Mountain weather

Snowdonia

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Snowdonia Mountain weather forecast table

Confidence

High for settled start to the week. Moderate for precipitation detail from Thursday onwards.

This evening forecast

Sunrise:
Sunset:

Remaining dry with clear skies. Some mist and fog patches may begin to form in the very final couple of hours of the day.

Sunrise:
Sunset:
Mountain hazards

Mountain weather hazards

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

hazard Strong sunlight
Harmful UV levels from sunlight increase with altitude giving a greater risk of sunburn and eye damage, even on some overcast days. On breezy days, the cooling effect of wind on exposed skin may disguise any feeling of sunburn until it is too late. If there is snow cover, glare increases the effect of UV rays especially on the eyes. It is advisable to wear sun block, protective clothing such as a long-sleeved top and hat and have good quality eye protection.
Mountain hazards explained

Mountain weather forecast

Fine and dry with long sunny intervals.

Wind direction and speed (mph)
Altitude above mean sea level
Wind gust (mph)
Altitude above mean sea level

Altitude above mean sea level

Altitude above mean sea level

Additional weather information

Meteorologist's view

A lovely day for being out on the hills. Be aware that, although UV levels are at moderate levels, it is still important to protect exposed areas of skin if out in the sun for extended periods of time.

Weather

Clear skies overnight into Monday. Any mist and fog patches that form in the early hours should clear shortly after sunrise. A fine and dry day follows with long intervals of sunshine. Clear spells continuing into the late afternoon, though more cloud building through the evening and into the night.

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

90% or better for much of the day. Dropping to 70% in the final few hours.

Visibility

Poor in any early mist and fog patches. Very good through the rest of the morning and afternoon with any cloud remaining above the summits and good views of surrounding hills. Some low cloud may begin to affect north-western slopes through the evening and night, reducing visibility in these areas as cloud bases occasionally drop to 700m.

Ground conditions

Please see - https://www.eryri.llyw.cymru/visiting/walking/ground-conditions

Sunrise:
Sunset:

Mountain weather information

Weather

A cloudy start to Tuesday with some misty and foggy conditions on the summits and the outside chance of some drizzle. This cloud will lift through the first half of the morning. Remaining dry from then on as the cloud begins to clear through the afternoon. These clear intervals continuing into the evening and night.

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

40% first thing, rising to 70% or better by mid-morning.

Maximum wind speed expected

Winds on the summits initially south-westerly 8mph, strengthening to 18mph and gusting 28mph by the evening.

Temperature

  • At 800m Plus 7 Celsius, rising to plus 9 Celsius.
  • Valley Plus 9, rising to plus 19.
  • Freezing level Above the summits.

Visibility

Poor on the summits to begin with in low cloud, with bases down to 500-600m. Improving through the morning as cloud lifts to above the summits, with good visibility of surrounding hills from then on.

Mountain weather information

Wednesday 22 September

Sunrise:
Sunset:

Cloud increasing ahead of a band of rain that will begin to move across the park around the middle of the day. Moderate to fresh south-westerlies on the summits.

Thursday 23 September

Sunrise:
Sunset:

Most likely unsettled with a chance of showers and longer spells of rain at times. Fresh to strong westerly winds on the summits.

Friday 24 September

Sunrise:
Sunset:

Dry at first with sunny spells. However, rain, locally heavy and persistent, will arrive through the afternoon. A fresh westerly breeze on the hills.

Updated at:
Mountain weather explained

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.

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