Snowdonia National Park Forecast

Also includes higher summits south to Plynlimon.

Viewing Weather Forecast for Wednesday 20th June 2018
Forecast last updated on Tuesday 19th June 2018 at 4:07pm

Today | Thursday | Friday

Summary for all mountain areas

Fronts will clear slowly south-eastwards across England and Wales, bringing rain and low cloud for several hours, then becoming brighter from the north. Scotland sees scattered showers, these becoming heavier and more widespread later, of snow on highest summits.

Headline for Snowdonia National Park

Rain on and off, fading slowly. Low cloud lifting later.

How windy? (On the summits)

West or southwesterly; up to 35 to 45mph for several hours early morning, tending to ease toward 20mph, or less afternoon. Nearer 25mph before sunset.

Effect of wind on you?

Arduous walking conditions on higher areas at least for a few hours, slowly improving into middle of day onward.

How Wet? (Precipitation and its impact)

Rain for many hours west; very little east

Rain or drizzle starting before dawn likely persist on western hills around Snowdon and the west coast until early afternoon, fading slowly later. Very little reaching east Wales.

Cloud on the hills?

Extensive, lowest west; breaking toward evening.

Widely shrouding the hills, perhaps most of the day, from lower slopes up around Cardigan Bay, and 500-600m inland. Most cloud often above 600m toward Berwyn mountains. Later in afternoon, cloud base tending to lift, and during evening some breaks forming to higher tops.

Chance of cloud free summits?

10% west; 40% east most of day. By evening: 60% west, 80% east.

Air clarity (below cloud)

Generally overcast, perhaps a little sun late in day. Visibility poor in rain, may slowly improve later; locally good east Wales.

How Cold? (at 900m)

5 to 8C; fairly humid at first, the air becoming fresher later.

Freezing Level

Above the summits.

Planning Outlook

All mountain areas of Britain from Thursday 21st June 2018

High pressure builds from the west later this week to bring plenty of fair weather over the next week to 10 days. This weekend has a risk of patchy rain and low cloud for the north-western Highlands brought in on fresh westerly winds, otherwise it will be dry with many summits clear. Rather cool in the short term, but temperatures rising into next week, and eventually it may become widely hot and humid. By the end of June this may break into thunderstorms. Check our latest planning outlook video at, updated Tuesday and Friday.

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