Close window

Snowdonia - Mountain weather forecast

Weather warnings

Warnings affecting Snowdonia over the next 5 days


High confidence of extensive hill fog and drizzly or wet conditions throughout the weekend.

  • Saturday
  • Sunday
  • Further outlook

Saturday 18 August 2018

Weather hazards

Poor visibility High likelihood Hide detail

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.

Learn more about poor visibility

Gales Medium likelihood Show detail

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.

Learn more about gales

Heavy persistent rain Low likelihood Show detail

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.

Learn more about heavy persistent rain


A cloudy day with patchy light rain and drizzle particularly in the west of Snowdonia, plenty hill fog, strong and gusty southwesterly winds easing slightly later in the day.


06:00 09:00 12:00 15:00 18:00 21:00
Weather at 800m Fog Fog Fog Fog Fog Drizzle
Chance of precipitation at 800m 70% 70% 80% 70% 60% 50%

Wind speed and direction

06:00 09:00 12:00 15:00 18:00 21:00
Altitude above mean sea level
900m SW 24 29 SW 27 33 SW 25 32 SW 29 37 SW 32 40 SW 35 44
600m SW 19 24 SW 23 28 SW 21 28 SW 23 30 SW 23 31 SW 24 32
300m SW 10 18 SW 13 23 SW 12 24 SW 13 27 SW 13 25 SW 13 26
Valley SW 10 19 SW 13 23 SW 12 25 SW 13 27 SW 13 25 SW 13 26


06:00 09:00 12:00 15:00 18:00 21:00
Altitude above mean sea level
900m 10 ° 11 ° 11 ° 12 ° 13 ° 13 °
600m 12 ° 12 ° 13 ° 14 ° 14 ° 14 °
300m 13 ° 14 ° 16 ° 16 ° 16 ° 16 °
Valley 15 ° 16 ° 17 ° 18 ° 17 ° 17 °

Feels like temperature

06:00 09:00 12:00 15:00 18:00 21:00
Altitude above mean sea level
900m 6 ° 6 ° 7 ° 8 ° 8 ° 8 °
600m 8 ° 9 ° 10 ° 10 ° 11 ° 10 °
300m 12 ° 12 ° 14 ° 14 ° 14 ° 14 °
Valley 13 ° 14 ° 15 ° 16 ° 15 ° 15 °

Freezing level

06:00 09:00 12:00 15:00 18:00 21:00
Freezing level i 3,600 m 3,500 m 3,500 m 3,300 m 3,000 m 3,200 m
Sunrise: 06:02
Sunset: 20:38
Moon phase: First quarter


Generally an overcast day with cloud lower4ing and thickening for some patchy light rain or drizzle at times. Some breaks in the cloud are likely in the south or east of the Snowdonia National Park. Cloud thinning and lifting slightly for a time in the afternoon but soon returning in the evening. Rain also becoming heavier and more persistent later in the evening.

Chance of cloud-free mountain/hill tops at 800m

Less than 20% in the west increasing to 40% in the east, there may be some brief breaks in the cloud by mid afternoon with some near views possible.


Visibility will be occasionally moderate below 300 metres with some near views. It will be generally poor or very poor again later in the evening.

Meteorologist's view

Gale force gusts later in the day on higher peaks.

Ground conditions

No recent ground conditions report available.

Sunday 19 August 2018

Sunrise: 06:03
Sunset: 20:36
Moon phase: First quarter


An area of heavy rain will move across Snowdonia in the early morning on Sunday. The rain area will move through quite quickly and will be heavy and persistent for a few hours in the morning. By late morning rain will become lighter but it may remain misty with some drizzle. During the afternoon conditions will improve but it will stay mainly cloudy although some summits will begin to clear of cloud particularly in the east. By nightfall there will be some breaks in the cloud.

Maximum wind speed expected

Southwesterly 25-35mph with gusts around 35-45mph, winds will ease in the evening becoming Westerly around 10mph. Gales are likely on the higher peaks in the morning.

Chance of cloud-free mountain/hill tops at 800m

Very little chance of cloud free mountain tops until late afternoon, by late evening 60% chance of cloud free tops particularly in the east.


  • At 800m Plus 13 Celsius
  • Valley Plus 16 Celsius rising to plus 18.
  • Freezing level Above summits


Becoming poor or very poor in heavy rain. Visibility will improve to moderate again by late afternoon and then become good with some late views possible by early evening.

Monday 20 August 2018

Sunrise: 06:05
Sunset: 20:33
Moon phase: First quarter

Generally cloudy with outbreaks of drizzle and mainly light rain, but better in eastern areas with occasional bright spells. Light or moderate, locally fresh southwesterly winds.

Tuesday 21 August 2018

Sunrise: 06:07
Sunset: 20:31
Moon phase: First quarter

Some early morning mist and fog will clear to give a bright, often dry day with some breaks in the cloud developing. Occasional rain is possible later. Light southwesterly winds, possibly becoming fresh or strong later.

Wednesday 22 August 2018

Sunrise: 06:08
Sunset: 20:29
Moon phase: Waxing gibbous

A band of rain may clear southwards, then indications are for some sunny spells and few showers, low confidence at this stage.

Issued at:
Close window

The Snowdonia mountains are made up of 90 mountain peaks including the tallest mountain in Wales, Snowdon, standing at 1,085 metres.

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 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 Snowdon’s 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.

Follow us on

Facebook, Twitter, YouTube, Instagram, Snapchat, or LinkedIn Facebook Follow @metoffice on Twitter YouTube Instagram Snapchat LinkedIn