Bannau Brycheiniog / Brecon Beacons Mountain weather forecast table
Confidence
High for Wednesday, and for a generally unsettled rest of the week. Some uncertainty in the position of heavy rain and strength of winds on Thursday, and for position of rain bands over the weekend.
This evening forecast
A fine dry evening and start to the night with clear skies. Light to moderate westerly winds. Freezing level 800-900m, occasionally above the summits.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Poor Visibility
Heavy Persistent Rain
Gales
Severe Chill Effect
Mountain weather forecast
Rain soon turning heavy and persistent. Strong summit winds.
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
Weather (at 600m) |
|
|
|
|
|
|
|
|
Chance of precipitation (at 600m) |
00% | 00% | <05% | 80% | >95% | >95% | >95% | 70% |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 600m |
S
11
|
S
15
|
S
23
|
S
31
|
S
31
|
S
30
|
S
30
|
SW
29
|
| 300m |
SW
7
|
S
7
|
S
12
|
S
19
|
S
19
|
S
20
|
S
19
|
SW
18
|
| Valley |
S
4
|
S
6
|
S
8
|
S
15
|
S
16
|
S
17
|
S
16
|
SW
16
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 600m | 16 | 20 | 32 | 42 | 42 | 41 | 41 | 40 |
| 300m | 13 | 17 | 26 | 38 | 39 | 40 | 38 | 37 |
| Valley | 11 | 15 | 22 | 35 | 35 | 37 | 36 | 35 |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 600m |
1°
|
1°
|
2°
|
4°
|
5°
|
6°
|
7°
|
8°
|
| 300m |
2°
|
3°
|
4°
|
6°
|
7°
|
8°
|
9°
|
10°
|
| Valley |
2°
|
3°
|
5°
|
7°
|
8°
|
8°
|
9°
|
10°
|
| Freezing Level |
800m
|
900m
|
1,100m
|
1,600m
|
2,600m
|
2,700m
|
2,600m
|
2,500m
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 600m |
-3°
|
-4°
|
-4°
|
-3°
|
-2°
|
0°
|
1°
|
3°
|
| 300m |
-1°
|
0°
|
1°
|
1°
|
2°
|
3°
|
5°
|
6°
|
| Valley |
0°
|
1°
|
2°
|
3°
|
4°
|
4°
|
6°
|
7°
|
Additional weather information
Meteorologist's view
Gusts of 50-55 mph likely over the higher summits for much of the day. Heavy rain will result in very wet underfoot conditions with high watercourses making any river crossings hazardous. Some flooding of footpaths and access roads is possible.
Weather
Dry through the early hours with high cloud gradually increasing from the west. Rain from soon after dawn, turning heavy late morning. Heavy rain persisting through the afternoon and much of the evening with strong winds, approaching gale force over the summits. Turning largely dry around midnight.
Chance of cloud-free hill tops
60% early morning, soon falling to nil.
Low cloud and visibility
Good visibility with cloud above the summits around dawn, but quickly lowering, bases dropping to 400m by late morning with very poor visibility for the rest of the day.
Recent rainfall
| Last 24 hours | Last 48 hours | Last 72 hours |
|---|---|---|
| 2.6mm | 25.8mm | 25.8mm |
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
Dry but cloudy through the early hours. Outbreaks of occasionally heavy rain spreads north in the morning, clearing around late afternoon or early evening. Turning dry with clear spells late evening.
Chance of cloud-free hill tops
10%
Maximum wind speed expected
Southwest becoming South around dawn, 20 gusting 30 mph. Increasing to 30 gusting 40 mph by around midday. Winds becoming Southwest in the evening.
Temperature
- At 600m Plus 6 or 7 Celsius, falling to plus 2 Celsius late evening.
- Valley Plus 6 Celsius rising to 8 Celsius.
- Freezing level Above the summits, falling to 800-900m late evening.
Low cloud and visibility
Very poor visibility with cloud extensive to lower slopes for much of the day, lifting to around 500m from mid-afternoon. Hills becoming cloud free in the evening.
Mountain weather information
Fri 19 Dec
A bright and breezy day with a few well scattered showers. Fresh southwest winds and feeling colder than recent days, although freezing level above the summits.
Sat 20 Dec
After a dry start rain will turn persistent and occasionally heavy. Strong south or southwest winds. Freezing level above the summits.
Sun 21 Dec
A generally cloudy day with hill fog and outbreaks of rain at times. Moderate generally southerly winds. Freezing level remaining above the summits.
Summit specific forecast
Mountain summit forecast map
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.