Photo: The Voice of Hassocks · Public domainWinter nights in Southwick are milder than in 91% of UK towns
On a normal July day the thermometer tops out near 21.9°C (71°F). From frosty January to warm July, readings climb 20°C. By rainfall alone, it ranks wetter than 67% of UK towns. The heating season runs November to April: each of those months averages under 10°C.
Met Office 1991–2020 averages for the town itself.
A year in Southwick at a glance
Each month’s typical high and low, in °C.
What a year in Southwick feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 881 mm of rain a year
December is the wettest month and April the driest. About 24 days a year bring 10 mm (0.4 in) or more. 8th wettest of 40 West Sussex towns of 2,500+.
Rain by month
Millimetres
Sunshine by month
Hours of bright sunshine at Eastbourne
28 air frosts and 7 days of 25°C a year
On about 28 nights a year the air drops below freezing, and on about under 1 days it stays below freezing all day. About 7 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 Eastbourne
Eastbourne is 23 miles east of Southwick, 7 m (23 ft) above sea level. It is the nearest of the 37 long-running stations the Met Office publishes in full.
| Month | High | Low | Rain | Air frosts | Sun (hours) |
|---|---|---|---|---|---|
| January | 8.5°C | 3.9°C | 83 mm | 4.5 | 70 |
| February | 8.6°C | 3.6°C | 58 mm | 3.8 | 90 |
| March | 10.5°C | 4.9°C | 48 mm | 1.1 | 134 |
| April | 13.3°C | 6.7°C | 45 mm | 0.2 | 203 |
| May | 16.3°C | 9.6°C | 46 mm | 0.0 | 236 |
| June | 18.9°C | 12.5°C | 47 mm | 0.0 | 239 |
| July | 21.0°C | 14.7°C | 54 mm | 0.0 | 252 |
| August | 21.3°C | 14.9°C | 60 mm | 0.0 | 233 |
| September | 19.2°C | 12.6°C | 60 mm | 0.0 | 172 |
| October | 15.7°C | 9.9°C | 93 mm | 0.0 | 121 |
| November | 11.9°C | 6.9°C | 98 mm | 0.6 | 78 |
| December | 9.3°C | 4.5°C | 100 mm | 3.8 | 62 |
| Year | 14.5°C | 8.7°C | 792 mm | 14 | 1,889 |
Met Office historic station data, Eastbourne, 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Campbell-Stokes recorder.
How Southwick 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 |
|---|---|---|---|
| Southwick | 21.9°C | 2.8°C | 881 mm |
| Shoreham-by-Sea 1.6 mi | 22.1°C about the same | 2.8°C about the same | 838 mm |
| Brighton and Hove 3.8 mi | 21.2°C 0.7°C cooler | 3.1°C about the same | 832 mm |
| Lancing and Sompting 4.2 mi | 22.1°C about the same | 2.5°C about the same | 756 mm |
| Upper Beeding 4.4 mi | 22.2°C about the same | 2.5°C about the same | 878 mm |
| Steyning 5.5 mi | 22.2°C about the same | 2.2°C 0.6°C colder | 876 mm |
| Henfield 6.9 mi | 22.2°C about the same | 2.2°C 0.6°C colder | 860 mm |
Southwick 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 | 8.8°C 48°F | 2.8°C 37°F | 5.7°C | 88 mm 3.4 in |
| February | 8.6°C 47°F | 1.9°C 35°F | 5.2°C | 67 mm 2.6 in |
| March | 10.9°C 52°F | 3.3°C 38°F | 7.0°C | 56 mm 2.2 in |
| April | 13.9°C 57°F | 4.8°C 41°F | 9.3°C | 51 mm 2.0 in |
| May | 17.0°C 63°F | 7.6°C 46°F | 12.4°C | 51 mm 2.0 in |
| June | 19.9°C 68°F | 10.5°C 51°F | 15.3°C | 56 mm 2.2 in |
| July | 21.9°C 71°F | 12.5°C 54°F | 17.2°C | 59 mm 2.3 in |
| August | 22.2°C 72°F | 12.7°C 55°F | 17.4°C | 68 mm 2.7 in |
| September | 19.7°C 68°F | 10.6°C 51°F | 15.1°C | 69 mm 2.7 in |
| October | 15.9°C 61°F | 8.2°C 47°F | 12.0°C | 104 mm 4.1 in |
| November | 11.7°C 53°F | 5.2°C 41°F | 8.5°C | 106 mm 4.2 in |
| December | 9.0°C 48°F | 2.9°C 37°F | 5.9°C | 108 mm 4.3 in |
| Year | 14.9°C | 6.9°C | 10.9°C | 881 mm |
Where Southwick’s numbers come from
Averages over 30 years, not a forecast.
- Mean temperature, rain and day counts: HadUK-Grid 1991–2020 averages for the 1 Met Office 2 km grid square whose centre lies inside Southwick’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 Eastbourne, 23 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 Southwick’s climate
How warm does Southwick get in summer?
August is the warmest month, with average highs of 22.2°C (72°F). About 7 days a year reach 25°C (77°F), fewer than 67% of UK towns.
How cold does Southwick get in winter?
February nights average 1.9°C (35°F). The air drops below freezing on about 28 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Southwick get?
About 881 mm (35 in) a year, more than 67% of UK towns. December is the wettest month (108 mm) and April the driest (51 mm).
How sunny is it?
The nearest Met Office station with a sunshine record, Eastbourne (23 miles away), averages 1,889 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 Southwick. 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 Southwick →
Contains public sector information licensed under the Open Government Licence v3.0. Contains HM Land Registry data © Crown copyright and database right 2026. Contains OS data © Crown copyright and database right 2026 (ONS boundaries). Northern Ireland: Source: NISRA; contains Land & Property Services data and Ordnance Survey of Northern Ireland information, © Crown copyright, licensed under the Open Government Licence v3.0. Scotland: contains National Records of Scotland data, Registers of Scotland data and SEPA data, © Crown copyright / © SEPA 2025, licensed under the Open Government Licence v3.0.