmest was 1994 at 4 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 29.1°C | 28.9°C | 28.9°C | 29.0°C | 29.6°C | +0.5°C |
| Avg High | 31.9°C | 31.8°C | 31.7°C | 31.5°C | 32.3°C | +0.4°C |
| Avg Low | 26.2°C | 26.0°C | 26.0°C | 26.6°C | 27.0°C | +0.8°C |
| Avg Rain | 25 mm | 30 mm | 46 mm | 52 mm | 33 mm | +8 mm |
January temperatures in Onslow have risen by about 0.3°C between 1981–1985 and 2021–2025.
January has ranged from a record low of 21.5°C (2007) to a record high of 41°C (2022).
Rainfall in January is a relatively wet time of year, averaging 38 mm, with a wettest year of 214 mm.
Daytime highs and overnight lows have shifted differently — highs rose about 0°C per decade while lows rose 0.2°C per decade, narrowing the gap between day and night.
A quieter season to visit Onslow
If your dates are flexible, the more temperate months of September and August tend to be the most comfortable for visiting Onslow. That said, January — with days averaging 31.8°C and nights around 26.3°C (mean 29.1°C) and moderate rainfall (38 mm) — can still be rewarding for travellers who don't mind the warmth, and often means fewer crowds.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 🔥 | 33.2°C | 31.1°C | 29.0°C | 36.3°C | 26.9°C | 165 mm | 69% | 4.5 m/s | 6.6 |
| 2024 | 31.1°C | 28.0°C | 25.0°C | 37.0°C | 23.4°C | 0 mm | 67% | 5.8 m/s | 7.7 |
| 2023 | 31.5°C | 28.8°C | 26.1°C | 38.9°C | 24.1°C | 16 mm | 68% | 5.3 m/s | 7.6 |
| 2022 | 31.6°C | 29.0°C | 26.5°C | 41.0°C | 24.5°C | 0 mm | 68% | 5.2 m/s | 7.8 |
| 2021 | 33.8°C | 30.9°C | 28.1°C | 39.0°C | 24.0°C | 11 mm | 61% | 5.1 m/s | 7.8 |
| 2020 | 32.6°C | 29.9°C | 27.2°C | 35.0°C | 22.9°C | 5 mm | 65% | 5.3 m/s | 7.5 |
| 2019 | 32.6°C | 29.8°C | 27.0°C | 38.5°C | 24.5°C | 18 mm | 64% | 4.9 m/s | 7.7 |
| 2018 | 32.6°C | 30.0°C | 27.3°C | 36.3°C | 24.4°C | 22 mm | 68% | 4.7 m/s | 7.5 |
| 2017 | 30.9°C | 28.3°C | 25.8°C | 37.1°C | 23.4°C | 30 mm | 69% | 5.8 m/s | 7.3 |
| 2016 ❄️ | 29.3°C | 27.0°C | 24.7°C | 32.1°C | 23.0°C | 12 mm | 70% | 5.1 m/s | 7.1 |
| 2015 | 31.2°C | 28.8°C | 26.4°C | 37.1°C | 24.4°C | 13 mm | 70% | 5.1 m/s | 7.8 |
| 2014 | 32.4°C | 29.5°C | 26.6°C | 39.5°C | 24.0°C | 52 mm | 66% | 5 m/s | 7.5 |
| 2013 | 32.7°C | 30.5°C | 28.2°C | 36.9°C | 26.6°C | 88 mm | 70% | 4.6 m/s | 7.1 |
| 2012 | 30.2°C | 28.3°C | 26.4°C | 33.0°C | 23.4°C | 133 mm | 74% | 5.1 m/s | 7.1 |
| 2011 | 31.6°C | 29.9°C | 28.2°C | 34.4°C | 27.1°C | 125 mm | 76% | 4.4 m/s | 6.8 |
| 2010 | 31.0°C | 28.2°C | 25.4°C | 36.3°C | 23.1°C | 31 mm | 69% | 5.6 m/s | 7.9 |
| 2009 🌧️ | 32.2°C | 29.5°C | 26.9°C | 37.0°C | 24.1°C | 214 mm | 70% | 4.6 m/s | 7.4 |
| 2008 | 32.7°C | 30.0°C | 27.2°C | 39.4°C | 24.6°C | 5 mm | 66% | 4.7 m/s | 7.8 |
| 2007 | 31.8°C | 28.5°C | 25.1°C | 34.9°C | 21.5°C | 0 mm | 62% | 6.3 m/s | 8 |
| 2006 | 30.1°C | 27.6°C | 25.2°C | 35.3°C | 22.7°C | 55 mm | 71% | 5.8 m/s | 6.5 |
| 2005 | 33.0°C | 29.7°C | 26.5°C | 36.0°C | 24.7°C | 1 mm | 65% | 4.6 m/s | 7.8 |
| 2004 | 31.8°C | 28.5°C | 25.2°C | 34.5°C | 23.2°C | 47 mm | 67% | 5.1 m/s | 7.7 |
| 2003 | 33.5°C | 30.3°C | 27.1°C | 39.0°C | 24.8°C | 2 mm | 58% | 4.6 m/s | 7.8 |
| 2002 | 30.1°C | 27.4°C | 24.7°C | 34.7°C | 22.7°C | 0 mm | 68% | 4.8 m/s | 8.3 |
