Mountain weather

Mountain weather

Eryri / Snowdonia

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Confidence

Very high for the very warm and settled period to last until at least mid-week.

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.
Updated: 
Mountain hazards explained

Mountain weather forecast

Hazy at first, then strong sunshine and blue skies and becoming very warm.

Time
 Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
 Weather symbols Sunny Sunny Sunny Sunny Sunny Clear night
Chance of
precipitation
(at 800m)
 Chance of precipitation
<5%
<5%
<5%
<5%
<5%
<5%

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 W 4mph knots
W
4mph
 W 7mph knots
W
7mph
 SW 10mph knots
SW
10mph
 SW 10mph knots
SW
10mph
 SW 9mph knots
SW
9mph
 SE 13mph knots
SE
13mph
600m
 600m S 8mph knots
S
8mph
 SW 8mph knots
SW
8mph
 SW 11mph knots
SW
11mph
 SW 10mph knots
SW
10mph
 S 8mph knots
S
8mph
 S 10mph knots
S
10mph
300m
 300m SW 4mph knots
SW
4mph
 W 3mph knots
W
3mph
 SW 6mph knots
SW
6mph
 SW 5mph knots
SW
5mph
 SW 3mph knots
SW
3mph
 SE 4mph knots
SE
4mph
Valley
 Valley SW 5mph knots
SW
5mph
 SW 3mph knots
SW
3mph
 SW 6mph knots
SW
6mph
 W 5mph knots
W
5mph
 S 4mph knots
S
4mph
 SE 4mph knots
SE
4mph

Wind gust

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

Altitude above mean sea level
Time
 Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
 900m 10 degrees Celsius 10 degrees Celsius 12 degrees Celsius 13 degrees Celsius 14 degrees Celsius 12 degrees Celsius
600m
 600m 10 degrees Celsius 12 degrees Celsius 13 degrees Celsius 15 degrees Celsius 16 degrees Celsius 14 degrees Celsius
300m
 300m 12 degrees Celsius 15 degrees Celsius 17 degrees Celsius 18 degrees Celsius 19 degrees Celsius 17 degrees Celsius
Valley
 Valley 12 degrees Celsius 16 degrees Celsius 18 degrees Celsius 19 degrees Celsius 19 degrees Celsius 17 degrees Celsius
Freezing Level Freezing Level
1900m
2100m
2400m
2800m
3000m
3300m

Additional weather information

Meteorologist's view

South and east facing slopes will quickly warm up in the strong sunshine and it will feel hot for walking by late morning. UV levels will become high and perhaps briefly very high near the summits so sun protection and staying hydrated is recommended.

Weather

Early high cloud may make the sunshine a little hazy first thing, but otherwise blue skies for most of the day with strong sunshine and high or very high UV levels.

Chance of cloud-free hill tops

Greater than 95%.

Low cloud and visibility

Banks or ribbons of cloud are possible on lower to middle slopes in the west, above 150-200m with the top of the cloud no higher than 400-500m, this rapidly clearing to leave little if any cloud from mid-morning. Visibility generally good but locally poor in cloud first thing. Distant hills are likely to remain quite hazy.

Ground conditions

Please see - https://yrwyddfa.live/

Summit specific forecast

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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