St Mawes sits near the bottom of UK towns for frosts
A warm July spell here typically peaks at 20.1°C (68°F). The rainiest month is December; the driest is May. None of its 6 nearest neighbours gets less rain. Keep the boiler serviced for the months from December to April, which average under 10°C.
Met Office 1991–2020 averages for the town itself.
A year in St Mawes at a glance
Each month’s typical high and low, in °C.
What a year in St Mawes feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 1,021 mm of rain a year
December is the wettest month and May the driest. About 31 days a year bring 10 mm (0.4 in) or more.
Rain by month
Millimetres
Sunshine by month
Hours of bright sunshine at Camborne
6 air frosts and under 1 days of 25°C a year
On about 6 nights a year the air drops below freezing; days that stay below freezing are rare. About under 1 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 Camborne
Camborne is 15 miles west of St Mawes, 87 m (285 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 | 9.2°C | 4.9°C | 121 mm | 2.2 | 60 |
| February | 9.1°C | 4.6°C | 95 mm | 2.1 | 82 |
| March | 10.2°C | 5.4°C | 72 mm | 1.1 | 121 |
| April | 12.1°C | 6.6°C | 73 mm | 0.0 | 181 |
| May | 14.5°C | 8.8°C | 61 mm | 0.0 | 208 |
| June | 16.9°C | 11.2°C | 63 mm | 0.0 | 205 |
| July | 18.7°C | 13.2°C | 69 mm | 0.0 | 190 |
| August | 19.0°C | 13.4°C | 79 mm | 0.0 | 180 |
| September | 17.5°C | 12.0°C | 78 mm | 0.0 | 154 |
| October | 14.6°C | 10.0°C | 111 mm | 0.0 | 108 |
| November | 11.8°C | 7.4°C | 130 mm | 0.2 | 68 |
| December | 9.9°C | 5.6°C | 126 mm | 1.7 | 54 |
| Year | 13.6°C | 8.6°C | 1,076 mm | 7 | 1,611 |
Met Office historic station data, Camborne, 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Kipp & Zonen recorder.
How St Mawes 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 Cornwall 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 |
|---|---|---|---|
| St Mawes | 20.1°C | 4.6°C | 1,021 mm |
| Falmouth 3.0 mi | 19.8°C about the same | 4.8°C about the same | 1,216 mm |
| Mylor Bridge 3.3 mi | 20.5°C about the same | 4.3°C about the same | 1,147 mm |
| Penryn 4.6 mi | 19.6°C about the same | 4.2°C about the same | 1,322 mm |
| Carnon Downs and Devoran 5.3 mi | 19.9°C about the same | 4.2°C about the same | 1,193 mm |
| Mawnan Smith 5.4 mi | 19.7°C about the same | 4.6°C about the same | 1,215 mm |
| Perranarworthal 5.9 mi | 19.9°C about the same | 4.1°C 0.5°C colder | 1,199 mm |
St Mawes 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 | 10.3°C 51°F | 4.6°C 40°F | 7.4°C | 111 mm 4.4 in |
| February | 10.5°C 51°F | 4.6°C 40°F | 7.5°C | 92 mm 3.6 in |
| March | 11.7°C 53°F | 5.1°C 41°F | 8.3°C | 73 mm 2.9 in |
| April | 13.4°C 56°F | 5.9°C 43°F | 9.7°C | 66 mm 2.6 in |
| May | 16.1°C 61°F | 8.3°C 47°F | 12.1°C | 55 mm 2.2 in |
| June | 18.4°C 65°F | 10.8°C 51°F | 14.6°C | 60 mm 2.4 in |
| July | 20.1°C 68°F | 12.6°C 55°F | 16.3°C | 76 mm 3.0 in |
| August | 20.4°C 69°F | 12.7°C 55°F | 16.5°C | 77 mm 3.0 in |
| September | 19.0°C 66°F | 11.6°C 53°F | 15.4°C | 67 mm 2.7 in |
| October | 16.1°C 61°F | 9.8°C 50°F | 12.9°C | 102 mm 4.0 in |
| November | 13.3°C 56°F | 7.0°C 45°F | 10.2°C | 120 mm 4.7 in |
| December | 11.3°C 52°F | 5.7°C 42°F | 8.4°C | 122 mm 4.8 in |
| Year | 15.1°C | 8.2°C | 11.6°C | 1,021 mm |
Where St Mawes’s numbers come from
Averages over 30 years, not a forecast.
- Mean temperature, rain and day counts: HadUK-Grid 1991–2020 averages for the Met Office 2 km grid square nearest St Mawes’s centre (the town is smaller than one square).
- 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 Camborne, 15 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 St Mawes’s climate
How warm does St Mawes get in summer?
August is the warmest month, with average highs of 20.4°C (69°F). About under 1 days a year reach 25°C (77°F), fewer than almost every UK town.
How cold does St Mawes get in winter?
January nights average 4.6°C (40°F). The air drops below freezing on about 6 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does St Mawes get?
About 1,021 mm (40 in) a year, more than 79% of UK towns. December is the wettest month (122 mm) and May the driest (55 mm).
How sunny is it?
The nearest Met Office station with a sunshine record, Camborne (15 miles away), averages 1,611 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 St Mawes. 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 St Mawes →
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.