| 2001 | 31.9°C | 29.2°C | 26.6°C | 35.3°C | 24.1°C | 106 mm | 67% | 4.2 m/s | 7.4 |
| 2000 | 30.1°C | 27.9°C | 25.7°C | 32.9°C | 23.3°C | 25 mm | 70% | 4.7 m/s | 7.7 |
| 1999 | 32.0°C | 29.3°C | 26.7°C | 37.3°C | 22.7°C | 9 mm | 65% | 4.9 m/s | 7.8 |
| 1998 | 32.2°C | 29.0°C | 25.7°C | 37.7°C | 23.1°C | 3 mm | 65% | 4.9 m/s | 7.9 |
| 1997 | 32.0°C | 29.9°C | 27.7°C | 36.1°C | 25.3°C | 82 mm | 72% | 4.3 m/s | 7.3 |
| 1996 | 31.9°C | 28.6°C | 25.3°C | 36.6°C | 23.0°C | 1 mm | 64% | 5.2 m/s | 8 |
| 1995 | 31.4°C | 28.6°C | 25.8°C | 35.9°C | 23.4°C | 6 mm | 67% | 5.3 m/s | 7.9 |
| 1994 | 32.6°C | 29.7°C | 26.8°C | 36.7°C | 25.2°C | 7 mm | 64% | 4 m/s | 8.1 |
| 1993 | 31.8°C | 28.8°C | 25.8°C | 36.8°C | 23.9°C | 26 mm | 66% | 4.4 m/s | 7.9 |
| 1992 | 30.1°C | 27.2°C | 24.4°C | 33.1°C | 21.8°C | 7 mm | 69% | 5 m/s | 8.3 |
| 1991 | 32.7°C | 29.2°C | 25.7°C | 35.7°C | 24.4°C | 3 mm | 61% | 5.9 m/s | 8.2 |
| 1990 | 31.2°C | 28.6°C | 26.0°C | 34.6°C | 22.0°C | 152 mm | 70% | 5.3 m/s | 7.3 |
| 1989 | 32.1°C | 29.3°C | 26.5°C | 35.2°C | 23.6°C | 6 mm | 63% | 5.2 m/s | 7.9 |
| 1988 | 32.3°C | 29.1°C | 25.9°C | 36.6°C | 22.8°C | 3 mm | 62% | 4.9 m/s | 8.2 |
| 1987 | 31.1°C | 28.2°C | 25.4°C | 36.6°C | 22.8°C | 29 mm | 64% | 5.5 m/s | 7.7 |
| 1986 | 31.0°C | 28.6°C | 26.2°C | 35.2°C | 23.2°C | 16 mm | 69% | 4.3 m/s | 8 |
| 1985 | 32.6°C | 29.2°C | 25.8°C | 38.2°C | 21.8°C | 20 mm | 61% | 4.9 m/s | 7.8 |
| 1984 | 32.4°C | 29.5°C | 26.7°C | 35.6°C | 23.9°C | 6 mm | 64% | 4.9 m/s | 7.8 |
| 1983 | 32.4°C | 29.4°C | 26.5°C | 36.3°C | 24.1°C | 17 mm | 64% | 4.8 m/s | — |
| 1982 | 31.7°C | 29.0°C | 26.2°C | 35.7°C | 23.0°C | 107 mm | 68% | 5 m/s | — |
| 1981 | 31.9°C | 29.3°C | 26.7°C | 36.8°C | 24.6°C | 16 mm | 69% | 4.9 m/s | — |
Actual recorded January data for each year, 1981–2025 — sourced from NASA POWER.
The average high in January is around 31.8°C with lows near 26.3°C (mean 29.1°C), based on 45 years of NASA POWER data.
January averages 38 mm of rainfall in Onslow, a relatively wet time of year. The wettest on record was 214 mm in 2009.
The hottest January reached 41°C in 2022. The coldest dipped to 21.5°C in 2007.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 0.3°C. Daytime highs moved from 32.2°C to 32.2°C and overnight lows from 26.4°C to 26.9°C over the same span.
January is one of the warmer months of the year in Onslow and a relatively wet time of year, so plan for around 31.8°C daytime highs and 26.3°C at night.
Not quite — January is the 10th coolest month in Onslow, averaging 29.1°C.
For January in Onslow, pack light, breathable clothing and sun protection, with typical highs of 31.8°C and lows of 26.3°C.
Relative humidity in January averages 67% — moderately humid.
Average wind speed in January is 5 m/s. The windiest January on record averaged 6.3 m/s (2007).
The wettest January on record was 2009 with 214 mm. On average, January sees 38 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 Onslow behaves each January, 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 January specifically, along with year-by-year records and how the month has changed over the decades.
