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Brecon Beacons Forecast

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.

Sunday's Forecast

Moderate breeze, locally gusty
Sunshine and showers
Chilly

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Click here to download the latest PDF Last Updated Sat 16th May 26 at 4:04PM Last Updated Sat 16th May 26 at 4:04PM
View our low-graphics version Last Updated Sat 16th May 26 at 4:04PM Last Updated Sat 16th May 26 at 4:04PM

Viewing Forecast For

Brecon Beacons
Sunday 17th May 2026
Last updated Sat 16th May 26 at 4:04PM

Summary for all mountain areas

Scattered showers for most through morning, early low cloud (lowest west) rises to and above many summits for several hours. Showers become frequent and heavy afternoon, risk of isolated lightning and hail; showers most of the day in Scotland. Breezy in exposure, strong gusts near showers, and quite chilly.

Headline for Brecon Beacons

Cloud lifts above tops; some showers, frequent and heavy later

How windy? (On the summits)

Westerly 15-25mph through morning and into afternoon, some lower speeds possible. Then trending southwesterly and a quick rise in speed, sustained at least 25mph, up to 35mph with stronger gusts around showers.

Effect of the wind on you?

Fairly small, then becoming more blustery through afternoon, affecting comfortable walking in exposure, considerable buffeting from strongest gusts late in the day.

How Wet?

Showers develop

A little rain toward west coast early morning, odd showers then develop inland during morning. Heavier showers form middle of day onward, passing eastward in local bands, risk hail & thunder. Tending to clear into evening.

Cloud on the hills?

Patches in morning and in showers

Patchy cloud around west and southern hills in the morning. Mostly lifting to tops or above, briefly lowering with ragged patches around showers. Later, as showers become more frequent, cloud banks will more often return to high terrain.

Chance of cloud free summits?

50% rising to 80%

Sunshine and air clarity?

Largely cloudy with occasional sun, then becoming sunnier near to coast later afternoon onward. Visibility very good, but reduced in showers.

How Cold? (at 750m)

4 or 5C, most areas seeing little change but may reach up to 6C east Wales. Feeling sub-zero as wind increases, as cold as -5C.

Freezing Level

Above the summits.

Viewing Forecast For

Brecon Beacons
Monday 18th May 2026
Last updated Sat 16th May 26 at 4:04PM

How windy? (On the summits)

South-southwesterly 15-20mph, but likely stronger up to dawn. Increasing afternoon to 30mph, 40mph+ overnight.

Effect of the wind on you?

Fairly small part of day, but breezy on tops, becoming increasingly blustery, affecting comfortable walking, worsening later.

How Wet?

Local showers, rain likely later in day

Patchy rain and odd showery bursts possible in morning, likely to fade or clear away eastwards middle of day. Odd spots as high cloud thickens, then from late afternoon steadier rain develops quickly from southwest.

Cloud on the hills?

Lifting and clearing; lowering later

Varied cloud banks around hills in morning, particularly south and west areas. Lifting higher, clearing tops and increasingly breaking up into middle of day. However, later in rain, lowering back over hills.

Chance of cloud free summits?

40% rising to 80%; lowering later.

Sunshine and air clarity?

Variable cloud, few glimpses of sun, high cloud tends to build to cover the sky afternoon, increasingly overcast. Visibility very good, reducing rain.

How Cold? (at 750m)

3C rising to 6C. If exposed to increasing wind later, feeling nearer -5C, or colder toward dusk.

Freezing Level

Above the summits.

Viewing Forecast For

Brecon Beacons
Tuesday 19th May 2026
Last updated Sat 16th May 26 at 4:04PM

How windy? (On the summits)

Southerly 35-50mph, shifting southwesterly and easing, 25-35mph for a few hours, restrengthening to 40mph with time.

Effect of the wind on you?

Walking often at least strenuous on high summits with wind chill. Effects may ease for a few hours after morning.

How Wet?

Often raining, sometimes heavy

Persistent rain from before dawn lingers into the morning. Rain eases but remains frequent, most frequent on south and western slopes with heavy moments; risk of isolated hail and thunder. Wet underfoot and slippery rock surfaces.

Cloud on the hills?

Fairly extensive

Extensive to low slopes at dawn. Through morning, tending to lift, some breaks forming towards east Wales up to 700m on north slopes. West and southern slopes remain in cloud, at times to low slopes; any breaks above 600m rare and brief.

Chance of cloud free summits?

20%

Sunshine and air clarity?

Glimpses of sun in the morning, then later in the day too, otherwise largely cloudy. Visibility often poor due to rain and haze, locally better.

How Cold? (at 750m)

7 to 9C. Feeling like -5 to -8C in direct wind.

Freezing Level

Above the summits.

Planning Outlook

A mixed but milder outlook. Showery bursts of rain Monday, passing eastwards; by later Monday, strengthening southerly winds and rain moving into Wales from the southwest. Damp south-southwesterlies then prevail for a few days as mid-week approaches with regular showers, most on western hills where drizzly rain may persist between showers. Expect increasingly wet conditions underfoot, slippery rock surfaces. Also, a risk of isolated hail and lightening in the showers. Indications of high pressure building over the continent later in the week, brining milder and drier conditions to England and Wales. However, some drizzle and low cloud may continue to affect western hills, with periods of rain and wind continuing to affect Scotland. This trend may continue into the weekend, though detail currently uncertain.