Wales has an oceanic climate with Atlantic storms and weather patterns sweeping across it through most of the year. It is humid—in fact, the wettest part of the United Kingdom—with relatively mild temperatures ranging from the low 40s in the winter to the mid-60s through the late spring and summer. Though the temperature rarely falls below freezing, during the day, Wales is also windy. That, combined with damp and cloudy conditions, can make otherwise moderate temperatures feel bitterly cold. Nights, throughout the country, can be 20 degrees Fahrenheit colder than daytime. Fog is also common in Wales. It rolls in along the coast at any time of year, but it is equally likely to settle—as low hanging clouds—on the mountain peaks. This can make mountain hikes more challenging than the mountains’ sizes might lead inexperienced hillwalkers to believe.
Fast Climate Facts
- Hottest Month: July (70 F / 21 C)
- Coldest Month: February (35 F / 1.6 C)
- Wettest Month: October (5 inches)
Coastal Weather in Wales
Wales is surrounded, on three sides, by water: the Bristol Channel to the South, the Irish Sea to the west and north. That tends to moderate coastal weather. Cardiff, on the Bristol Channel, is probably the warmest city in Wales with August temperatures rising as high as 72 F. The coasts are slightly dryer and are likely to have more hours of sunshine. But this is just a matter of degree. During the summer months, when the days are longest, an average of only six hours of sunlight a day is typical.
Although Wales has beautiful beaches, you really have to be hardy to swim. Even in August, water temperature in the Bristol Channel, the warmest body of water around Wales, reaches only about 61 F.
Inland Weather in Wales
The higher you get in Wales, the colder and wetter it gets. And as you move away from the coasts, Wales is quilted with river valleys separated by increasingly higher hills. The Brecon Beacons in central Wales, are softly rolling but enormous, windswept hills where winter temperatures below freezing and snowfalls are not uncommon. Further north, in the inland mountains of Snowdonia National Park, heavy precipitation can be extreme. One mountain peak, Crib Goch, may be the wettest place in the entire country with an astonishing 176 inches of rainfall annually. And on the highest peaks, it snows a great deal. Mount Snowdon, at 3,560 feet and the highest U.K. mountain south of Scotland, can experience snowfall from October to May.
Snowfall at lower altitudes is rare, with an average of only 10 days a year with snow lying on the ground in the south and west Wales. On the other hand, the mountains of Snowdonia average 30 days a year with snowfall lying on the ground.
Seasons in Wales
For all practical purposes, Wales really has only two seasons: autumn and winter when it gradually gets colder, grayer and wetter, and spring and summer when temperatures can rise into the 70s along the coasts and when (particularly April through June) it can be a bit dryer.
Autumn and Winter in Wales
In September, temperatures linger in the 60s but fall away rapidly through October and November into the high 40s. January and February are the coldest months with temperatures hovering around freezing or slightly above in higher areas and in the high 40s along the coast. Temperatures at night are usually 10 to as much as 15 degrees Fahrenheit colder.
October through January are the wettest months. Rain tends to fall in short, sharp and very heavy showers. November is particularly squally with rain accompanied by gusty winds.
What to pack:
Don’t bother bringing an umbrella or hats with brims. The wind will relieve you of your hat and turn your umbrella inside out in no time. Instead, bring a sturdy waterproof jacket with a waterproof hood and knitted caps to wear under it. If you are planning to spend much time out of doors, invest in a foldaway poncho with a hood (big enough to cover your backpack and to double as a groundsheet). Warm sweaters or fleeces are a must to layer over shirts or turtle necks. Extra, dry socks, and waterproof walking shoes are necessities too. And don’t overlook warm, knitted, or flannel sleepwear. Even four-star accommodations can be drafty and cold in Wales.
Spring and Summer in Wales
March is unpredictable. Some years, the weather begins to warm up while at other times there’s not much to distinguish March from February. In April and May, the highest temperatures are in the mid-50s, rising to the mid-60s for June, July, and August. On the south coast, along the Bristol Channel, temperatures are warmer—reaching the mid-70s in July and August.
In terms of rain, April through July are the driest months with average rainfall of less than four inches for those months in central Wales. In south coastal Wales, rainfall from April through June is slightly less, averaging about 2.8 inches per month.
What to pack:
A lightweight waterproof jacket with a thin fleece shirt or two to layer under it if the weather changes is sensible. So are waterproof shoes. If you are planning to be on the coast, where it’s usually a bit warmer, you can pack some shorts and open tops for catching the sun when it shows its face. But don’t pack too many summery things. It’s never really summery in Wales.
If you’re keen to swim, unless you are accustomed to really cold Atlantic waters, bring a wet suit. Even in the warmest months of summer, on the warmer south coast, water temperature rarely rises above 61 degrees.