Mountain weather

Mountain weather

Bannau Brycheiniog / Brecon Beacons

Confidence

High confidence overall, however lower confidence in the location and detail of showers, particularly later in the period.

Mountain hazards

Mountain weather hazards

Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.

Strong Sunlight
Harmful UV levels from sunlight increase with altitude giving a greater risk of sunburn and eye damage, even on some overcast days. On breezy days, the cooling effect of wind on exposed skin may disguise any feeling of sunburn until it is too late. If there is snow cover, glare increases the effect of UV rays especially on the eyes. It is advisable to wear sun block, protective clothing such as a long-sleeved top and hat and have good quality eye protection.

Severe Chill Effect
Wind significantly lowers the ‘feels-like’ temperature relative to the actual temperature, with even moderate winds significantly adding to the chilling effect. Strong winds can result in a severe and debilitating wind chill many degrees below the actual temperature. This effect will be enhanced in rain or wet snow. Without protection, prolonged exposure could result in frost nip or frostbite on exposed parts of the body and/or hypothermia.
Poor Visibility
Poor visibility presents challenging route finding conditions. Visibility could be significantly less than 50 metres in all directions with few or no visual references, especially on featureless moors or plateaux. Distances become hard to judge and cliff or cornice edges can be difficult to recognise. These conditions require good navigational skills. There is a risk of white-out conditions when mist or fog is combined with extensive snow cover.

Mountain weather forecast

Showers or outbreaks of rain clearing to sunny spells later.

Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
Weather symbols Dull Light rain Cloudy Sunny intervals Sunny Clear night
Chance of
precipitation
(at 800m)
Chance of precipitation
20%
50%
50%
10%
10%
10%

Wind direction and speed

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
600m
600m NW 12mph knots
NW
12mph
NW 16mph knots
NW
16mph
N 14mph knots
N
14mph
N 10mph knots
N
10mph
N 9mph knots
N
9mph
NW 6mph knots
NW
6mph
300m
300m W 6mph knots
W
6mph
NW 9mph knots
NW
9mph
N 8mph knots
N
8mph
N 6mph knots
N
6mph
N 7mph knots
N
7mph
W 5mph knots
W
5mph
Valley
Valley W 6mph knots
W
6mph
NW 8mph knots
NW
8mph
N 8mph knots
N
8mph
N 6mph knots
N
6mph
N 6mph knots
N
6mph
W 5mph knots
W
5mph

Wind gust

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
600m
600m 16mph 21mph 18mph 14mph 12mph 9mph
300m
300m 13mph 18mph 14mph 12mph 13mph 10mph
Valley
Valley 14mph 17mph 17mph 13mph 12mph 10mph

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
600m
600m 0 degrees Celsius 2 degrees Celsius 4 degrees Celsius 6 degrees Celsius 5 degrees Celsius 2 degrees Celsius
300m
300m 5 degrees Celsius 6 degrees Celsius 9 degrees Celsius 10 degrees Celsius 9 degrees Celsius 3 degrees Celsius
Valley
Valley 6 degrees Celsius 8 degrees Celsius 10 degrees Celsius 11 degrees Celsius 10 degrees Celsius 4 degrees Celsius
Freezing Level Freezing Level
1300m
1400m
1300m
1200m
1100m
1000m

Additional weather information

Meteorologist's view

Surprisingly chilly for the time of year, especially early and late, however UV levels will remain moderate to high throughout, so sun protection is advised. Conditions will deteriorate for a time during the morning making navigation more challenging.

Weather

A cold but bright start with a frost in places. Showers or longer spells of rain then arriving through the morning from the north. These clearing by mid-afternoon, with sunny spells then developing ahead of another cold night.

Chance of cloud-free hill tops

90% reducing to 50% for a time during the morning.

Low cloud and visibility

Cloud bases mostly above summits but lowering in any heavier bursts of rain or showers to shroud summits. Very good visibility dropping to moderate or poor in any rain.

Ground conditions

No recent ground conditions report available.

Summit specific forecast