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Eryri / Snowdonia National Park Forecast

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 near-impossible
Heavy rain
Poor visibility
Cold

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Click here to download the latest PDF Last Updated Fri 8th Dec 23 at 4:30PM Last Updated Fri 8th Dec 23 at 4:30PM
View our low-graphics version Last Updated Fri 8th Dec 23 at 4:30PM Last Updated Fri 8th Dec 23 at 4:30PM

Viewing Forecast For

Eryri / Snowdonia National Park
Saturday 9th December 2023
Last updated Fri 8th Dec 23 at 4:30PM

Summary for all mountain areas

Patchy rain and snow on higher Scottish tops push north over the Highlands. Heavy rain sets in across south & central Scotland. Heavy rain moves across England and Wales in the morning, followed by showers. Varied winds, fairly light much of Scotland, but increasing upland gales for England, severe for Wales.

Headline for Eryri / Snowdonia National Park

Increasingly severe gales. Heavy rain then showery bursts.

How windy? (On the summits)

Southerly 20 to 30mph at first, but soon turning westerly strengthening rapidly 50 to 60mph, reaching 70mph with stronger gusts into the afternoon.

Effect of the wind on you?

Soon becoming difficult with significant wind chill and buffeting. Increasingly severe conditions as day progresses.

How Wet?

Heavy rain soon clearing to showers.

Heavy rain before dawn, will soon clear after dawn to the east. Then dry for a time, but not long until heavy showers push in from the west. Risk thunder. Sleet highest tops.

Cloud on the hills?

Extensive

Cloud will shroud the hills extensively for much of daylight hours, despite a rise in bases to upper slopes as the day progresses.

Chance of cloud free summits?

20%

Sunshine and air clarity?

Mostly overcast, but some patchy sun perhaps breaking through afternoon. Visibility often poor due to rain.

How Cold? (at 900m)

6C later falling to 3C, but will feel closer to -10C in direct exposure to strongest winds.

Freezing Level

Above the summits

Viewing Forecast For

Eryri / Snowdonia National Park
Sunday 10th December 2023
Last updated Fri 8th Dec 23 at 4:30PM

How windy? (On the summits)

South to southwesterly, 35 to 50mph, risk of strengthening further to 60-70mph+, especially later in the day.

Effect of the wind on you?

Arduous or difficult walking conditions and significant wind chill over higher terrain much of the day. Risk becoming severe.

How Wet?

Heavy rain

Rain starting from before dawn, soon heavy and persistent, continuous falls lasting several hours into morning. Likely to break up into middle of day, but showery bursts follow, rain may remain frequent.

Cloud on the hills?

Extensive

Blanket low cloud across the hills, from mid or low elevations upward in west. Highest bases northeast of Ogwen valley. May start to break and rise late in the day.

Chance of cloud free summits?

10%

Sunshine and air clarity?

Overcast and dull. Visibility poor due to rain.

How Cold? (at 900m)

3C rising to 5C. Wind chill feeling like -10C on tops.

Freezing Level

Above the summits with any pockets of snow on high tops very wet and continuing to thaw.

Viewing Forecast For

Eryri / Snowdonia National Park
Monday 11th December 2023
Last updated Fri 8th Dec 23 at 4:30PM

How windy? (On the summits)

Expect westerly gales 50-60mph+ from before dawn, likely to ease into daytime to 20-30mph, perhaps less afternoon.

Effect of the wind on you?

Beware challenging conditions at least early in day, may remain blustery and chilly much of daylight, some improvement.

How Wet?

Showery rain

Overnight rain likely to clear, but showery conditions likely to continue, most frequent over west coastal hills, a mix of drizzle and some steadier rain, briefly heavy.

Cloud on the hills?

Often covering many tops

Cloud likely to shroud many higher areas all day, from mid-slopes up toward west, tending to rise with some breaks inland and northeast from Ogwen valley.

Chance of cloud free summits?

20%

Sunshine and air clarity?

Largely cloudy, glimpses of sun toward east. Visibility good out of cloud, but reduced in showers.

How Cold? (at 900m)

3C. Wind chill risk feeling as cold as -10C at first, near -5C all day if exposed to wind.

Freezing Level

Above the summits.

Planning Outlook

Areas of low pressure dominate into the weekend and early next week bringing unsettled conditions as a series of fronts circulate over Britain. Periods of heavy rain, with snow over higher mountains in Scotland as tops stay near or just below freezing point. Some freeze-thaw higher up, but mid-heights generally above freezing - very wet underfoot due to rain and snowmelt, beware flooding of streams and rivers. Most tops in England and Wales above freezing with terrain not frozen apart from local snow pockets. Generally windy, gales or severe gales at times over the tops - strongest speeds most sustained for England and Wales. Least windy in northern Scotland.