Mountain weather
Bannau Brycheiniog / Brecon Beacons Mountain weather forecast table
Confidence
High for a mainly dry, but very windy and cold Christmas period, with severe wind chill, especially at height. Also high for the settled conditions continuing into the weekend, but turning a little less cold, with the wind also easing a little by Sunday.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
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.
Gales
Gale force winds (gusts over 50mph) make walking difficult and strenuous with a potential to be blown over by gusts. There is often a marked increase in winds through cols or on exposed ridges and summits. Distances can take longer to cover and compass bearings become harder to follow accurately.
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
Cold Christmas Eve with severe wind chill, but with plenty of fine weather
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
Weather (at 600m) |
|
|
|
|
|
|
Chance of precipitation (at 600m) |
20% | 10% | <05% | <05% | <05% | <05% |
Wind direction and speed (mph)
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 600m |
E
28
|
NE
28
|
E
28
|
E
26
|
E
25
|
NE
22
|
| 300m |
E
15
|
NE
17
|
E
16
|
NE
16
|
E
14
|
NE
13
|
| Valley |
E
15
|
E
15
|
E
14
|
E
15
|
E
12
|
NE
10
|
Wind gust (mph)
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 600m | 35 | 35 | 39 | 37 | 36 | 31 |
| 300m | 29 | 32 | 29 | 31 | 29 | 27 |
| Valley | 29 | 30 | 28 | 31 | 27 | 24 |
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 600m |
0°
|
-1°
|
-1°
|
-1°
|
-1°
|
0°
|
| 300m |
2°
|
2°
|
1°
|
1°
|
0°
|
2°
|
| Valley |
3°
|
2°
|
2°
|
2°
|
1°
|
2°
|
| Freezing Level |
500m
|
400m
|
300m
|
300m
|
200m
|
400m
|
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 600m |
-8°
|
-9°
|
-10°
|
-9°
|
-9°
|
-8°
|
| 300m |
-3°
|
-4°
|
-4°
|
-4°
|
-5°
|
-3°
|
| Valley |
-2°
|
-3°
|
-3°
|
-3°
|
-4°
|
-1°
|
Additional weather information
Meteorologist's view
Wind will be the main hazard on Christmas Eve, especially across the higher routes. These will bring difficult walking at times, with gusts around 50mph, but also a significant chill effect, leading to temperatures feeling more like minus double figures of Celsius. Warm and windproof layers, along with hat and gloves, will be essential.
Weather
A dry, but rather cloudy start. Cloud will thin and break through the day, leading to some sunshine, although a few patches will persist on eastern hills. Feeling cold, especially when exposed to the strong and gusty winds, with severe wind chill and a chance of gales across the highest tops.
Chance of cloud-free hill tops
30% becoming 80% by the afternoon, best chances in the west.
Low cloud and visibility
Extensive cloud is expected to obscure routes above 400m at first, Cloud will thin through the afternoon, however some patches could persist above 600m, mainly in the east. Outside of any cloud, visibility will be very good.
Recent rainfall
Location: Neuadd (Near Pontsticill)
Altitude: 353m
| Last 24 hours | Last 48 hours | Last 72 hours |
|---|---|---|
| 0mm | 2mm | 10.2mm |
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
Cloud will return overnight, especially across higher eastern hills, but will soon thin and clear again through the morning. A fine and dry Christmas Day follows, with some long sunny periods, but still very windy with a severe wind chill at height. Staying cold, especially in exposure.
Chance of cloud-free hill tops
40%, with best chance in the west. Becoming 90% for all by the afternoon.
Maximum wind speed expected
East 40mph gusting 50mph.
Temperature
- At 600m Minus 2 Celsius.
- Valley Zero rising to Plus 3 Celsius
- Freezing level 300m, falling to valley floors in the evening.
Low cloud and visibility
A layer of cloud likely obscuring hills above 700m during the morning, mainly in the east, but gradually breaking and clearing by the afternoon. Hills likely remaining clear through the evening. Visibility will be very good outside of morning cloud, and likely becoming excellent through the afternoon.
Mountain weather information
Fri 26 Dec
Sunrise:
Sunset:
Similar to Christmas Day, with Boxing Day seeing long sunny periods, but also strong and gusty easterly winds with a severe wind chill. Staying cold, with the freezing level rising to 400m
Sat 27 Dec
Sunrise:
Sunset:
Another windy day with sunny spells, but turning a little cloudier through the afternoon. Temperatures also recovering slightly, but still feeling cold in the strong winds. Freezing level rising above summits
Sun 28 Dec
Sunrise:
Sunset:
Winds easing Sunday, and likely cloudier than Saturday, but staying dry. Freezing level falling to 700m
Updated at:
Summit specific forecast
Mountain summit forecast map
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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.