Mountain weather

Mountain weather

Eryri / Snowdonia

Confidence

High for generally settled conditions to persist through the period. Low for extent of low cloud amounts on Thursday morning and extent of fog risk on Sunday and Monday.

Sunrise: Sunset:
Sunrise: Sunset:
Mountain hazards

Mountain weather hazards

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

Severe Chill Effect
Wind significantly lowers the ‘feels-like’ temperature relative to the actual temperature, with even moderate winds significantly adding to the chilling effect. Strong winds can result in a severe and debilitating wind chill many degrees below the actual temperature. This effect will be enhanced in rain or wet snow. Without protection, prolonged exposure could result in frost nip or frostbite on exposed parts of the body and/or hypothermia.

Gales
Gale force winds (gusts over 50mph) make walking difficult and strenuous with a potential to be blown over by gusts. There is often a marked increase in winds through cols or on exposed ridges and summits. Distances can take longer to cover and compass bearings become harder to follow accurately.
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

Largely dry and cloudy with fresh to strong easterly winds.

Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
Weather symbols Cloudy Cloudy Cloudy Cloudy Cloudy Cloudy
Chance of
precipitation
(at 800m)
Chance of precipitation
40%
30%
20%
30%
20%
20%

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 34mph knots
E
34mph
E 39mph knots
E
39mph
E 29mph knots
E
29mph
E 26mph knots
E
26mph
E 25mph knots
E
25mph
E 23mph knots
E
23mph
600m
600m NE 14mph knots
NE
14mph
E 21mph knots
E
21mph
E 19mph knots
E
19mph
E 11mph knots
E
11mph
E 9mph knots
E
9mph
E 8mph knots
E
8mph
300m
300m NW 6mph knots
NW
6mph
E 9mph knots
E
9mph
E 10mph knots
E
10mph
S 4mph knots
S
4mph
E 5mph knots
E
5mph
E 5mph knots
E
5mph
Valley
Valley NW 6mph knots
NW
6mph
E 9mph knots
E
9mph
E 10mph knots
E
10mph
S 4mph knots
S
4mph
E 4mph knots
E
4mph
E 5mph knots
E
5mph

Wind gust

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 39mph 47mph 36mph 32mph 30mph 29mph
600m
600m 18mph 30mph 26mph 17mph 15mph 15mph
300m
300m 9mph 22mph 21mph 11mph 12mph 12mph
Valley
Valley 9mph 21mph 21mph 11mph 11mph 12mph

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m -5 degrees Celsius -6 degrees Celsius -6 degrees Celsius -5 degrees Celsius -5 degrees Celsius -5 degrees Celsius
600m
600m 0 degrees Celsius -1 degrees Celsius -1 degrees Celsius 1 degrees Celsius 1 degrees Celsius 1 degrees Celsius
300m
300m 5 degrees Celsius 5 degrees Celsius 4 degrees Celsius 6 degrees Celsius 5 degrees Celsius 5 degrees Celsius
Valley
Valley 7 degrees Celsius 7 degrees Celsius 6 degrees Celsius 8 degrees Celsius 7 degrees Celsius 7 degrees Celsius
Freezing Level Freezing Level
1200m
1100m
1400m
1200m
1200m
1200m

Additional weather information

Meteorologist's view

A brisk easterly wind and cold temperatures are likely to bring significant wind chill to those walking at height, as well as the risk of gusts over 50 mph over exposed ridges thus care and suitable clothing is advised. Early morning hill fog has potential to make traversing over and around summits difficult at times so good navigational skills will be required for early risers.

Weather

Clear spells and patchy cloud in low lying areas through the early morning with a risk of isolated hill fog over summits. Cloud then spreads across the area from the east and persists through the rest of the day. Mostly dry with a low risk of isolated patches of drizzle in the afternoon. Feeling cold at height.

Chance of cloud-free hill tops

30% in the early morning rising to 80%.

Low cloud and visibility

Good visibilities expected outside patchy hill fog (above 600 M) which is expected to clear gradually through the morning. A risk of visibilities dropping to poor in drizzle in the afternoon.

Ground conditions

No recent ground conditions report available.

Summit specific forecast