Mountain weather

Eryri / Snowdonia

Eryri / Snowdonia Mountain weather forecast table

Confidence

High confidence for some rain and strong winds at times, but with some calmer, drier interludes. Moderate confidence for Thursday's rainfall with the potential for heavy rain and gales.

Sunrise:
Sunset:

This evening forecast

Storm Agnes brings persistent, occasionally heavy rain with a risk of thunder, easing later. Storm force, locally higher winds continuing.

Sunrise:
Sunset:
Mountain hazards

Mountain weather hazards

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

hazard 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.

hazard 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.
hazard 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.
hazard 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.
hazard 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

A blustery, mainly dry, bright day. A risk of persistent rain and strong winds later.

00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
Weather
(at 800m)
Fog Mist Cloudy Cloudy Sunny intervals Cloudy Light rain Heavy rain
Chance of precipitation
(at 800m)
30% 20% 10% 10% 10% 20% 70% 90%

Wind direction and speed (mph)
Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m SW
46
SW
41
SW
33
SW
31
SW
34
SW
34
S
33
S
28
600m SW
33
SW
29
SW
21
SW
22
SW
26
S
26
S
25
S
21
300m SW
24
SW
20
SW
13
SW
16
S
19
S
19
S
17
S
15
Valley SW
23
SW
20
SW
12
SW
13
S
17
S
18
S
16
S
14
Wind gust (mph)
Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m 60 53 43 42 47 48 46 40
600m 47 41 31 32 38 39 37 33
300m 43 38 28 29 34 35 32 29
Valley 42 36 24 24 31 33 31 27

Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m
600m
11°
10°
10°
11°
10°
10°
300m
13°
12°
11°
12°
13°
13°
12°
12°
Valley
14°
13°
13°
14°
15°
15°
14°
14°
Freezing Level
2,400m
1,900m
1,700m
1,900m
1,800m
2,000m
2,300m
2,600m

Altitude above mean sea level
00:00 03:00 06:00 09:00 12:00 15:00 18:00 21:00
900m
600m
300m
10°
10°
10°
10°
Valley
10°
10°
10°
12°
12°
12°
11°
11°

Additional weather information

Meteorologist's view

Winds on summits may exceed those indicated in the tables above, especially into the evening. Walking conditions are expected to be extremely difficult given strong winds and the possibility for heavy, persistent rain into the evening. This would be coupled with poor visibility and a notable wind chill.

Weather

Severe gale to storm force winds continuing overnight, though slowly easing. Mostly cloudy conditions expected along with some drizzle, mainly on western coastal upslopes. Largely dry and bright by day, though a chance for some occasional rain or drizzle on hills. Remaining windy, though not as strong as overnight. Turning cloudier during the afternoon, with a risk for a more persistent and widespread period of rain to develop by the evening. This could be heavy and accompanied by gale force winds on summits.

Chance of cloud-free hill tops

80%, but falling to 50% by the evening.

Low cloud and visibility

Cloud mostly above summits through the morning, but some patches likely on the highest routes at first. A chance for more widespread low cloud to develop by the evening with extensive bases 400-500m and patches below this. Visibility generally good, but becoming moderate or poor if persistent rain develops.

Ground conditions

Please see - https://snowdonia.gov.wales/visit/snowdon/yr-wyddfa-ground-conditions-reports/

Sunrise:
Sunset:

Mountain weather information

Weather

Cloud and rain clearing overnight with winds easing. Often dry and bright through the day, just a small chance of drizzle on western slopes during the morning and the odd, blustery afternoon shower developing inland.

Chance of cloud-free hill tops

80%.

Maximum wind speed expected

Westerly 20mph, gusting 30mph.

Temperature

  • At 800m Plus 8 degrees Celsius.
  • Valley Plus 11 increasing Plus 16 degrees Celsius.
  • Freezing level Above summits.

Low cloud and visibility

A few patches of cloud may cover high western summits through the morning, otherwise fine. Visibility away from any areas of morning drizzle will be very good.

Mountain weather information

Sat 30 Sep

Sunrise:
Sunset:

Largely fine to start, though a few valley mist and fog patches are possible early morning. Clouding over later with strengthening southerly winds and a chance persistent rain developing.

Sun 1 Oct

Sunrise:
Sunset:

Overnight rain and strong winds probably clearing early morning. Sunny spells and isolated blustery showers following.

Mon 2 Oct

Sunrise:
Sunset:

Probably rather breezy with a chance of showers, or a long spell of rain during the day.

Updated at:

Summit specific forecast

Mountain summit forecast map

Loading map…

The region can be divided into four areas with the northernmost area the most popular, including peaks such as Moel Hebog, Mynydd Mawr and the Nantlle Ridge. Many hikers tend to concentrate on Yr Wyddfa (Snowdon) itself regarding it as a fine mountain. However it can become quite crowded, with the peak welcoming around half a million visitors every year, of which four fifths scale the peak on foot, while the remainder choose to take the train instead.

One of Yr Wyddfa's (Snowdon) main attractions is the sheer number and variety of paths that reach the peak. This means that everyone from mountaineering novices to climbing experts should find a way up the mountain that will suit their abilities or provide them with a sufficient test. The easiest is the Llanberis path which, being the longest, has the most shallow ascent. In contrast, the Watkin Path is widely seen as being the most demanding ascent, despite also being considered the prettiest.