Mountain weather

Mountain weather

Eryri / Snowdonia

Confidence

Moderate confidence for any rainfall Saturday daytime, but this confidence increasing overnight. Also high confidence for this to clear through Sunday, but low for the extent and persistence of any showers that follow. Confidence is then high for the general story through the following week, however cloud amounts and extent of any rain or showers remains low confidence.

Mountain hazards

Mountain weather hazards

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

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.
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.

Mountain weather forecast

A dry and bright start with cloud and rain arriving from the north through the day.

Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
Weather symbols Sunny Sunny intervals Light rain showers Light rain showers Light rain Light rain
Chance of
precipitation
(at 800m)
Chance of precipitation
10%
20%
20%
20%
30%
50%

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 25mph knots
W
25mph
W 28mph knots
W
28mph
SW 27mph knots
SW
27mph
W 22mph knots
W
22mph
W 23mph knots
W
23mph
W 20mph knots
W
20mph
600m
600m SW 13mph knots
SW
13mph
W 20mph knots
W
20mph
SW 19mph knots
SW
19mph
SW 17mph knots
SW
17mph
W 14mph knots
W
14mph
W 12mph knots
W
12mph
300m
300m SW 4mph knots
SW
4mph
W 13mph knots
W
13mph
SW 12mph knots
SW
12mph
SW 10mph knots
SW
10mph
W 9mph knots
W
9mph
W 7mph knots
W
7mph
Valley
Valley SW 5mph knots
SW
5mph
W 14mph knots
W
14mph
SW 12mph knots
SW
12mph
SW 11mph knots
SW
11mph
W 9mph knots
W
9mph
W 7mph knots
W
7mph

Wind gust

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 28mph 35mph 33mph 28mph 29mph 25mph
600m
600m 16mph 26mph 25mph 22mph 19mph 17mph
300m
300m 11mph 22mph 21mph 18mph 16mph 13mph
Valley
Valley 11mph 22mph 22mph 19mph 16mph 13mph

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 6 degrees Celsius 7 degrees Celsius 5 degrees Celsius 7 degrees Celsius 8 degrees Celsius 9 degrees Celsius
600m
600m 10 degrees Celsius 10 degrees Celsius 9 degrees Celsius 10 degrees Celsius 11 degrees Celsius 12 degrees Celsius
300m
300m 14 degrees Celsius 14 degrees Celsius 13 degrees Celsius 14 degrees Celsius 14 degrees Celsius 14 degrees Celsius
Valley
Valley 15 degrees Celsius 15 degrees Celsius 14 degrees Celsius 15 degrees Celsius 16 degrees Celsius 16 degrees Celsius
Freezing Level Freezing Level
3200m
3400m
3600m
3500m
3200m
3400m

Additional weather information

Meteorologist's view

Fine conditions early on, with spells strong sunshine and appropriate sun protection required. However, cloud will thicken with conditions deteriorating later in the day, leading to some wetter descents. Don't forget to pack the waterproofs.

Weather

After a bright start turning increasingly cloudy with a chance of occasional light showers. More persistent spells of rain are likely to arrive from mid-afternoon, with cloud also descending onto the slopes to obscure many higher routes. Winds also strengthening.

Chance of cloud-free hill tops

90% dropping to 20% through the afternoon.

Low cloud and visibility

Limited cloud initially with any cloud above summits and very good or excellent visibilities expected. Through the morning cloud will lower to obscure hills above 600m, with some patches possible as low as 400m. Outside of cloud, any rain will lead to visibilities falling to moderate.

Ground conditions

Please see - https://yrwyddfa.live/

Summit specific forecast