Mountain weather
Eryri / Snowdonia Mountain weather forecast table
Confidence
High for mainly dry and bright weather on Thursday. Generally high for the weather setup from Friday onwards but some uncertainty in day-to-day cloud and rain detail.
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
Mainly dry. Feeling cold.
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
Weather (at 800m) |
|
|
|
|
|
|
Chance of precipitation (at 800m) |
10% | 10% | 30% | 40% | 40% | 30% |
Wind direction and speed (mph)
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
SW
30
|
SW
27
|
S
13
|
S
6
|
SE
6
|
S
11
|
| 600m |
SW
19
|
S
15
|
S
11
|
S
5
|
SE
6
|
S
10
|
| 300m |
SW
11
|
S
9
|
S
6
|
S
3
|
SE
4
|
S
6
|
| Valley |
SW
11
|
S
9
|
S
7
|
S
3
|
SE
4
|
S
7
|
Wind gust (mph)
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m | 35 | 32 | 16 | 7 | 7 | 14 |
| 600m | 25 | 19 | 14 | 6 | 8 | 13 |
| 300m | 23 | 17 | 11 | 5 | 7 | 11 |
| Valley | 24 | 17 | 11 | 5 | 7 | 12 |
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
1°
|
0°
|
0°
|
1°
|
0°
|
0°
|
| 600m |
3°
|
2°
|
3°
|
3°
|
2°
|
2°
|
| 300m |
5°
|
4°
|
5°
|
6°
|
4°
|
3°
|
| Valley |
6°
|
5°
|
7°
|
7°
|
5°
|
4°
|
| Freezing Level |
900m
|
800m
|
900m
|
900m
|
800m
|
800m
|
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
-7°
|
-7°
|
-5°
|
-2°
|
-3°
|
-5°
|
| 600m |
-3°
|
-2°
|
-1°
|
1°
|
-1°
|
-2°
|
| 300m |
1°
|
1°
|
3°
|
4°
|
2°
|
1°
|
| Valley |
2°
|
2°
|
5°
|
6°
|
3°
|
1°
|
Additional weather information
Meteorologist's view
A fairly mild day in the valleys but much colder with a significant wind chill on the tops, especially in the morning. Note the small chance of some persistent rain, sleet or snow for a time later so please keep updated on the forecast.
Weather
A mainly dry day with bright spells but the chance of the odd isolated shower, wintry above 700m. There is a small chance of more persistent rain, with snow above 600m late afternoon into the evening, but this is expected to pass to the east of the area.
Chance of cloud-free hill tops
30% at first becoming 60% by the morning, lowering to 20% after dark..
Low cloud and visibility
Mainly good visibility during the day with just patchy cloud above 600m, mainly in the west. A chance of low cloud becoming more extensive for a time through the evening.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
A mixture of clear or bright intervals and showers, wintry above 700m. A small chance of hail and thunder at times.
Chance of cloud-free hill tops
60%.
Maximum wind speed expected
South 20-25mph gusts 35mph.
Temperature
- At 800m Plus 1C.
- Valley Plus 2C rising to 7 or 8C.
- Freezing level 900m.
Low cloud and visibility
Occasional cloud above 500 or 600m, otherwise visibility mainly good but poor at times as showers pass through. Less than 1km in any snow showers on the tops.
Mountain weather information
Sat 17 Jan
Sunrise:
Sunset:
A lot of low cloud with best of any brightness in the north. A few showers possible, wintry on the tops. Light southeast winds. Freezing level 900m.
Sun 18 Jan
Sunrise:
Sunset:
Areas of low cloud in the morning with a few showers around, wintry on the tops. Becoming dry and bright in the afternoon. Light southerly winds becoming strong later. Freezing level 900m.
Mon 19 Jan
Sunrise:
Sunset:
A band of rain and summit snow is likely to move east followed by showers. Strong winds are likely for a time.
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.