Cardiff in May
In May, Cardiff averages 16°C (61°F) during the day and 9°C (48°F) at night, with around 12 days of rain (82 mm total).
ShoulderConditions are cool — bring a jacket for evenings. Plan for unsettled weather and bring rain gear.
May in Cardiff is outside the typical sweet spot for sightseeing weather. It can still be a great time to visit if you have specific reasons (festivals, off-season pricing, etc.).
How May compares to the rest of the year in Cardiff
May is in the middle of the year for warmth in Cardiff (5th of 12) and one of the driest months (10th of 12). Daytime temperature runs 2°C above the annual average (14°C). May runs 3°C warmer than April (13°C) and warms a further 3°C into June (19°C).
May sunrise & sunset in Cardiff
Times shown for Cardiff local time (Europe/London), calculated for the 15th of May. They shift by a few minutes day to day across the month.
Photography light in Cardiff — May
Golden-hour and blue-hour windows for the 15th of May, in Cardiff's local time. Use these for soft warm light (golden) or cool architectural twilight (blue).
📅 When to book — Cardiff in May
Travel writers usually only tell you when to go. Here's when to book flights and lodging for the best mix of price and availability, based on May's tier (Shoulder) and Cardiff's popularity.
May in United Kingdom — events that affect travel
Known cultural, religious, or national events that surge prices, fill hotels, or close businesses during this month. Plan around them, or build your itinerary around the ones you'd like to see.
UK has long-weekend bank holidays in early May, late May, and late August. Many independent shops and some attractions close; popular destinations (Cotswolds, Cornwall) get busy.
Plan: Sundays + Mondays surrounding bank holidays = peak domestic travel. Book accommodation 4-6 weeks out.
Crowds & pricing — May in Cardiff
Cardiff is in a shoulder season month — fewer crowds, slightly lower prices, and a calmer atmosphere than peak weeks. Most major sights stay open with normal hours, though a handful of seasonal restaurants or boat trips may run reduced schedules. Many regulars consider these months the best time to visit because you trade a small amount of weather reliability for a much more pleasant on-the-ground experience.
Why this tier: comfortable tourism weather
Sun & mosquito risk — May in Cardiff
UV is a clear-sky sea-level estimate — clouds, altitude, and reflective surfaces (snow, water) shift it ±30%. Mosquito risk is climate-derived only; for current disease advisories (dengue, malaria, zika) check the CDC or WHO travel pages before your trip.
Cardiff in other months
| Month | Avg high | Avg low | Rainfall | Rain days | Snow days |
|---|---|---|---|---|---|
| January | 8°C / 47°F | 3°C / 38°F | 111 mm | 17 | — |
| February | 9°C / 48°F | 3°C / 38°F | 102 mm | 14 | — |
| March | 10°C / 51°F | 4°C / 40°F | 97 mm | 16 | — |
| April | 13°C / 56°F | 5°C / 42°F | 61 mm | 10 | — |
| May | 16°C / 61°F | 9°C / 48°F | 82 mm | 12 | — |
| June | 19°C / 67°F | 12°C / 54°F | 67 mm | 13 | — |
| July | 21°C / 69°F | 14°C / 56°F | 80 mm | 14 | — |
| August | 20°C / 68°F | 13°C / 56°F | 105 mm | 15 | — |
| September | 18°C / 65°F | 12°C / 53°F | 87 mm | 12 | — |
| October | 15°C / 59°F | 10°C / 49°F | 134 mm | 15 | — |
| November | 11°C / 52°F | 6°C / 43°F | 114 mm | 16 | — |
| December | 9°C / 49°F | 5°C / 41°F | 139 mm | 18 | — |
Other cities with similar May weather
🌍 See the full ranked list of climate twins for Cardiff in May →
Frequently asked questions
How hot is Cardiff in May?
In May, Cardiff averages a high of 16°C (61°F) and a low of 9°C (48°F) — generally cool.
Does it rain a lot in Cardiff in May?
May can be fairly wet in Cardiff, with about 12 rainy days on average.
Is May a good time to visit Cardiff?
May is cool. It suits travelers who are comfortable with cool weather; check the month-by-month ranking to compare it against the rest of the year.
What should I pack for Cardiff in May?
Pack a warm jacket and layers, plus a compact umbrella or rain jacket. See the full May packing list for Cardiff for a complete, climate-based checklist.
Check the live 10-day forecast and sunrise/sunset.