Mountain weather

Eryri / Snowdonia

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Eryri / Snowdonia Mountain weather forecast table

Confidence

High for overall story, low with respect to low cloud and fog Sunday morning and for location of showers through Sunday and Monday.

Sunrise:
Sunset:

This evening forecast

Dry and bright conditions to end the day with skies turning hazy later.

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 hazards explained

Mountain weather forecast

A cloudier day ahead with the odd spot of rain possible.

Time 00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
Weather
(at 800m)
 Partly cloudy (night) Partly cloudy (night) Cloudy Cloudy Cloudy Sunny intervals Sunny intervals Partly cloudy (night)
Chance of precipitation
(at 800m)
 <05% <05% <05% <05% <05% <05% 10% 10%

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 E
16
 SE
13
 SE
13
 S
13
 SW
13
 SW
11
 W
10
 W
8
600m SE
11
 SE
10
 S
11
 S
12
 SW
13
 W
9
 W
6
 SW
5
300m SE
6
 SE
6
 SE
5
 S
8
 SW
9
 W
6
 W
3
 W
2
Valley SE
6
 SE
7
 SE
6
 S
8
 SW
8
 NW
6
 W
3
 SW
2
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 20 16 16 17 17 15 12 10
600m 16 15 15 16 17 13 8 6
300m 14 13 11 13 14 9 5 4
Valley 14 14 12 13 13 9 5 4

Altitude above mean sea level
Time 00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m
9°
9°
9°
9°
9°
9°
9°
8°
600m
12°
11°
10°
11°
11°
12°
11°
9°
300m
12°
12°
12°
14°
14°
14°
13°
10°
Valley
13°
12°
12°
15°
15°
14°
14°
11°
Freezing Level
2,200m
2,200m
1,900m
1,900m
2,000m
2,000m
1,900m
1,800m

Altitude above mean sea level
Time 00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m
6°
6°
6°
6°
6°
7°
6°
5°
600m
9°
9°
8°
8°
9°
10°
9°
8°
300m
11°
11°
11°
12°
12°
12°
12°
10°
Valley
12°
11°
11°
13°
14°
14°
13°
11°

Additional weather information

Meteorologist's view

A great day for any outdoor activities. Feeling rather chilly at first with warmer layers recommended. Sunny intervals and moderate to high UV levels expected so sun protection is suggested.

Weather

A cloudier day ahead with the potential for low cloud on eastward facing slopes to the east of the park and the odd patch of mist and fog in sheltered valleys. Some brighter or sunny spells still possible through the morning but cloud will gradually thicken from the west which may result in the odd spot of rain through the afternoon. There is a potential that some low cloud or sea fog may effect western parts of the park from early evening onward

Chance of cloud-free hill tops

80% rising to 95%, lowering to 60% to the western side of the dark after dusk.

Low cloud and visibility

Potential for some mist and fog in sheltered valleys, or hill fog on eastward facing slopes to extreme east of park at first which should quickly lift this morning. Some low cloud, bases 200-500m may drift in off Irish sea coasts after dusk, affecting western extremes of the park. Visibility will be poor or very poor in any mist or fog at first, or in low cloud and sea fog later, but excellent otherwise, with good views over distant peaks likely, but often hazy.

Ground conditions

Please see - https://yrwyddfa.live/

Sunrise:
Sunset:

Mountain weather information

Weather

Some localised mist and fog patches possible at first in sheltered valleys, this will quickly clear to leave a bright and dry start to the day with plenty of sunny spells. There is a very low risk of some isolated showers later in the day, most likely to the east of the national park.

Chance of cloud-free hill tops

80% rising to 95%.

Maximum wind speed expected

Northeasterly 20-30mph.

Temperature

  • At 800m Plus 4 Celsius rising to Plus 7 Celsius.
  • Valley Plus 8 Celsius rising to Plus 15 Celsius.
  • Freezing level Above summits.

Low cloud and visibility

Any valley mist and fog, or sea fog, may lift briefly into low cloud before dissipating. Very good or good visibilities expected with distant hills often turning hazy. Very poor or poor visibility in mist of fog initially or in low cloud as it lifts.

Mountain weather information

Tue 28 Apr

Sunrise:
Sunset:

Dry and bright with variable amounts of cloud around throughout the day. Breezy northeasterly winds and freezing level above summits.

Wed 29 Apr

Sunrise:
Sunset:

Another dry and bright with variable amounts of cloud around throughout the day. Northeasterly winds becoming strong over summits and ridges. Freezing level above summits

Thu 30 Apr

Sunrise:
Sunset:

Settled weather persisting with more dry weather and sunny spells throughout. Moderate to fresh easterly winds, often strong over summits and ridges.

Updated at:
Mountain weather explained

Summit specific forecast

Mountain summit forecast map

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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.

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