January is one of the warmer months of the year in Horsham, with average highs near 31.8°C and lows around 14.5°C (mean 23.2°C). It is about average for rainfall, averaging 29 mm of rainfall and 45% relative humidity across the period.
January is one of the warmer months of the year in Horsham. Across 45 years of records, the warmest January in Horsham was 1981 — when the month averaged 26.4°C — while the coldest was 1987 at 19.8°C. Typical January days reach 31.8°C with nights near 14.5°C. The long-term trend is warming, about 0.4°C per decade.
January is about average for rainfall in Horsham, averaging 29 mm of rainfall. The wettest January on record was 2011 with 167 mm, while the driest was 2009 at 1 mm.
Relative humidity in Horsham during January averages 45%. The most humid January was 2011 at 63%, and the least humid were 2009 and 2019 at 36%.
January receives about 7.8 kWh/m²/day of solar energy in Horsham. The sunniest January was 2009 at 8.7 kWh/m²/day, and the cloudiest was 2015 at 7.2.
Average wind speed in Horsham during January is 3.9 m/s. The windiest January was 1990 at 4.6 m/s, while the calmest was 2011 at 3.2 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 22.3°C | 22.8°C | 23.2°C | 23.9°C | 23.6°C | +1.3°C |
| Avg High | 31.2°C | 31.3°C | 31.9°C | 32.6°C | 31.9°C | +0.7°C |
| Avg Low | 13.6°C | 14.2°C | 14.6°C | 15.3°C | 15.2°C | +1.6°C |
| Avg Rain | 23 mm | 25 mm | 24 mm | 37 mm | 41 mm | +18 mm |
January temperatures in Horsham have risen by about 0.8°C between 1981–1985 and 2021–2025.
January has ranged from a record low of 6.3°C (1987) to a record high of 46.7°C (1982).
Rainfall in January is about average for rainfall, averaging 29 mm, with a wettest year of 167 mm.
One of the best times to visit Horsham
January is one of the best times to visit Horsham. Expect days averaging 31.8°C and nights around 14.5°C (mean 23.2°C) — warmer than Horsham's yearly average — with low rainfall (29 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 | 32.8°C | 24.3°C | 15.7°C | 41.9°C | 10.3°C | 14 mm | 41% | 3.7 m/s | 7.7 |
| 2024 | 30.1°C | 22.5°C | 14.9°C | 35.5°C | 10.5°C | 74 mm | 59% | 3.4 m/s | 7.5 |
| 2023 | 31.9°C | 23.2°C | 14.5°C | 39.5°C | 10.0°C | 14 mm | 48% | 3.5 m/s | 7.9 |
| 2022 | 33.8°C | 25.7°C | 17.7°C | 38.0°C | 11.9°C | 54 mm | 47% | 3.7 m/s | 7.7 |
| 2021 | 31.1°C | 22.7°C | 14.2°C | 40.9°C | 10.0°C | 51 mm | 49% | 4.1 m/s | 7.7 |
| 2020 | 31.9°C | 23.0°C | 14.0°C | 41.6°C | 9.6°C | 38 mm | 44% | 3.7 m/s | 7.7 |
| 2019 | 35.9°C | 26.3°C | 16.6°C | 44.7°C | 10.5°C | 2 mm | 36% | 3.6 m/s | 8.2 |
| 2018 | 34.3°C | 25.2°C | 16.2°C | 44.6°C | 9.1°C | 15 mm | 39% | 3.7 m/s | 7.8 |
| 2017 | 32.1°C | 23.7°C | 15.3°C | 41.7°C | 10.0°C | 41 mm | 45% | 3.6 m/s | 7.8 |
| 2016 | 32.5°C | 24.5°C | 16.6°C | 42.8°C | 11.2°C | 46 mm | 43% | 3.5 m/s | 7.3 |
| 2015 | 30.7°C | 22.6°C | 14.6°C | 42.7°C | 9.1°C | 57 mm | 50% | 4 m/s | 7.2 |
| 2014 | 34.1°C | 25.0°C | 16.0°C | 45.3°C | 8.3°C | 15 mm | 39% | 4.1 m/s | 8 |
| 2013 | 32.9°C | 23.5°C | 14.2°C | 43.4°C | 9.9°C | 6 mm | 37% | 4 m/s | 8.4 |
| 2012 | 32.2°C | 23.9°C | 15.7°C | 41.5°C | 8.0°C | 12 mm | 43% | 4.4 m/s | 8 |
| 2011 🌧️ | 28.8°C | 21.5°C | 14.1°C | 39.1°C | 9.0°C | 167 mm | 63% | 3.2 m/s | 7.6 |
| 2010 | 32.4°C | 23.1°C | 13.9°C | 44.0°C | 8.7°C | 8 mm | 40% | 3.8 m/s | 8.1 |
| 2009 | 33.5°C | 23.9°C | 14.3°C | 44.5°C | 6.8°C | 1 mm | 36% | 3.5 m/s | 8.7 |
| 2008 | 32.5°C | 23.9°C | 15.2°C | 43.0°C | 9.6°C | 38 mm | 45% | 3.8 m/s | 7.9 |
