Mountain weather
Bannau Brycheiniog / Brecon Beacons Mountain weather forecast table
Confidence
Generally high confidence though moderate for clearance of rain today, and low confidence for forecast detail from Sunday.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
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.
Heavy Persistent Rain
Heavy and persistent rain can lead to drenched clothing and footwear with waterproofs often becoming soaked through, especially if accompanied by strong winds. This can lead to significant loss of body heat and an increased likelihood of hypothermia. Terrain may turn increasingly boggy underfoot while streams can flood and become impassable. There may also be a risk of flooding in valleys or glens. If there is snow cover, a heightened avalanche hazard is possible and avalanche reports should be consulted where available.
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.
Thunderstorms
Lightning is a significant mountain hazard which can result in serious injury or death. Mountain terrain often leaves one highly exposed to lightning strikes. Hail may give unpleasant conditions with torrential rain and localised flash flooding also possible, mainly in Summer months.
Mountain weather forecast
Often cloudy, sometimes murky, with outbreaks of rain and drizzle.
| 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|
Weather (at 600m) |
|
|
|
|
|
|
Chance of precipitation (at 600m) |
80% | 80% | 60% | 50% | 30% | 30% |
Wind direction and speed (mph)
Altitude above mean sea level
| 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|
| 600m |
W
16
|
SW
17
|
W
17
|
SW
17
|
SW
16
|
SW
14
|
| 300m |
W
10
|
SW
12
|
W
12
|
SW
12
|
SW
10
|
SW
9
|
| Valley |
W
9
|
W
11
|
W
11
|
W
10
|
W
9
|
SW
7
|
Wind gust (mph)
Altitude above mean sea level
| 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|
| 600m | 21 | 24 | 24 | 25 | 23 | 20 |
| 300m | 21 | 23 | 23 | 23 | 21 | 18 |
| Valley | 20 | 23 | 23 | 22 | 19 | 17 |
Altitude above mean sea level
| 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|
| 600m |
6°
|
6°
|
6°
|
7°
|
6°
|
6°
|
| 300m |
8°
|
8°
|
9°
|
9°
|
9°
|
8°
|
| Valley |
8°
|
9°
|
9°
|
10°
|
9°
|
8°
|
| Freezing Level |
2,400m
|
2,300m
|
2,100m
|
1,900m
|
1,800m
|
1,600m
|
Altitude above mean sea level
| 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|
| 600m |
2°
|
2°
|
2°
|
2°
|
2°
|
2°
|
| 300m |
5°
|
5°
|
6°
|
6°
|
6°
|
5°
|
| Valley |
6°
|
6°
|
6°
|
7°
|
7°
|
6°
|
Additional weather information
Meteorologist's view
Extensive rain and drizzle will lead to slippery paths and channels of water from runoff. Rainfall likely to lead to waterproofs becoming soaked.
Weather
Outbreaks of rain and drizzle will continue through Friday, although steadily easing and pulling away to the north during the afternoon, allowing some improvement in the far south of the park by the end of the day, however moderate confidence to the clearance of the rain. Remaining cloudy even if rain and drizzle eases later during the afternoon. Murky conditions likely in persistent spells of rain, with low cloud across upslopes and peaks and some misty conditions possible.
Chance of cloud-free hill tops
20% for most of the day, improving to 60% by the evening, although confidence is low around timings of a clearance.
Low cloud and visibility
400m for much of the day, improving to rise above highest summits by the evening, with southern parts of the park likely to see the improvements first. Visibility moderate, poor or very poor in rain and drizzle.
Recent rainfall
Location: Neuadd (Near Pontsticill)
Altitude: 353m
| Last 24 hours | Last 48 hours | Last 72 hours |
|---|---|---|
| 12mm | 20.6mm | 32.2mm |
Measurement date:
Rainfall data provided by Natural Resources Wales. The Met Office is not responsible for content provided by third parties and may remove this data without warning.
Mountain weather information
Weather
A much drier day on offer with some mist and fog possible to start. This clearing quickly as the sun rises leaving a fine day with plenty of sunshine and light winds. A very low risk of showers during the afternoon.
Chance of cloud-free hill tops
80%
Maximum wind speed expected
South-westerly winds, becoming south-easterly, 15-20 mph , gusting 20-25 mph.
Temperature
- At 600m Plus 3 Celsius, rising to plus 8 Celsius.
- Valley Plus 5 Celsius, rising to plus 13 Celsius.
- Freezing level Above summits.
Low cloud and visibility
Some low cloud possible across upslopes to start with mist and fog patches where visibility will be poor. However, this dissipating quickly during the morning leaving little cloud and generally good to excellent visibility across scenic outlooks. A low risk of showers in the afternoon may temporarily reduce visibility and allow for cloudier conditions, though bases expected to remain above the highest peaks.
Mountain weather information
Sun 5 May
Sunrise:
Sunset:
Low confidence in forecast detail though generally staying unsettled with variable cloud and the potential for heavy showers and thunderstorms. Warm in any sunshine and light winds. Freezing levels above summits.
Mon 6 May
Sunrise:
Sunset:
Low confidence in forecast detail. Cloudy with the risk of spells of rain or showers with the risk of heavy showers and thunderstorms. Light winds. Freezing levels above summits.
Tue 7 May
Sunrise:
Sunset:
A drier day with a mix of sunshine and showers though confidence remains low at this stage. Feeling fairly warm once again and winds staying light. Freezing levels above summits.
Updated at:
Summit specific forecast
Mountain summit forecast map
Loading map…
Key
Mountain summits
Other points of interest
Cluster of multiple stations
The Bannau Brycheiniog / Brecon Beacons is a mountain range in South Wales comprising six main peaks, with the highest peak, Pen y Fan, standing at 886 metres.