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
#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

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.
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.
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.
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.
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.
Add your own note from Cardiff's card on the map.
Cardiff climate normals — December
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)
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.
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 YearCrowdedAn 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 ↗
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?
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.