Mountain weather

Eryri / Snowdonia

Eryri / Snowdonia Mountain weather forecast table

Confidence

High confidence for a mostly fine dry and settled spell of weather next few days. Lower confidence for shower details during the week ahead.

Sunrise:
Sunset:

This evening forecast

Fine and dry, with sunny/clear spells this evening and after dark. Breezy on summits.

Sunrise:
Sunset:
Mountain hazards

Mountain weather hazards

Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.

hazard Strong Sunlight
Harmful UV levels from sunlight increase with altitude giving a greater risk of sunburn and eye damage, even on some overcast days. On breezy days, the cooling effect of wind on exposed skin may disguise any feeling of sunburn until it is too late. If there is snow cover, glare increases the effect of UV rays especially on the eyes. It is advisable to wear sun block, protective clothing such as a long-sleeved top and hat and have good quality eye protection.

hazard 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

Dry, sunny and warm.

00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
Weather
(at 800m)
Clear night Sunny day Sunny day Sunny day Sunny day Sunny day Sunny day Clear night
Chance of precipitation
(at 800m)
<05% <05% <05% <05% <05% <05% <05% <05%

Wind direction and speed (mph)
Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m NE
15
NE
19
E
20
NE
17
NE
15
NE
9
NE
11
NE
11
600m E
11
E
12
E
12
NE
12
NE
12
NE
8
NE
7
E
8
300m E
5
E
6
E
7
NE
6
NE
9
NE
9
N
6
E
4
Valley SE
5
E
6
E
6
NE
6
NE
8
N
8
N
4
SE
3
Wind gust (mph)
Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m 19 23 24 22 21 13 15 15
600m 14 16 17 17 18 13 10 12
300m 10 12 14 12 15 14 9 8
Valley 9 11 13 11 14 13 8 6

Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m
11°
10°
10°
11°
12°
13°
13°
11°
600m
13°
12°
12°
14°
15°
16°
15°
13°
300m
14°
13°
14°
16°
18°
18°
17°
14°
Valley
14°
14°
14°
17°
18°
18°
17°
15°
Freezing Level
2,300m
2,300m
2,200m
2,100m
1,800m
2,000m
2,100m
2,100m

Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m
10°
12°
11°
600m
10°
10°
11°
12°
14°
14°
11°
300m
13°
12°
12°
15°
16°
16°
16°
14°
Valley
14°
12°
13°
16°
16°
16°
16°
15°

Additional weather information

Meteorologist's view

Hill fog may make navigation tricky if near summits around sunrise. Sun protection (hat and sun cream) advised through the middle and latter part of the day, as UV levels will be high.

Weather

Patchy low cloud, mist and fog overnight and early morning soon clearing to leave a fine and dry day, with long spells of warm sunshine. Staying fine, dry and sunny/clear into the evening.

Chance of cloud-free hill tops

95% throughout

Low cloud and visibility

Cloud bases down to 700-800m early morning, quickly lifting above the summits soon after sunrise. Visibility will be generally poor in early cloud at elevation, otherwise, very good throughout, with good views of distant hills.

Ground conditions

Please see - https://yrwyddfa.live/

Sunrise:
Sunset:

Mountain weather information

Weather

Dry with clear skies overnight, perhaps some shallow mist and fog patches in the valleys, although these should soon clear after sunrise. Fine and dry, with long spells of sunshine throughout the day. Staying fine and dry, with prolonged sunshine/clear skies during the evening.

Chance of cloud-free hill tops

95% throughout.

Maximum wind speed expected

East to northeast 5-10mph throughout.

Temperature

  • At 800m Plus 09 Celsius, becoming Plus 13 Celsius.
  • Valley Plus 03 Celsius, becoming Plus 19 Celsius.
  • Freezing level Above the summits.

Low cloud and visibility

Cloud will remain above the summits. Visibility will be poor in early mist and valley fog early morning, until just after sunrise. Otherwise, very good with distant hills clearly visible.

Mountain weather information

Tue 21 May

Sunrise:
Sunset:

A fine and bright start for many. However, the cloud will be bubbling up to bring some showers during the afternoon, these are likely to be slow moving, heavy and possibly thundery. Warm in the sunshine. Light and variable winds. Freezing level above the summits.

Wed 22 May

Sunrise:
Sunset:

Early mist and fog patches soon lifting and clearing to leave a largely dry and bright start, with sunny spells. However, a few scattered showers are likely to develop during the afternoon. Warm in the sunshine. Light west to northwest winds. Freezing level above the summits.

Thu 23 May

Sunrise:
Sunset:

Dry and bright at first. Otherwise, another day of sunny spells and scattered showers, possibly heavy at times. Warm in the sunshine. Light northwest winds. Freezing level above the summits.

Updated at:

Summit specific forecast

Mountain summit forecast map

Loading map…