The climate of south-west England is classed as oceanic (Cfb) according to the Köppen climate classification. The oceanic climate is typified by frequent cloudy skies, cool winters with cool summers and precipitation all year round, with more experienced in winter. Annual rainfall is about 1,000 millimetres (39 in) and up to 2,000 millimetres (79 in) on higher ground. Exceptions include areas to the east of high ground (e.g. Exeter / parts of West Somerset that are subject to a rain shadow effect and annual rainfall is closer to 30 inches).
Summer maxima averages range from 18 °C (64 °F) in the Scillies to 22 °C (72 °F) in the east north-east of the region and winter minima averages range from 1 °C (34 °F) in the north-east of the region to 5 °C (41 °F) across the extreme south-west of Cornwall and the Scillies. Cold snaps are generally less intense or prolonged in the south west and rarely does the temperature fall below −15 °C (5 °F). Similarly, prolonged heat is fairly rare, however in recent years there have been more heatwave related conditions, albeit fairly short affairs but in July 2022 temperatures have hit 36 °C (97 °F) in Bude and other parts of the region temperatures were between 33 and 35 °C (91 and 95 °F) widely in more inland locations.
The south west is the second windiest area of the United Kingdom, the majority of winds coming from the south-west and north-West. Government organisations predict the area will experience a rise in temperature and become the hottest region in the United Kingdom.
Inland areas of low altitude experience the least amount of precipitation. They have the highest summer maxima temperatures, but winter minima are lower than those of the coast. Snowfalls are more frequent in comparison to the coast, but less so in comparison to higher ground. They experience the lowest wind speeds and the total sunshine hours are between those of the coast and the moors. This typical climate of inland areas is more noticeable the further north-east into the region.
In comparison to inland areas, the coast experiences high minimum temperatures, especially in winter, and slightly lower maximum temperatures during the summer. Rainfall is lowest at the coast and snowfall there is rarer than the rest of the region. Coastal areas are the windiest parts of the peninsula and they receive the most sunshine. The general coastal climate becomes more prevalent further south-west into the region.
The south-west has areas of moorland inland such as Bodmin Moor, Dartmoor and Exmoor. Because of their high altitude they experience lower temperatures and more precipitation than the rest of the south west (approximately twice as much rainfall as lowland areas). Both of these factors also result in the highest levels of snowfall and the lowest levels of sunshine. Exposed areas of the moors are windier than the lowlands and can be almost as windy as the coast.
Sunshine is highest on the coast as convective clouds tend to form slightly inland as the ground heats up faster. Annual amounts are around 1700/1800 hours for places like Torquay, Falmouth, Newquay and Ilfracombe, whilst inland areas such as Yeovil, Tiverton and Exeter are cloudier, prone to fog and consequently 1450/1600 hours are more typical.