Horsham gets more days of 25 degrees or more than 84% of UK towns
The depth of winter brings overnight lows near 1.9°C (35°F). Of all months, November brings the most rain and April the least. By frosts alone, it ranks colder than 73% of UK towns. Expect about 46 frosty starts a year, nights when the air falls below freezing.
Met Office 1991–2020 averages for the town itself.
A year in Horsham at a glance
Each month’s typical high and low, in °C.
What a year in Horsham feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 830 mm of rain a year
November is the wettest month and April the driest. About 25 days a year bring 10 mm (0.4 in) or more. 23rd wettest of 40 West Sussex towns of 2,500+.
Rain by month
Millimetres
Sunshine by month
Hours of bright sunshine at Heathrow
46 air frosts and 18 days of 25°C a year
On about 46 nights a year the air drops below freezing, and on about under 1 days it stays below freezing all day. About 18 days a year reach 25°C (77°F).
Day counts are 1991–2020 averages from the Met Office’s 2 km grid. The Met Office calls a day of 25°C or more a summer day and a night below 0°C an air frost; ground frosts, on grass, come more often.
The Met Office station at Heathrow
Heathrow is 29 miles north of Horsham, 25 m (82 ft) above sea level. It is the nearest of the 37 long-running stations the Met Office publishes in full; at that distance read it for sunshine and the station’s own record, not as the town’s figures.
| Month | High | Low | Rain | Air frosts | Sun (hours) |
|---|---|---|---|---|---|
| January | 8.4°C | 2.7°C | 59 mm | 6.8 | 59 |
| February | 9.0°C | 2.6°C | 45 mm | 6.2 | 76 |
| March | 11.7°C | 4.1°C | 39 mm | 3.0 | 120 |
| April | 15.0°C | 6.0°C | 42 mm | 0.8 | 169 |
| May | 18.4°C | 9.1°C | 46 mm | 0.0 | 197 |
| June | 21.6°C | 12.0°C | 47 mm | 0.0 | 197 |
| July | 23.9°C | 14.2°C | 46 mm | 0.0 | 206 |
| August | 23.4°C | 14.1°C | 54 mm | 0.0 | 192 |
| September | 20.2°C | 11.6°C | 50 mm | 0.0 | 150 |
| October | 15.8°C | 8.8°C | 65 mm | 0.3 | 111 |
| November | 11.5°C | 5.3°C | 67 mm | 2.7 | 68 |
| December | 8.8°C | 3.1°C | 57 mm | 7.2 | 53 |
| Year | 15.6°C | 7.8°C | 616 mm | 27 | 1,597 |
Met Office historic station data, Heathrow (London Airport), 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Kipp & Zonen recorder.
How Horsham compares
Against the 2,537 towns and cities of 2,500 or more across the UK, each with its own Met Office averages, and its place among West Sussex towns that size.
Nearby towns’ climate
The nearest towns of 1,000+ within 12 miles: a hill, a valley or the sea can make a real difference over a few miles.
| Town | July high | January low | Rain a year |
|---|---|---|---|
| Horsham | 22.5°C | 1.9°C | 830 mm |
| Broadbridge Heath 2.0 mi | 22.9°C about the same | 2.0°C about the same | 835 mm |
| Mannings Heath 2.2 mi | 22.2°C about the same | 1.7°C about the same | 838 mm |
| Southwater 3.1 mi | 22.8°C about the same | 2.1°C about the same | 812 mm |
| Slinfold 3.8 mi | 22.7°C about the same | 2.1°C about the same | 826 mm |
| Barns Green 4.2 mi | 22.8°C about the same | 2.3°C about the same | 811 mm |
| Pease Pottage 5.0 mi | 22.3°C about the same | 1.4°C 0.5°C colder | 831 mm |
Horsham weather by month
Average daily high and low, mean temperature and rain, 1991–2020, for the town itself (the Met Office’s HadUK-Grid).
| Month | High | Low | Mean | Rain |
|---|---|---|---|---|
| January | 8.1°C 47°F | 1.9°C 35°F | 4.9°C | 92 mm 3.6 in |
| February | 8.6°C 47°F | 1.7°C 35°F | 5.1°C | 63 mm 2.5 in |
| March | 11.1°C 52°F | 3.1°C 38°F | 7.1°C | 53 mm 2.1 in |
| April | 14.2°C 58°F | 4.7°C 40°F | 9.4°C | 52 mm 2.0 in |
| May | 17.4°C 63°F | 7.4°C 45°F | 12.5°C | 54 mm 2.1 in |
| June | 20.3°C 68°F | 10.3°C 50°F | 15.3°C | 52 mm 2.1 in |
| July | 22.5°C 73°F | 12.4°C 54°F | 17.4°C | 53 mm 2.1 in |
| August | 22.4°C 72°F | 12.2°C 54°F | 17.2°C | 62 mm 2.5 in |
| September | 19.5°C 67°F | 9.9°C 50°F | 14.7°C | 63 mm 2.5 in |
| October | 15.4°C 60°F | 7.5°C 45°F | 11.4°C | 94 mm 3.7 in |
| November | 11.2°C 52°F | 4.3°C 40°F | 7.8°C | 100 mm 3.9 in |
| December | 8.5°C 47°F | 2.2°C 36°F | 5.3°C | 94 mm 3.7 in |
| Year | 14.9°C | 6.5°C | 10.7°C | 830 mm |
Where Horsham’s numbers come from
Averages over 30 years, not a forecast.
- Mean temperature, rain and day counts: HadUK-Grid 1991–2020 averages for the 3 Met Office 2 km grid squares whose centre lies inside Horsham’s built-up area.
- Highs and lows: the Met Office publishes average daily maxima and minima on its 12 km grid; each is moved by the difference between the town’s 2 km mean temperature and the 12 km square’s, which carries the town’s own height and setting over.
- Weather station and sunshine: Met Office historic station data for Heathrow (London Airport), 29 miles away, months of 1991–2020 averaged.
- Comparisons: every town and city of 2,500 or more across the UK, all four nations, read the same way.
Met Office HadUK-Grid · Met Office Climate Data Portal · Historic station data. Open Government Licence v3.0.
Questions about Horsham’s climate
How warm does Horsham get in summer?
July is the warmest month, with average highs of 22.5°C (73°F). About 18 days a year reach 25°C (77°F), more than 84% of UK towns.
How cold does Horsham get in winter?
February nights average 1.7°C (35°F). The air drops below freezing on about 46 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Horsham get?
About 830 mm (33 in) a year, more than 59% of UK towns. November is the wettest month (100 mm) and April the driest (52 mm).
How sunny is it?
The nearest Met Office station with a sunshine record, Heathrow (29 miles away), averages 1,597 hours of bright sunshine a year. Sunshine isn’t on the town grid, so this is the station’s figure.
Where do these figures come from?
The Met Office’s HadUK-Grid 1991–2020 averages, which turn thousands of weather stations into a map of the UK in 2 km squares; the page reads the squares inside Horsham. They are 30-year averages, not a forecast.
Contains Met Office data © Crown copyright 2026, Open Government Licence v3.0. HadUK-Grid 1991–2020 averages via the Met Office Climate Data Portal; station averages from Met Office historic station data. Today’s forecast for Horsham →
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