Cardiff weather by month

The best time to visit Cardiff is June to August — 91/100 in July, 22°C and 12 rainy days. The best season is summer, June to August (89/100 on average).

The worst month is December at 51/100 — cold, rainy, clean air. See December →

Updated September 2026 · climate normals from ERA5 reanalysis

Planning the wider trip? Best time to visit United Kingdom →

Cardiff🇬🇧 United Kingdom · British Isles · City91
  1. 54Jan
  2. 59Feb
  3. 65Mar
  4. 76Apr
  5. 83May
  6. 88Jun
  7. 91Jul
  8. 89Aug
  9. 79Sep
  10. 68Oct
  11. 58Nov
  12. 51Dec

Best season: June to August (89/100 on average) · worst December (51/100)

Days
22°C
Nights
14°C
Wet days
12
Sun
10.9 h
Humidity
77%
Daylight
16 h
Cardiff, United Kingdom
Photo: Vladislav Lolenko · Pexels

Cardiff, month by month

Comfort score out of 100 for the kind of trip Cardiff is best for, the average high, rainy days and hours of sun a day from the climate normals, and how busy it tends to be.

MonthScoreTierHighRainSunCrowdsOn
Jan54D8°C14 d4 hPeak1
Feb59D9°C13 d5 hPeak1
Mar65C11°C14 d7 hBusy1
Apr76B14°C11 d9 hBusy1
May83A17°C12 d11 hBusy—
Jun88A20°C11 d11 hBusy1
Jul91S22°C12 d11 hPeak1
Aug89A21°C12 d10 hBusy—
Sep79B19°C13 d8 hShoulder—
Oct68C15°C15 d6 hPeak1
Nov58D11°C15 d4 hPeak2
Dec51D10°C15 d3 hPeak1

What's on in Cardiff through the year

Festivals, natural spectacles, holidays and the seasons to watch out for — curated and sourced. The month pages carry the detail.

February
  • Six Nations match days1 Feb – 20 Mar (usually)Festival
April
  • Children's Literature Festival18–30 Apr (usually)Festival
June
  • Tafwyl15–25 Jun (usually)Festival
July
  • Cardiff Food and Drink Festival1–12 Jul (usually)Festival
October
  • Cardiff Half Marathon1–12 Oct (usually)Festival
November
  • Autumn internationals1–30 Nov (usually)Festival
  • Cardiff Winter Wonderland10 Nov – 5 Jan (usually)Opening

Everything on in Cardiff through the year →

Crowds in Cardiff in July

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 Food and Drink Festival, Summer holidays in United Kingdom, school holidays in 6 of the markets that fill it(estimated)

JFMAMJJASOND

Peak crowdsBusyShoulder seasonQuiet

Good to know before you go to Cardiff

Real experiences from travellers' own write-ups, quoted with a link to the original.

practical

We visited Cardiff Castle midweek during term time specifically to dodge the weekend and school-holiday crowds, and the quieter pace let us actually take in how strange the layering of history is here, a Roman fort becoming a Norman keep becoming a Victorian Gothic fantasy on the exact same site. We downloaded the free castle app for a self-guided audio tour rather than paying for the official guided option, and it covered everything we wanted to know. Climbing the keep first, while our legs were still fresh, gave us the best rooftop views before we tackled the Bute Apartments, each room decorated in its own elaborate Victorian theme. We budgeted a full four hours and used every minute of it.
Rhys E. · Read the original ↗

Traveller notes on Cardiff

What people who have been say about the place — the year-round notes first, then month by month.

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 ↗
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 ↗
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 ↗
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 ↗

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