Mountain weather

Mountain weather

Eryri / Snowdonia

Confidence

High for overall change to more unsettled weather but low for location and intensity of rainfall throughout.

Mountain hazards

Mountain weather hazards

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

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.

Thunderstorms
Lightning is a significant mountain hazard which can result in serious injury or death. Mountain terrain often leaves one highly exposed to lightning strikes. Hail may give unpleasant conditions with torrential rain and localised flash flooding also possible, mainly in Summer months.

Mountain weather forecast

Generally dry and bright with some showers possible later.

Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
Weather symbols Cloudy Sunny intervals Light rain showers Light rain showers Cloudy Light rain showers (night)
Chance of
precipitation
(at 800m)
Chance of precipitation
10%
10%
30%
30%
20%
30%

Wind direction and speed

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m E 30mph knots
E
30mph
E 27mph knots
E
27mph
E 23mph knots
E
23mph
E 21mph knots
E
21mph
E 21mph knots
E
21mph
E 34mph knots
E
34mph
600m
600m E 15mph knots
E
15mph
E 19mph knots
E
19mph
E 18mph knots
E
18mph
E 16mph knots
E
16mph
NE 10mph knots
NE
10mph
E 19mph knots
E
19mph
300m
300m E 12mph knots
E
12mph
SE 17mph knots
SE
17mph
E 15mph knots
E
15mph
E 13mph knots
E
13mph
NE 6mph knots
NE
6mph
E 15mph knots
E
15mph
Valley
Valley E 12mph knots
E
12mph
SE 17mph knots
SE
17mph
E 15mph knots
E
15mph
E 13mph knots
E
13mph
NE 6mph knots
NE
6mph
E 14mph knots
E
14mph

Wind gust

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 36mph 33mph 30mph 28mph 27mph 43mph
600m
600m 26mph 25mph 25mph 22mph 15mph 30mph
300m
300m 24mph 27mph 24mph 21mph 11mph 28mph
Valley
Valley 24mph 26mph 24mph 21mph 12mph 27mph

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 3 degrees Celsius 5 degrees Celsius 8 degrees Celsius 11 degrees Celsius 11 degrees Celsius 7 degrees Celsius
600m
600m 8 degrees Celsius 9 degrees Celsius 12 degrees Celsius 14 degrees Celsius 16 degrees Celsius 11 degrees Celsius
300m
300m 11 degrees Celsius 12 degrees Celsius 15 degrees Celsius 17 degrees Celsius 19 degrees Celsius 14 degrees Celsius
Valley
Valley 12 degrees Celsius 13 degrees Celsius 16 degrees Celsius 19 degrees Celsius 20 degrees Celsius 16 degrees Celsius
Freezing Level Freezing Level
2000m
2800m
2900m
3200m
3200m
3200m

Additional weather information

Meteorologist's view

A fine day for any outdoor activities in the park, UV levels remaining high so sun protection advisable. There is a risk of showers through the afternoon with a low risk of some heavier bursts so waterproof may be recommended.

Weather

Some patchy cloud around the park at first but this is expected to lift and break to leave a generally dry and bight day ahead with sunshine turning hazy at times. There is a risk of some isolated showers through the late afternoon, which may have the odd heavier burst and a very low risk of the odd rumble of thunder.

Chance of cloud-free hill tops

30% quickly rising to >95%.

Low cloud and visibility

Some patchy cloud, bases above 500-600 m. This is expected to quickly lift and break with all bases soon rising above summits. Visibilities many be moderate or poor initially in cloud but very good visibilities expected outside this. Visibilities may drop to moderate in passing showers.

Ground conditions

Please see - https://yrwyddfa.live/

Summit specific forecast