Mountain weather

Mountain weather

Eryri / Snowdonia

Confidence

High confidence for stormy conditions, with heavy and persistent rain and gale force winds on Saturday. Moderate confidence on the strength of the strongest gusts. High confidence that it will remain windy on Sunday, but low confidence regarding showers.

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.
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.

Storm Force Winds
Storm force winds (gusts over 70mph) make walking very strenuous with any mobility virtually impossible over exposed ground. Where these conditions occur there is a high risk of being blown over and even standing may be impossible at times with a risk of being blown off one’s feet. Basic tasks such as using a map, eating, putting on extra clothing or communication become extremely difficult away from any shelter.

Mountain weather forecast

Storm Boelo brings heavy rain, poor visibility and gale force winds to the area.

Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
Weather symbols Light rain Heavy Rain Heavy Rain Heavy Rain Heavy rain showers (night) Partly cloudy (night)
Chance of
precipitation
(at 800m)
Chance of precipitation
30%
80%
80%
80%
60%
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 SW 32mph knots
SW
32mph
SW 38mph knots
SW
38mph
S 59mph knots
S
59mph
SW 55mph knots
SW
55mph
W 53mph knots
W
53mph
W 52mph knots
W
52mph
600m
600m SW 17mph knots
SW
17mph
S 26mph knots
S
26mph
S 44mph knots
S
44mph
SW 39mph knots
SW
39mph
W 36mph knots
W
36mph
W 37mph knots
W
37mph
300m
300m SW 8mph knots
SW
8mph
S 14mph knots
S
14mph
S 26mph knots
S
26mph
SW 22mph knots
SW
22mph
W 23mph knots
W
23mph
W 24mph knots
W
24mph
Valley
Valley SW 8mph knots
SW
8mph
S 14mph knots
S
14mph
S 26mph knots
S
26mph
SW 22mph knots
SW
22mph
W 23mph knots
W
23mph
W 24mph knots
W
24mph

Wind gust

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m 37mph 45mph 72mph 67mph 66mph 65mph
600m
600m 22mph 32mph 56mph 50mph 47mph 48mph
300m
300m 20mph 27mph 47mph 42mph 42mph 44mph
Valley
Valley 20mph 26mph 48mph 40mph 41mph 43mph

Altitude above mean sea level
Time
Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
900m -4 degrees Celsius -2 degrees Celsius -2 degrees Celsius 4 degrees Celsius -3 degrees Celsius -6 degrees Celsius
600m
600m 1 degrees Celsius 1 degrees Celsius 2 degrees Celsius 6 degrees Celsius 2 degrees Celsius -1 degrees Celsius
300m
300m 5 degrees Celsius 5 degrees Celsius 6 degrees Celsius 10 degrees Celsius 6 degrees Celsius 4 degrees Celsius
Valley
Valley 7 degrees Celsius 7 degrees Celsius 7 degrees Celsius 11 degrees Celsius 7 degrees Celsius 6 degrees Celsius
Freezing Level Freezing Level
1300m
1700m
2700m
3100m
1400m
1100m

Additional weather information

Meteorologist's view

A very poor day with numerous weather hazards. Gusts possibly in excess of 70mph will make walking and even standing very strenuous. Poor visibility with heavy and persistent rain will make for some very challenging navigation conditions.

Weather

Lowering cloud and outbreaks of rain developing during the morning, the rain soon turning heavy and persistent. Becoming very windy with gusts of 55 to 65mph can be expected over summits, perhaps in excess of 70mph at times in exposed locations during the afternoon and evening. The wind will have a buffeting effect with the risk of being blown over. The rain clears after sunset with clear and dry spells developing overnight.

Chance of cloud-free hill tops

10% during the day, becoming 70% by late evening and overnight.

Low cloud and visibility

Low cloud becoming extensive during daylight hours, obscuring summits above 200 to 400m, perhaps lower in heavy outbreaks of rain. Visibility often moderate to very poor during daylight hours, improving overnight once the cloud and rain has cleared.

Ground conditions

No recent ground conditions report available.

Summit specific forecast