Mountain weather
Eryri / Snowdonia Mountain weather forecast table
Confidence
High for generally mild and occasionally unsettled weather. Lowering confidence for the timing detail of the worst of the conditions.
This evening forecast
Area of rain spreading from the west. Southerly gales easing towards midnight. Freezing level above summits.
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.
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
A mainly dry, occasionally bright day. Winds increasing fresh to strong for the afternoon.
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
Weather (at 800m) |
|
|
|
|
|
|
|
|
Chance of precipitation (at 800m) |
80% | 80% | 40% | 10% | 10% | 10% | 20% | 20% |
Wind direction and speed (mph)
Altitude above mean sea level
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
SW
38
|
W
12
|
W
12
|
SW
14
|
SW
19
|
SW
23
|
SW
24
|
SW
26
|
| 600m |
S
27
|
SW
9
|
W
7
|
SW
8
|
SW
13
|
SW
14
|
S
15
|
SW
15
|
| 300m |
S
16
|
SW
6
|
SW
3
|
S
4
|
SW
7
|
SW
9
|
S
9
|
SW
9
|
| Valley |
S
16
|
SW
6
|
SW
4
|
S
4
|
SW
7
|
SW
8
|
S
9
|
SW
9
|
Wind gust (mph)
Altitude above mean sea level
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m | 45 | 15 | 15 | 17 | 24 | 29 | 31 | 33 |
| 600m | 34 | 12 | 9 | 12 | 18 | 19 | 21 | 23 |
| 300m | 29 | 10 | 6 | 9 | 15 | 18 | 19 | 21 |
| Valley | 29 | 10 | 6 | 10 | 14 | 17 | 19 | 21 |
Altitude above mean sea level
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
5°
|
3°
|
3°
|
2°
|
2°
|
2°
|
2°
|
2°
|
| 600m |
7°
|
5°
|
5°
|
4°
|
5°
|
5°
|
4°
|
4°
|
| 300m |
9°
|
7°
|
6°
|
6°
|
7°
|
7°
|
6°
|
6°
|
| Valley |
10°
|
8°
|
7°
|
7°
|
9°
|
9°
|
7°
|
7°
|
| Freezing Level |
1,800m
|
1,400m
|
1,100m
|
900m
|
1,000m
|
1,100m
|
1,100m
|
1,100m
|
Altitude above mean sea level
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
-2°
|
-1°
|
-2°
|
-3°
|
-3°
|
-4°
|
-4°
|
-5°
|
| 600m |
2°
|
2°
|
2°
|
1°
|
1°
|
1°
|
0°
|
0°
|
| 300m |
6°
|
5°
|
5°
|
4°
|
5°
|
5°
|
3°
|
3°
|
| Valley |
7°
|
6°
|
6°
|
6°
|
7°
|
6°
|
5°
|
5°
|
Additional weather information
Meteorologist's view
Severe wind chill at height increasing later as winds strengthen.
Weather
Rain overnight, occasionally turning heavy. Rain clearing early morning to leave largely dry and bright conditions from mid-morning and through the afternoon. Some limited showers developing during the evening.
Chance of cloud-free hill tops
30% at dawn, 80% from late morning
Low cloud and visibility
Good or very good becoming moderate or poor in early rain or later showers, very poor within cloud, which will be quite extensive at 600m around dawn, then lifted and well broken from mid-morning.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Fair conditions for the morning and early afternoon, then cloud reaching from the northwest later in the day, bringing the risk of some patchy evening rain. Summit winds increasing severe gale to storm force by mid-afternoon.
Chance of cloud-free hill tops
80% becoming 60% by late afternoon
Maximum wind speed expected
Southwest increasing mean 60mph by mid-afternoon with gusts reaching 80mph across more exposed ridges and summits.
Temperature
- At 800m Plus 3 Celsius
- Valley Plus 4 Celsius increasing 11 Celsius for the afternoon
- Freezing level Above summits
Low cloud and visibility
Good or very good becoming moderate or poor in rain, very poor within cloud with bases occasionally lowering 800m, increasingly so by late afternoon.
Mountain weather information
Sun 14 Dec
Sunrise:
Sunset:
Occasional rain, heavier and more persistent during the afternoon and evening. Severe gale to storm force summit winds. Freezing level above all summits.
Mon 15 Dec
Sunrise:
Sunset:
Further occasionally heavy rain. Strong to gale summit winds. Freezing level above all summits.
Tue 16 Dec
Sunrise:
Sunset:
Showers and limited brighter spells. Strong summit winds. Freezing level above all summits.
Updated at:
Summit specific forecast
Mountain summit forecast map
Loading map…
Key
Mountain summits
Other points of interest
Cluster of multiple stations
The Eryri (Snowdonia) mountains are made up of 90 mountain peaks including the tallest mountain in Wales, Yr Wyddfa (Snowdon), standing at 1,085 metres.