Eryri / Snowdonia Mountain weather forecast table
Confidence
High for general developments. Medium for cloud details.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Gales
Severe Chill Effect
Poor Visibility
Storm Force Winds
Blizzards
Heavy Persistent Snow
Thunderstorms
Heavy Persistent Rain
Mountain weather forecast
Rain then heavy wintry showers. Very windy with severe wind chill.
06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
---|---|---|---|---|---|---|
Weather (at 800m) |
||||||
Chance of precipitation (at 800m) |
90% | 70% | 30% | 60% | 60% | 60% |
06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
---|---|---|---|---|---|---|
900m |
SW
46
|
SW
51
|
W
38
|
W
41
|
W
47
|
W
38
|
600m |
SW
34
|
SW
35
|
W
26
|
W
27
|
W
31
|
W
29
|
300m |
SW
21
|
SW
23
|
W
17
|
W
18
|
W
22
|
W
20
|
Valley |
SW
21
|
SW
23
|
W
18
|
W
19
|
W
23
|
W
21
|
06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
---|---|---|---|---|---|---|
900m | 55 | 60 | 48 | 52 | 60 | 49 |
600m | 41 | 44 | 35 | 37 | 43 | 40 |
300m | 34 | 39 | 31 | 33 | 40 | 36 |
Valley | 35 | 39 | 31 | 33 | 40 | 37 |
06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
---|---|---|---|---|---|---|
900m |
4°
|
6°
|
3°
|
2°
|
0°
|
-1°
|
600m |
6°
|
7°
|
6°
|
4°
|
3°
|
2°
|
300m |
7°
|
9°
|
8°
|
7°
|
5°
|
4°
|
Valley |
9°
|
10°
|
9°
|
8°
|
7°
|
6°
|
Freezing Level |
2,100m
|
1,800m
|
1,100m
|
1,000m
|
900m
|
700m
|
06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
---|---|---|---|---|---|---|
900m |
-4°
|
-2°
|
-5°
|
-7°
|
-9°
|
-10°
|
600m |
-1°
|
2°
|
0°
|
-2°
|
-4°
|
-6°
|
300m |
3°
|
5°
|
4°
|
2°
|
0°
|
-1°
|
Valley |
4°
|
6°
|
6°
|
4°
|
2°
|
1°
|
Additional weather information
Meteorologist's view
Note the wind speeds and significant wind chill at height with buffeting. Gusts of around 70mph possible over the summits.
Weather
Low cloud and outbreaks of rain and drizzle into Saturday morning. Cloud beginning to lift and break from late-morning. Bright or sunny spells and heavy blustery showers during the afternoon, these turning to snow over the summits. Further heavy snow and hail showers in the evening.
Chance of cloud-free hill tops
10% overnight and early morning, rising to 60% during the day, but lowering significantly as the showers pass through.
Low cloud and visibility
Extensive cloud, base 300 to 600m Saturday morning. This lifting and breaking near the summits by midday. However, falling significantly, base 400m or less as the heavy, blustery showers push through. Mostly moderate to very poor visibility becoming mostly very good or excellent as the cloud lifts and breaks, lowering significantly in showers and temporary blizzard and whiteout conditions as the heavy snow showers push through late in the day.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Heavy snow showers overnight and during the morning with some drifting and whiteout conditions. The snow showers becoming more scattered through the afternoon and evening with sunny or clear spells developing. Stormy over the summits.
Chance of cloud-free hill tops
30% becoming 70% by dusk
Maximum wind speed expected
West or Northwest 50mph gusting around 70mph with severe wind chill, buffeting and the risk of being blow over.
Temperature
- At 800m Minus 2 to Minus 4 degrees Celsius.
- Valley Zero rising to Plus 6 degrees Celsius.
- Freezing level Around 500m for much of Sunday.
Low cloud and visibility
Extensive cloud around the summits overnight and during the morning, broken bases falling to 400m or less in heavy snow showers. Cloud becoming well scattered or clear at times during the afternoon and evening. Visibility very poor in snow with white out and blizzard conditions, but becoming mostly very good or excellent in the afternoon.
Mountain weather information
Mon 23 Dec
Clear and cold at first. Rain and snow developing, rain at all levels by evening with a thaw setting in. Fresh to strong northwest, becoming southwest winds at height. Freezing most levels at first, rising above the summits by evening.
Tue 24 Dec
Cloudy with occasional rain and drizzle. Fresh to strong southwesterly winds at height. Mild.
Wed 25 Dec
Mostly cloudy. Patchy rain and drizzle. Strong to gale force southwesterly winds at height. Mild.
Summit specific forecast
Mountain summit forecast map
The Eryri (Snowdonia) mountains are made up of 90 mountain peaks including the tallest mountain in Wales, Yr Wyddfa (Snowdon), standing at 1,085 metres.