| 2007 | 30.9°C | 22.9°C | 15.0°C | 41.0°C | 9.7°C | 67 mm | 53% | 4 m/s | 7.5 |
| 2006 | 33.9°C | 25.2°C | 16.5°C | 43.8°C | 10.8°C | 33 mm | 43% | 3.8 m/s | 7.7 |
| 2005 | 31.0°C | 22.6°C | 14.2°C | 41.9°C | 7.8°C | 39 mm | 47% | 3.7 m/s | 7.6 |
| 2004 | 28.5°C | 20.3°C | 12.1°C | 40.1°C | 7.8°C | 10 mm | 47% | 4 m/s | 7.7 |
| 2003 | 32.7°C | 23.3°C | 14.0°C | 44.9°C | 8.7°C | 8 mm | 41% | 4.1 m/s | 7.9 |
| 2002 | 29.9°C | 21.3°C | 12.6°C | 39.8°C | 8.3°C | 15 mm | 45% | 3.9 m/s | 7.4 |
| 2001 | 35.1°C | 26.3°C | 17.5°C | 45.5°C | 10.5°C | 26 mm | 40% | 3.9 m/s | 7.3 |
| 2000 | 30.5°C | 22.4°C | 14.4°C | 42.4°C | 8.5°C | 3 mm | 43% | 4 m/s | 7.7 |
| 1999 | 35.2°C | 25.9°C | 16.6°C | 43.4°C | 11.7°C | 12 mm | 40% | 3.7 m/s | 8 |
| 1998 | 31.5°C | 23.1°C | 14.8°C | 43.3°C | 10.5°C | 20 mm | 45% | 3.9 m/s | 7.5 |
| 1997 | 32.5°C | 23.4°C | 14.4°C | 42.0°C | 8.9°C | 31 mm | 41% | 4.1 m/s | 7.6 |
| 1996 | 30.4°C | 21.9°C | 13.4°C | 41.8°C | 9.7°C | 14 mm | 45% | 4.1 m/s | 7.8 |
| 1995 | 32.3°C | 24.2°C | 16.1°C | 40.3°C | 8.9°C | 21 mm | 43% | 3.9 m/s | 7.6 |
| 1994 | 28.8°C | 20.3°C | 11.7°C | 40.9°C | 7.1°C | 29 mm | 48% | 4.4 m/s | 7.5 |
| 1993 | 30.1°C | 22.0°C | 13.8°C | 39.6°C | 8.2°C | 75 mm | 59% | 3.4 m/s | 7.6 |
| 1992 | 28.2°C | 20.2°C | 12.2°C | 39.1°C | 7.8°C | 8 mm | 48% | 4.1 m/s | 7.8 |
| 1991 | 32.0°C | 23.4°C | 14.8°C | 42.4°C | 9.5°C | 41 mm | 48% | 4 m/s | 7.6 |
| 1990 | 32.2°C | 23.4°C | 14.5°C | 42.1°C | 8.7°C | 5 mm | 40% | 4.6 m/s | 8.1 |
| 1989 | 30.9°C | 22.4°C | 13.9°C | 39.1°C | 8.5°C | 13 mm | 43% | 4.3 m/s | 7.9 |
| 1988 | 32.6°C | 23.8°C | 15.0°C | 41.6°C | 9.0°C | 31 mm | 43% | 3.6 m/s | 7.8 |
| 1987 ❄️ | 28.4°C | 19.8°C | 11.2°C | 38.4°C | 6.3°C | 33 mm | 49% | 3.9 m/s | 7.8 |
| 1986 | 29.2°C | 20.5°C | 11.7°C | 40.0°C | 8.7°C | 6 mm | 46% | 4.1 m/s | 8.2 |
| 1985 | 31.2°C | 22.1°C | 13.0°C | 43.2°C | 8.2°C | 12 mm | 41% | 4.1 m/s | 7.8 |
| 1984 | 28.4°C | 20.2°C | 12.1°C | 35.3°C | 8.5°C | 52 mm | 54% | 4 m/s | 7.3 |
| 1983 | 30.4°C | 21.2°C | 12.1°C | 42.1°C | 7.3°C | 6 mm | 38% | 3.9 m/s | — |
| 1982 | 33.5°C | 24.7°C | 16.0°C | 46.7°C | 9.7°C | 26 mm | 40% | 4 m/s | — |
| 1981 🔥 | 35.9°C | 26.4°C | 17.0°C | 43.1°C | 11.0°C | 25 mm | 37% | 4.2 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 14.5°C (mean 23.2°C), based on 45 years of NASA POWER data.
January averages 29 mm of rainfall in Horsham, about average for rainfall. The wettest on record was 167 mm in 2011.
The hottest January reached 46.7°C in 1982. The coldest dipped to 6.3°C in 1987.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average January temperatures have risen by about 0.8°C. Daytime highs moved from 31.9°C to 31.9°C and overnight lows from 14°C to 15.4°C over the same span.
January is one of the warmer months of the year in Horsham and about average for rainfall, so plan for around 31.8°C daytime highs and 14.5°C at night.
Not quite — January is the 12th coolest month in Horsham, averaging 23.2°C.
For January in Horsham, pack light, breathable clothing and sun protection, with typical highs of 31.8°C and lows of 14.5°C.
Relative humidity in January averages 45% — relatively dry.
Average wind speed in January is 3.9 m/s. The windiest January on record averaged 4.6 m/s (1990).
The wettest January on record was 2011 with 167 mm. On average, January sees 29 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 Horsham 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.
