Porthleven sits near the top of UK towns for mild winters
The warmest part of a July day comes in at 19.4°C (67°F) on average. Winter and summer sit 15°C apart. By July afternoons alone, it runs cooler than 85% of UK towns. Frost greets about 10 mornings a year, so leave time to clear the car.
Met Office 1991–2020 averages for the town itself.
A year in Porthleven at a glance
Each month’s typical high and low, in °C.
What a year in Porthleven feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 1,067 mm of rain a year
November is the wettest month and May the driest. About 32 days a year bring 10 mm (0.4 in) or more. 28th wettest of 35 Cornwall towns of 2,500+.
Rain by month
Millimetres
Sunshine by month
Hours of bright sunshine at Camborne
10 air frosts and under 1 days of 25°C a year
On about 10 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 9.1 miles north of Porthleven, 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 Porthleven 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 |
|---|---|---|---|
| Porthleven | 19.4°C | 4.8°C | 1,067 mm |
| Helston 2.3 mi | 19.0°C about the same | 4.3°C about the same | 1,214 mm |
| Mullion 5.2 mi | 19.2°C about the same | 5.1°C about the same | 1,036 mm |
| Goldsithney 6.1 mi | 19.3°C about the same | 5.0°C about the same | 1,097 mm |
| Reawla 6.9 mi | 19.0°C about the same | 4.5°C about the same | 1,099 mm |
| Marazion 7.4 mi | 19.3°C about the same | 5.2°C about the same | 1,094 mm |
| St Erth 7.5 mi | 19.5°C about the same | 5.1°C about the same | 1,067 mm |
Porthleven 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 | 9.7°C 49°F | 4.8°C 41°F | 7.2°C | 112 mm 4.4 in |
| February | 9.5°C 49°F | 4.3°C 40°F | 6.9°C | 90 mm 3.6 in |
| March | 10.6°C 51°F | 5.1°C 41°F | 7.8°C | 77 mm 3.0 in |
| April | 12.6°C 55°F | 6.2°C 43°F | 9.4°C | 69 mm 2.7 in |
| May | 15.2°C 59°F | 8.6°C 48°F | 11.9°C | 57 mm 2.2 in |
| June | 17.7°C 64°F | 11.1°C 52°F | 14.4°C | 66 mm 2.6 in |
| July | 19.4°C 67°F | 13.1°C 56°F | 16.2°C | 71 mm 2.8 in |
| August | 19.5°C 67°F | 13.2°C 56°F | 16.3°C | 82 mm 3.2 in |
| September | 17.8°C 64°F | 11.6°C 53°F | 14.7°C | 76 mm 3.0 in |
| October | 14.9°C 59°F | 9.6°C 49°F | 12.3°C | 108 mm 4.3 in |
| November | 12.1°C 54°F | 7.0°C 45°F | 9.5°C | 129 mm 5.1 in |
| December | 10.2°C 50°F | 5.3°C 42°F | 7.7°C | 129 mm 5.1 in |
| Year | 14.1°C | 8.3°C | 11.2°C | 1,067 mm |
Where Porthleven’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 Porthleven’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 Camborne, 9.1 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 Porthleven’s climate
How warm does Porthleven get in summer?
August is the warmest month, with average highs of 19.5°C (67°F). About under 1 days a year reach 25°C (77°F), fewer than almost every UK town.
How cold does Porthleven get in winter?
February nights average 4.3°C (40°F). The air drops below freezing on about 10 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Porthleven get?
About 1,067 mm (42 in) a year, more than 82% of UK towns. November is the wettest month (129 mm) and May the driest (57 mm).
How sunny is it?
The nearest Met Office station with a sunshine record, Camborne (9.1 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 Porthleven. 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 Porthleven →
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