Brecon Beacons

Includes all higher summits in the southern half of Wales: the Bannau Brycheiniog / Brecon Beacons National Park, southern Cambrian Mountains and highest Preseli hills.

Wednesday's Forecast

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Click here to download the latest PDF Last Updated Tue 5th Dec 23 at 4:28PM
View our detailed version Last Updated Tue 5th Dec 23 at 4:28PM

Viewing Forecast For

Brecon Beacons
Wednesday 6th December 2023
Last updated Tue 5th Dec 23 at 4:28PM

Summary for all mountain areas

After a hard frost, mostly dry and bright, but feeling increasingly bitterly cold as southeasterly winds strengthen and cloud thicken through the day ahead of a front, which will bring and increasing risk of upland snowfall, in across western mountains toward evening, and then spreading to all parts overnight.

Headline for Brecon Beacons

Early sun, then overcast. Bitter chill as winds strengthen. Rain/snow tops later.

How windy? (On the summits)

Southeasterly, strengthening from southwest from around 30-35mph after dawn to 40 to locally 50mph afternoon.

Effect of the wind on you?

Walking increasingly difficult, in places on lower slopes, and feeling bitterly cold as wind chill becomes significant.

How Wet?

Dry until late afternoon, then periods of rain, temporarily snow.

Dry for much of daylight, but fronts will bring persistent rain, although particularly mid Wales, initially snow., from mid to late afternoon. The change to rain will tend to occur fairly abruptly into the evening.

Cloud on the hills?

Persistent fog from most lower slopes up

Summits likely to start cloud free in the morning. Will deteriorate in afternoon with cloud base lowering extensively to 300m or lower as rain/snow arrives, although breaks above 450 Cambrian mountains.

Chance of cloud free summits?

70% lowering later in afternoon to 10%

Sunshine and air clarity?

Early sun, but soon overcast as cloud thickens. Appalling or near zero visibility in the upland snow that arrives late in the afternoon.

How Cold? (at 750m)

0 or -1C (only a degree or so warmer in valleys) post dawn; rising to 1C from southwest. Will feel as cold as minus 15C directly in the wind.

Freezing Level

450 to 700m; a transition to above the summits will extend slowly from southwest.

Viewing Forecast For

Brecon Beacons
Thursday 7th December 2023
Last updated Tue 5th Dec 23 at 4:28PM

How windy? (On the summits)

Very turbulent conditions developing. Southeasterly, later southerly, winds; lifting through day to 50 to 70mph.

Effect of the wind on you?

Be prepared for increasingly very difficult conditions, as turbulent and very powerful winds accelerate over the mountains.

How Wet?

Frequent rain, heavy at times.

Frequent spells of rain and drizzle through the day. May become heavy or intense later in the day as an active front moves in, perhaps with local thunder.

Cloud on the hills?

Very extensive

Hills widely shrouded in fog all day from lowest slopes upwards.

Chance of cloud free summits?

Less than 10%

Sunshine and air clarity?

Overcast. Poor or very poor visibilities.

How Cold? (at 750m)

4C, Feeling closer to -14C in exposure to the wind.

Freezing Level

Above the summits, but ground from mid slopes up, still partially frozen, with slow-continued thaw.

Viewing Forecast For

Brecon Beacons
Friday 8th December 2023
Last updated Tue 5th Dec 23 at 4:28PM

How windy? (On the summits)

Southerly 45 to 65mph at first, but as low tracks in, winds will veer southwesterly and ease 25 to 40mph, maybe less.

Effect of the wind on you?

Be prepared for difficult conditions with significant wind chill and buffeting. Slowly moderate into the afternoon.

How Wet?

Frequent, at times heavy, rainfall.

Low pressure will drive frequent, and at times heavy, rainfall into the area through the day. Setting in at times in the west.

Cloud on the hills?

Extensive

Extensive hill fog through the day, and at times forming from lower slopes upwards.

Chance of cloud free summits?

20%

Sunshine and air clarity?

Little if any sun. Visibility often poor due to rain.

How Cold? (at 750m)

Around 4C, but feeling more like -10C or below in direct exposure to the strongest winds.

Freezing Level

Above the summits, with upper level terrain continuing to thaw out. windy

Planning Outlook

Unsettled conditions will prevail over the next week to 10 days, with periods of upland gales or severe gales with precipitation frequent, mostly rain, although intermittently snow Scottish Highlands, more rarely elsewhere. Driest conditions (relative to the average) will likely be in the northwest Highlands, given the often backed flow, as the low pressure areas track in.