Mountain weather

Mountain weather

Eryri / Snowdonia

Confidence

High confidence in the general evolution during the next 5 days, but some uncertainty on the timing and extent of rain expected on Thursday afternoon.

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.

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.

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.
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.
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

Heavy rain clearing early, then sunny spells and showers. Summit gales.

Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
Weather symbols Heavy Rain Sunny intervals Sunny intervals Heavy rain showers Heavy rain showers Partly cloudy (night)
Chance of
precipitation
(at 800m)
Chance of precipitation
80%
20%
20%
30%
30%
10%

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 38mph knots
W
38mph
W 36mph knots
W
36mph
W 37mph knots
W
37mph
W 32mph knots
W
32mph
W 28mph knots
W
28mph
W 24mph knots
W
24mph
600m
600m W 25mph knots
W
25mph
SW 25mph knots
SW
25mph
W 28mph knots
W
28mph
W 23mph knots
W
23mph
W 16mph knots
W
16mph
W 13mph knots
W
13mph
300m
300m W 15mph knots
W
15mph
W 17mph knots
W
17mph
W 19mph knots
W
19mph
W 15mph knots
W
15mph
W 10mph knots
W
10mph
W 6mph knots
W
6mph
Valley
Valley W 15mph knots
W
15mph
W 17mph knots
W
17mph
W 19mph knots
W
19mph
W 15mph knots
W
15mph
W 10mph knots
W
10mph
W 6mph knots
W
6mph

Wind gust

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 45mph 44mph 46mph 40mph 35mph 30mph
600m
600m 32mph 33mph 36mph 30mph 24mph 20mph
300m
300m 28mph 29mph 32mph 27mph 22mph 17mph
Valley
Valley 27mph 28mph 32mph 27mph 22mph 17mph

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 4 degrees Celsius 1 degrees Celsius 1 degrees Celsius 1 degrees Celsius 1 degrees Celsius 1 degrees Celsius
600m
600m 7 degrees Celsius 6 degrees Celsius 6 degrees Celsius 6 degrees Celsius 6 degrees Celsius 6 degrees Celsius
300m
300m 11 degrees Celsius 9 degrees Celsius 9 degrees Celsius 9 degrees Celsius 9 degrees Celsius 9 degrees Celsius
Valley
Valley 12 degrees Celsius 11 degrees Celsius 11 degrees Celsius 11 degrees Celsius 11 degrees Celsius 11 degrees Celsius
Freezing Level Freezing Level
2300m
1700m
1600m
1600m
1400m
1500m

Additional weather information

Meteorologist's view

Gusts of 40-50mph will make for challenging walking conditions on tops with a risk of being blown off balance. Feeling cold in the wind.

Weather

A cold front brings heavy rain around dawn, with the odd rumble of thunder possible. This front quickly clears east leaving sunny spells and a few showers for the rest of the day, some heavy with a low risk of thunder late morning and early afternoon. Showers will then tend to ease through the rest of the afternoon. Windy with gales on tops.

Chance of cloud-free hill tops

10% at first. Rising to 80% through the morning.

Low cloud and visibility

Fairly extensive low cloud bases 300-500m on the cold front at first. Then breaking up and rising to 800-1000m during the day with plenty of gaps. Visibility becoming generally good, but occasionally poor as any showers pass.

Ground conditions

No recent ground conditions report available.

Summit specific forecast