Mountain weather
Snowdonia Mountain weather forecast table
Confidence
High confidence in dry and settled weather to end the week and over the weekend. Confidence lowers early next week with the chance of some rain by Monday night.
This evening forecast
Remaining dry this evening with plenty of sunshine to end the day and skies clearing overnight.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
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.
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.
Mountain weather forecast
Sunny and cold first thing. Patchy cloud developing but staying dry.
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
Weather (at 800m) |
|
|
|
|
|
|
|
|
Chance of precipitation (at 800m) |
00% | 00% | 00% | 00% | <05% | <05% | <05% | 00% |
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 |
SE
9
|
SE
11
|
S
6
|
SW
4
|
SW
4
|
NW
6
|
N
7
|
NE
9
|
| 600m |
SE
9
|
S
9
|
S
8
|
SW
5
|
W
4
|
NW
7
|
N
6
|
E
5
|
| 300m |
SE
7
|
SE
7
|
SE
6
|
SW
4
|
W
5
|
NW
6
|
N
5
|
E
3
|
| Valley |
SE
8
|
S
8
|
S
7
|
S
4
|
NW
6
|
NW
7
|
NW
5
|
SE
3
|
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 | 13 | 15 | 9 | 8 | 8 | 11 | 11 | 11 |
| 600m | 13 | 14 | 12 | 9 | 9 | 12 | 10 | 8 |
| 300m | 12 | 13 | 11 | 7 | 9 | 11 | 9 | 7 |
| Valley | 13 | 15 | 13 | 7 | 11 | 13 | 9 | 6 |
Altitude above mean sea level
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
| 900m |
1°
|
0°
|
0°
|
2°
|
3°
|
3°
|
2°
|
1°
|
| 600m |
3°
|
2°
|
2°
|
4°
|
5°
|
5°
|
4°
|
3°
|
| 300m |
5°
|
4°
|
3°
|
7°
|
8°
|
8°
|
7°
|
5°
|
| Valley |
6°
|
5°
|
4°
|
8°
|
9°
|
9°
|
8°
|
7°
|
| Freezing Level |
700m
|
600m
|
600m
|
700m
|
800m
|
900m
|
900m
|
900m
|
Altitude above mean sea level
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
| 900m |
-3°
|
-4°
|
-3°
|
-1°
|
1°
|
0°
|
-1°
|
-2°
|
| 600m |
0°
|
-2°
|
-2°
|
2°
|
4°
|
3°
|
2°
|
1°
|
| 300m |
2°
|
1°
|
1°
|
6°
|
7°
|
6°
|
5°
|
4°
|
| Valley |
3°
|
2°
|
1°
|
7°
|
8°
|
7°
|
6°
|
6°
|
Additional weather information
Meteorologist's view
It will feel cold on exposed ridges and summits with a relatively low freezing level. However, despite the chilly feel, the strong periods of sunshine will give moderate UV levels and therefore sun protection is advised.
Weather
After a dry and clear night, patchy mist and shallow fog may form in prone valleys around dawn. Otherwise, it will be a dry, sunny and cold start to the day with a widespread frost in valleys due to a temperature inversion. Fair weather clouds will develop from mid-morning, but there will still be lengthy sunny spells through the day and it will stay dry. Into the evening and cloud amounts will reduce to give increasing amounts of sunshine.
Chance of cloud-free mountain/hill tops at 800m
100%. Small fair weather clouds will develop but the bases of these will be above all the summits.
Visibility
Some locally poor visibilities are possible first thing in any shallow valley fog, but otherwise visibility will be excellent with distant hills and landmarks visible.
Ground conditions
Please see - https://www.eryri.llyw.cymru/visiting/walking/ground-conditions
Mountain weather information
Weather
After another dry, clear and frosty night, it will be a sunny start to the morning. Some cloud will build through the day and a veil of high cloud may cover the sky at times, however it will stay dry and bright.
Chance of cloud-free mountain/hill tops at 800m
100%. Some cloud is expected however bases will be above the summits.
Maximum wind speed expected
Southeast or south 10-15 mph
Temperature
- At 800m Plus 2 Celsius rising to plus 6 Celsius
- Valley Minus 2 Celsius rising to Plus 13 Celsius
- Freezing level 900-1000m but rising above all summits during the afternoon.
Visibility
Generally very good however some distant hills may appear a little hazy through the afternoon.
Mountain weather information
Sunday 18 April
Sunrise:
Sunset:
A dry day is expected but it is likely to be mostly cloudy. Skies will be bright with some weak periods of sunshine at times. A freshening southwesterly breeze with freezing levels mostly above the summits.
Monday 19 April
Sunrise:
Sunset:
Staying mainly dry and cloudy with a freshening south-westerly breeze.
Tuesday 20 April
Sunrise:
Sunset:
Low confidence: Perhaps some patchy light rain and summit snow during the early hours and through the morning, but probably becoming drier during the afternoon. Light to moderate winds.
Updated at:
Mountain summits
Other points of interest
Cluster of multiple stations
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.