Altarnun Weather Forecast, Cornwall PL15 7

Today 20 Dec South West England

A largely fine day with sunny periods. Freshening southeasterly winds developing and turning windier in the west with some spells of rain in Cornwall during the afternoon. Feeling cooler. Maximum Temperature 11C.

Tonight 20 Dec South West England

Outbreaks of heavy rain and blustery winds will spread eastwards through the evening. Drier overnight, with a mixture of clear spells and scattered showers. Winds tending to ease. Turning chilly where skies remain clear, with some fog patches forming. Minimum Temperature 4C.

Sun 21 Dec South West England

After a bright start, cloud and showery outbreaks of rain will move up from the south as the day progresses. Feeling chilly under cloudy skies. Staying breezy around the coasts. Maximum Temperature 10C.

Mon 22 Dec South West England

Often cloudy and dull through this period with some rain and drizzle possible at first. Gradually turning colder and possibly brighter with an easterly breeze developing.

Tue 23 Dec South West England

Often cloudy and dull through this period with some rain and drizzle possible at first. Gradually turning colder and possibly brighter with an easterly breeze developing.

Wed 24 Dec South West England

Often cloudy and dull through this period with some rain and drizzle possible at first. Gradually turning colder and possibly brighter with an easterly breeze developing.

Thu 25 Dec South West England

Continued mostly settled conditions expected, as high pressure builds to the north of the UK. This will bring a strengthening easterly then northeasterly wind over the period, with wind-chill making it feel colder. Whilst there will be a fair amount of dry weather, a few showers will still be possible, particularly across eastern and southern parts which may be wintry in places, more especially over high ground. High pressure will likely dominate the weather in the run up to the New Year, slowly drifting to the west. This will maintain largely settled conditions, although with an increasing chance of showery conditions later in the period. Temperatures will be below average much of the time, with frost likely where clear skies and light winds prevail.

Fri 26 Dec South West England

Continued mostly settled conditions expected, as high pressure builds to the north of the UK. This will bring a strengthening easterly then northeasterly wind over the period, with wind-chill making it feel colder. Whilst there will be a fair amount of dry weather, a few showers will still be possible, particularly across eastern and southern parts which may be wintry in places, more especially over high ground. High pressure will likely dominate the weather in the run up to the New Year, slowly drifting to the west. This will maintain largely settled conditions, although with an increasing chance of showery conditions later in the period. Temperatures will be below average much of the time, with frost likely where clear skies and light winds prevail.

Altarnun Weather Forecast

Today 20 Dec South West England

Tonight 20 Dec South West England

Sun 21 Dec South West England

Mon 22 Dec South West England

Tue 23 Dec South West England

Wed 24 Dec South West England

Thu 25 Dec South West England

Fri 26 Dec South West England

Temperature Forecast Met Office

Temperature Real-Time

Predannack (Cornwall) Radar

National Satellite

National Synoptic

Altarnun Temperature Statistics

December Temperature

Cardinham (15km)

Lowest 9 January, 2025

Average 2025

Highest 11 July, 2025

Lowest 21 November, 2025

Average November

Highest 6 November, 2025

Lowest 3 December, 2025

Average December

Highest 7 December, 2025

Climate (2020–Present)

Cardinham (15km)

Average Low 2020–2025

Average 2020–2025

Average High 2020–2025