Eryri / Snowdonia National Park
Includes all summits in the the northern half of Wales from Pumlumon northwards.
Today's Forecast
Severe gale or storm, mobility very difficult
Severe conditions on the mountains, any movement very challenging, you may be blown over. 55-70mph+
Patchy rain or drizzle
Rain on and off, or generally drizzly - total amounts small, but may be persistently damp, especially where hills are shrouded in cloud.
Cold
Air temperatures near or below freezing on high tops; if exposed to brisk winds significant chill factor on high mountains. Carry suitable clothing.
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Severe gale or storm, mobility very difficult
Severe conditions on the mountains, any movement very challenging, you may be blown over. 55-70mph+
Patchy rain or drizzle
Rain on and off, or generally drizzly - total amounts small, but may be persistently damp, especially where hills are shrouded in cloud.
Cold
Air temperatures near or below freezing on high tops; if exposed to brisk winds significant chill factor on high mountains. Carry suitable clothing.
Viewing Forecast For
Eryri / Snowdonia National Park
Saturday 21st December 2024
Last updated
Fri 20th Dec 24 at
12:04PM
Summary for all mountain areas
Widespread storm force upland winds, strongest far north, around an intense low centred north of Scotland. Snow showers very frequent across W and NW Scotland; whilst further south showers, of snow only on higher tops. Overnight rain will clear Wales from the north morning and middle of day.
Headline for Eryri / Snowdonia National Park
Severe gale or storm force upland wind. Rain at first, then a few showers.
How windy? (On the summits)
Westerly 50 to on higher tops 60mph.
Effect of the wind on you?
Considerable buffeting at times on lower slopes, whilst higher up severe wind chill and mobility often difficult. You could be blown over.
How Wet?
Rain easing to showers
Overnight rain clearing from northwest morning; soon after dawn Snowdon range. A few showers will follow, increasingly of snow on highest tops - perhaps to 800m by dusk.
Cloud on the hills?
Cloud base rising from NW morning, occasionally clearing higher tops
Morning: Fog covering the mountains, in west from lower slopes; but improving from north. By midday: patches below 550m near precipitation (mainly west Wales), whilst otherwise cloud base 800m and clearing summits east Wales.
Chance of cloud free summits?
10% rising to 40% from north later morning
Sunshine and air clarity?
Bursts of sunshine developing, mainly east Wales. Visibility poor for periods in rain, before becoming very good from north middle of day onwards.
How Cold? (at 900m)
5C dropping gradually to 3C. Will feel as cold as minus 12C directly in the wind.
Freezing Level
By dusk close to highest summits.
Viewing Forecast For
Eryri / Snowdonia National Park
Sunday 22nd December 2024
Last updated
Fri 20th Dec 24 at
12:04PM
How windy? (On the summits)
Northwesterly 60mph; particularly gusty near precipitation.
Effect of the wind on you?
Arduous walking on lower slopes, whilst higher up severe wind chill and any mobility challenging, particularly near precipitation.
How Wet?
Frequent hail and snow
Snow and hail showers, sometimes one after another or the precipitation almost constant for an hour or two (giving whiteout); mostly rain valleys and lower slopes. Least precipitation mid Wales, where for periods dry.
Cloud on the hills?
Very extensive; cloud base varying
Near precipitation cloud sometimes below 400m particularly Snowdon range, but breaks to 750m, perhaps later fleeting breaks to higher tops or more widely mid Wales.
Chance of cloud free summits?
20%
Sunshine and air clarity?
Glimpses of sunshine, mainly afternoon. Very varied visibility, sometimes excellent, but appalling or perhaps near zero in snow/blowing snow.
How Cold? (at 900m)
-2C, may rise marginally through the day. Will feel as cold as minus 18C directly in the wind.
Freezing Level
650m
Viewing Forecast For
Eryri / Snowdonia National Park
Monday 23rd December 2024
Last updated
Fri 20th Dec 24 at
12:04PM
How windy? (On the summits)
Northwest backing westerly; easing from 30, perhaps 35mph at first, perhaps temporarily 25mph.
Effect of the wind on you?
Anticipate periods of considerable wind chill and arduous walking.
How Wet?
Rain spreading east
The odd snow shower morning. Rain, or possibly temporarily snow or refrozen rain above 750m, spreading east later morning or middle of day (timing uncertain).
Cloud on the hills?
Deteriorating as cloud later envelops lower slopes
Moderate confidence of cloud lifting to or above 650-900m for a few hours (highest east Wales). But anticipate deterioration as rain approaches cloud fills in from many western lower slopes up and 500m elsewhere.
Chance of cloud free summits?
20%
Sunshine and air clarity?
Little or no sunshine as cloud thickens from west. Visibility very good; later poor in rain.
How Cold? (at 900m)
-1C, perhaps 3C before dusk. Will feel as cold as minus 9C directly in the wind.
Freezing Level
750m, will probably transition to above the summits by dusk.
Planning Outlook
A change in the weather pattern from Tuesday as high pressure progressively envelops Wales and England. Here, as in S Scotland, extensively dry and much less windy. Mild - although frost in valleys some nights. Still windy Scottish Highlands, here very mild with lying snow substantially melting. Rain frequent NW Highlands, and less so W Highlands. Further east little or no rain.