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Snowdonia National Park Forecast

Snowdonia National Park

Includes all summits in the the northern half of Wales from Plynlimon northwards.

Click here to download the latest PDF Last Updated Tue 11th Aug 20 at 3:44PM Last Updated Tuesday 11th August 2020 at 3:44PM
View our low-graphics version Last Updated Tue 11th Aug 20 at 3:44PM Last Updated Tuesday 11th August 2020 at 3:44PM

Viewing Forecast For

Snowdonia National Park
Wednesday 12th August 2020
Last updated Tuesday 11th August 2020 at 3:44 PM

Summary for all mountain areas

Very warm or hot by afternoon and very high humidity - anticipate dehydration and possible sunburn. Scattered thunderstorms will drift about slowly, mainly England and Wales, bringing locally torrential rain.

Headline for Snowdonia National Park

Very warm indeed with hazy sunshine; threat thunderstorms.

How windy? (On the summits)

South or southeasterly, 10mph or less.

Effect of the wind on you?

Negligible.

How Wet?

Risk thunderstorms

Scattered thunderstorms at any time, will give locally heavy or torrential rain. The storms least likely Snowdon, Glyder and Carneddau areas.

Cloud on the hills?

Summits frequently cloud free

After dawn: very varied; some fog lower slopes and valleys whilst in other areas fog higher up, and some summits above low cloud. All or nearly all summits will clear by mid morning, although banks of fog returning to some areas in and after rain.

Chance of cloud free summits?

80%

Sunshine and air clarity?

Hazy sunshine, although cloud will come and go. Hazy, and visibility very poor in heavy rain.

How Cold? (at 900m)

17C.

Freezing Level

Above the summits.

Viewing Forecast For

Snowdonia National Park
Thursday 13th August 2020
Last updated Tuesday 11th August 2020 at 3:44 PM

How windy? (On the summits)

Northeast or easterly generally 20 to perhaps locally 30mph.

Effect of the wind on you?

Mostly fairly small.

How Wet?

Patches of rain, risk thunder

Thunderstorms may well continue to drift about, in places the giving little more than bursts of rain, whilst in other areas, particularly mid Wales, the rain heavy or torrential for a couple of hours.

Cloud on the hills?

Extensive, particularly east

Confidence low. Broadly, will improve particularly west Wales, after banks of fog from valleys up post dawn. Nevertheless, throughout day, cloud may come and go above 400m east Wales and 750m west Wales.

Chance of cloud free summits?

40%

Sunshine and air clarity?

Pockets of hazy sunshine, mainly west Wales. Continuing very hazy.

How Cold? (at 900m)

16C.

Freezing Level

Above the summits.

Viewing Forecast For

Snowdonia National Park
Friday 14th August 2020
Last updated Tuesday 11th August 2020 at 3:44 PM

How windy? (On the summits)

East or northeasterly 15 to locally 25mph - strongest winds may extend to some lower slopes.

Effect of the wind on you?

Fairly small - although sudden buffeting in gusts some lower slopes.

How Wet?

Thundery downpours

Remnants of thunderstorms will drift about slowly, bringing a mix of pockets of light rain, but also patches of heavy rain. From about midday, risk of renewed thunderstorms bringing local torrential downpours.

Cloud on the hills?

Summits clearing intermittently

Ribbons of fog from some valleys up after dawn, extensive some higher areas. Nevertheless, some summits cloud free (in places above the fog). Will vary during the day as rain comes and goes, at times cloud filling in from lower slopes up, but particularly W Wales, sometimes clearing.

Chance of cloud free summits?

30%

Sunshine and air clarity?

Occasional sunshine. Continuing hazy or very hazy; visibility very poor in heavy rain.

How Cold? (at 900m)

15C.

Freezing Level

Above the summits.

Planning Outlook

Remaining warm and particularly England and Wales humid. However, thundery rain will become mostly confined to Wales, whilst the Scottish Highlands are extensively dry. Overall extensive sunshine, although banks of very low cloud, mainly more eastern mountains, including those in east Wales. A change to wetter and gradually less warm conditions across Britain is likely early next week.