Mountain weather

Mountain weather

Eryri / Snowdonia

Confidence

High for an often cloudy and humid week to come. Low for timing of any rain bands and potential for brighter spells to develop.

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.

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.
Heavy Persistent Rain
Heavy and persistent rain can lead to drenched clothing and footwear with waterproofs often becoming soaked through, especially if accompanied by strong winds. This can lead to significant loss of body heat and an increased likelihood of hypothermia. Terrain may turn increasingly boggy underfoot while streams can flood and become impassable. There may also be a risk of flooding in valleys or glens. If there is snow cover, a heightened avalanche hazard is possible and avalanche reports should be consulted where available.

Mountain weather forecast

Extensive low cloud. Intermittent light rain and drizzle becoming heavier and more persistent later.

Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
Weather symbols Drizzle Drizzle Drizzle Light rain Light rain Heavy Rain
Chance of
precipitation
(at 800m)
Chance of precipitation
30%
30%
50%
30%
50%
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 SW 20mph knots
SW
20mph
SW 22mph knots
SW
22mph
SW 27mph knots
SW
27mph
SW 30mph knots
SW
30mph
SW 29mph knots
SW
29mph
SW 28mph knots
SW
28mph
600m
600m S 18mph knots
S
18mph
S 20mph knots
S
20mph
SW 23mph knots
SW
23mph
S 21mph knots
S
21mph
S 20mph knots
S
20mph
S 19mph knots
S
19mph
300m
300m S 10mph knots
S
10mph
S 14mph knots
S
14mph
S 14mph knots
S
14mph
S 13mph knots
S
13mph
S 13mph knots
S
13mph
S 11mph knots
S
11mph
Valley
Valley S 10mph knots
S
10mph
S 14mph knots
S
14mph
S 14mph knots
S
14mph
S 13mph knots
S
13mph
S 13mph knots
S
13mph
S 12mph knots
S
12mph

Wind gust

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 23mph 26mph 33mph 37mph 36mph 35mph
600m
600m 21mph 25mph 29mph 27mph 27mph 24mph
300m
300m 17mph 21mph 24mph 24mph 23mph 21mph
Valley
Valley 17mph 20mph 23mph 23mph 23mph 21mph

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 6 degrees Celsius 5 degrees Celsius 6 degrees Celsius 6 degrees Celsius 6 degrees Celsius 6 degrees Celsius
600m
600m 7 degrees Celsius 7 degrees Celsius 8 degrees Celsius 9 degrees Celsius 9 degrees Celsius 8 degrees Celsius
300m
300m 10 degrees Celsius 11 degrees Celsius 12 degrees Celsius 12 degrees Celsius 11 degrees Celsius 11 degrees Celsius
Valley
Valley 11 degrees Celsius 13 degrees Celsius 13 degrees Celsius 13 degrees Celsius 13 degrees Celsius 12 degrees Celsius
Freezing Level Freezing Level
2900m
2200m
2400m
3400m
3600m
3500m

Additional weather information

Meteorologist's view

Views from the hills will be limited throughout Tuesday.

Weather

A widely cloudy day with persistent low cloud shrouding the summits, particularly on western-facing slopes. The small chance of a few brighter spells across the east of the park. Some outbreaks of drizzle to begin, then more persistent rain arriving from the afternoon, turning heavy for a time.

Chance of cloud-free hill tops

Mostly 20%. Potentially 40% in the east of the park during the middle of the day.

Low cloud and visibility

Persistent cloud at 300-400m on western-facing slopes, but dropping to 200m at times. Cloud may locally rise to 600-800m in the east. Moderate visibility on some lower slopes, but otherwise very poor in hill fog and rain.

Ground conditions

Please see - https://yrwyddfa.live/

Summit specific forecast