Wales Weather, climate and geography
Wales tends to be wetter than England, with slightly less sunshine. Temperatures in the coastal areas, however, can be very warm in summer ranging from 15°C (59°F) to rare highs of around 25°C (77°F). Conditions in upland areas such as the peaks of Snowdonia or the Brecon Beacons can be changeable at all times of the year. Be prepared for sudden downpours in summer as well as winter.
The summer months of June to August are the hottest, though they are also the busiest as they coincide with the school holidays. Beaches are heaving with families, hotels are rammed and attractions are a frenzy of queues. For those able to travel outside of the holidays, May and September will offer lovely warm days without the hectic crowds.
Similar to the rest of the UK, dress according to season. Waterproofs are advised for both the winter and summer; take a look at the weather forecast before embarking on outdoorsy activities. Take strong hiking boots if doing any trekking through mountainous areas, and warm clothes such as fleeces and thermals are likely to be required for upland areas. During summer if the weather is good, lightweight fabrics are fine, although it is always sensible to take some heavier layers, just in case the weather turns.