Cardiff weather in December

December in Cardiff: cold, rainy, with clean air — a fair time to visit.

Updated September 2026 · climate normals from ERA5 reanalysis

Cardiff🇬🇧 United Kingdom · British Isles · City51
  1. 54Jan
  2. 59Feb
  3. 65Mar
  4. 76Apr
  5. 83May
  6. 88Jun
  7. 91Jul
  8. 89Aug
  9. 79Sep
  10. 68Oct
  11. 58Nov
  12. 51Dec

#12 of 12 months in Cardiff · #1141 of 1413 destinations to visit in December · comfort 51/100 (tier D)

Days
10°C
Nights
5°C
Wet days
15
Sun
3.1 h
Humidity
88%
Daylight
8 h
Cardiff, United Kingdom
Photo: Vladislav Lolenko · Pexels

Traveller notes on Cardiff in December

Notes from nearby Bournemouth (124 km away)

Cardiff doesn't have its own notes for December yet — these are about Bournemouth, close enough to share the season.

Bournemouth-forum threads on local weather describe December as one of the wetter months of the year here, rain a regular feature across a real share of days, temperatures rarely climbing much past the high 40s Fahrenheit even at midday. Posters note it can dip to freezing on a cold snap, though such stretches seldom last more than a day or two before moderating again. Snow is called genuinely uncommon this close to the coast, with most winters bringing only light flurries that melt quickly rather than settling into anything photogenic. Wind off the Channel is a near-constant feature regardless of temperature, worth a proper windproof layer even on a day that isn't especially cold. The pier and seafront promenade are still called worth a walk on a clear day, bracing rather than pleasant, but a genuine local tradition regardless. The record: 10.6C days feeling like 7C, 3.9C nights, 84mm across 12.8 days, a 10.3C sea, 86 percent humidity and just 3.2 hours of sun.
BournemouthPierDecemberRegular · December · 1 month ago · about Bournemouth · Read more on Tripadvisor ↗

Other months in Cardiff

Forum posters describe February across Wales as starting cold, dark and potentially stormy, typically settling somewhat in the second half of the month, with rain and frost likely and snow a real possibility in places. Posters specifically note that Cardiff's sheltered position on the Bristol Channel spares it the extremes seen elsewhere in Wales, making it one of the UK's milder cities where snow stays rare even so - winters here run wet and raw rather than bitterly cold. Posters consistently recommend a hat over an umbrella given how often wind drives the rain sideways, alongside waterproof shoes and thick socks. Posters generally rate February as damp, blustery but comparatively mild for Cardiff specifically relative to the rest of Wales, workable with solid waterproof gear.
Tripadvisor community · February · 1 month ago · Read more on Tripadvisor ↗
Forum posters describe Cardiff's sheltered position on the Bristol Channel as giving it one of the milder climates in the UK, without the temperature extremes some other parts of Britain see, and note that snow in the city itself is rare even in January - it's much more likely up in the higher elevations of the Brecon Beacons. Posters are consistent that mild and wet describes a typical south Wales January far better than cold and snowy, with most of the region's heaviest rain actually concentrated in the October-through-January stretch. Posters flag the short winter days as a real factor, with darkness for around 15 hours. Posters generally rate Cardiff as a fine January destination for its castle, museums and Cardiff Bay, while noting that bus service to surrounding holiday areas runs more limited this time of year than in peak season.
Tripadvisor community · January · 1 month ago · Read more on Tripadvisor ↗
Cardiff forum regulars call August the hottest stretch of the year locally but rarely an extreme one: “on occasion can be hot, but rarely uncomfortably so,” with Cardiff singled out as one of the mildest cities in the UK, generally spared the heavier rainfall that hits Wales's upland areas. When rain does come it's “more likely to be light rain or drizzle” than a proper downpour, so a light rain jacket covers most days rather than full waterproofs, though regulars still pack wellies just in case. The one genuine crowd risk: on a rare hot August weekend, beaches fill up fast and parking gets difficult. Our record: 20°C days, 14.3°C nights, 12.2 rain days and a 19.1°C sea — mild rather than hot, matching the “rarely uncomfortably warm” read closely.
Tripadvisor community · August · 1 month ago · Read more on Tripadvisor ↗
The forum's honest summary of a Cardiff July is that it could be very hot, could be chilly, or could rain without stopping — Welsh weather being "entirely unpredictable" — but they rate July as the more reliable month than August if the dates are yours to choose, particularly for hiking. What July reliably is not is oppressive: averages sit near 20°C, which regulars count as an advantage over Mediterranean destinations in high summer. Rain lands on around a dozen days across the month, so the standing packing advice is light summer clothes plus a thin sweater and a light waterproof.
Tripadvisor community · July · 1 month ago · Read more on Tripadvisor ↗

Add your own note from Cardiff's card on the map.

Cardiff climate normals — December

Daytime high10°C / 50°F🧥 cold
Nighttime low5°C / 42°F
Feels like (high)6°C / 43°F
Sea temperature8°C / 46°F🥶 cold sea
Rainfall121 mm / 4.8 in🌧 rainy
Rainy days15 days
Humidity88%💦 very humid
Dew point6°C / 43°F
Sunshine3.1 h/day
Daylight7.9 h
Wind26 km/h / 16 mph
Snowfall1.5 cm / 0.6 in
Air quality (US AQI)34🍃 good

Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.

Crowds in Cardiff in December

How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.

Peak crowdsCardiff Winter Wonderland, Christmas holidays in United Kingdom, school holidays in 6 of the markets that fill it(estimated)

JFMAMJJASOND

Peak crowdsBusyShoulder seasonQuiet

Best months for Cardiff's weather

Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).

Toughest weatherCardiff's weather peaks June–August, best around July.

JFMAMJJASOND

Best weatherFair weatherToughest weather

What's on in Cardiff in December

Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.

  • Opening

    Cardiff Winter Wonderland

    10 Nov – 5 Jan · usuallyChristmas & New YearCrowded

    An open-air rink, a big wheel and a beer hall take over the civic centre lawns from mid-November until after New Year, alongside the Christmas market in the pedestrian streets. Source ↗

What's on around the world in December →

Nearby, and something's on

Within 300 km of Cardiff — a day trip or a short hop — with something on this month. Never part of the comfort score.

Where is Cardiff?

Loading map…

Cardiff in December — FAQ

Is December a good time to visit Cardiff?
December in Cardiff: cold, rainy, with clean air — a fair time to visit. It ranks #12 of 12 months for Cardiff on SeasonMap's comfort score (51/100).
What is the weather like in Cardiff in December?
In December, Cardiff averages a daily high of 9.8°C and a low of 5.3°C, with about 120.7 mm of rain over roughly 15.3 rainy days.
What is the air quality in Cardiff in December?
Cardiff has a mean US Air Quality Index of about 34 in December.
Does it snow in Cardiff in December?
Cardiff sees roughly 1.5 cm of snowfall in December.

Within 300 km: Bristol's Bristol Christmas Market on 6 Nov – 23 Dec, and Bath's Bath Christmas Market on 26 Nov – 13 Dec.