Wales has a mild, wet maritime climate. It rains in every season, the west more than the east, and the weather on the mountains can be very different from the coast. Summers are rarely hot and winters rarely very cold, though Yr Wyddfa and the Beacons get snow.
May to September is the main season, with long days, the coast path at its best and boats to the islands running. The puffins on Skomer are there from about April to July. July and August are the busiest months, especially in Pembrokeshire and Snowdonia.
Spring and early autumn are often the best compromise: fewer people, lower prices and plenty of settled spells. Autumn brings seal pups to the beaches of Pembrokeshire and Ramsey Island.
Events worth timing a visit around: - the Hay Festival of literature at Hay-on-Wye, in late May; - the Royal Welsh Show at Builth Wells in July; - the National Eisteddfod, which moves to a different town each year, in early August; - Six Nations rugby matches in Cardiff in February and March, when the city is at its liveliest.