Eryri / Snowdonia Mountain weather forecast table
Confidence
High for southeast flow persisting also for relatively unsettled, but lowering for timing detail of worst of conditions.
This evening forecast
Patchy rain turning more persistent late evening. Fresh to strong southerly summit winds. Freezing level around 1300m.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Gales
Storm Force Winds
Severe Chill Effect
Poor Visibility
Mountain weather forecast
Fair start. Periods of rain and gale to storm force winds developing for the afternoon.
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
Weather (at 800m) |
|
|
|
|
|
|
|
|
Chance of precipitation (at 800m) |
30% | 10% | <05% | 10% | 20% | 80% | 80% | 20% |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
S
31
|
S
27
|
SE
34
|
SE
48
|
SE
53
|
SE
54
|
S
41
|
S
38
|
| 600m |
S
22
|
S
20
|
SE
24
|
SE
31
|
SE
40
|
SE
41
|
S
30
|
S
26
|
| 300m |
S
15
|
S
12
|
SE
15
|
SE
22
|
SE
29
|
SE
29
|
S
21
|
SE
18
|
| Valley |
S
15
|
S
13
|
SE
15
|
SE
23
|
SE
30
|
SE
29
|
S
21
|
SE
18
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m | 36 | 32 | 40 | 57 | 65 | 66 | 51 | 46 |
| 600m | 28 | 25 | 31 | 40 | 52 | 53 | 40 | 35 |
| 300m | 26 | 21 | 28 | 39 | 49 | 48 | 37 | 31 |
| Valley | 26 | 21 | 28 | 39 | 48 | 49 | 37 | 32 |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
2°
|
1°
|
0°
|
0°
|
0°
|
2°
|
2°
|
1°
|
| 600m |
3°
|
3°
|
2°
|
2°
|
3°
|
4°
|
3°
|
3°
|
| 300m |
6°
|
4°
|
4°
|
4°
|
6°
|
6°
|
6°
|
5°
|
| Valley |
6°
|
6°
|
5°
|
5°
|
7°
|
8°
|
7°
|
6°
|
| Freezing Level |
1,200m
|
1,000m
|
800m
|
800m
|
1,200m
|
1,300m
|
1,200m
|
1,000m
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
-6°
|
-6°
|
-8°
|
-10°
|
-9°
|
-8°
|
-7°
|
-8°
|
| 600m |
-2°
|
-3°
|
-4°
|
-5°
|
-4°
|
-4°
|
-4°
|
-4°
|
| 300m |
2°
|
1°
|
0°
|
-1°
|
0°
|
1°
|
0°
|
0°
|
| Valley |
3°
|
2°
|
1°
|
0°
|
2°
|
2°
|
2°
|
2°
|
Additional weather information
Meteorologist's view
Hazardous conditions for the afternoon in with storm force summit winds gusting above 70mph, combined with extensive hill fog and summit snow. Also severe wind chill effect reaching down to mid-levels.
Weather
Hill fog and occasional rain at first overnight, turning largely dry by dawn as the cloud becomes more broken. Largely dry start to the day with occasional brighter spells appearing. Cloud thickening from the west mid to late morning bringing occasional rain, above 900m snow, from early afternoon, clearing late evening.
Chance of cloud-free hill tops
60-70% becoming 25% for the afternoon.
Low cloud and visibility
Good or very good, becoming moderate or poor in rain, very poor in snow and within cloud with bases becoming quite extensive from 800m from early afternoon.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
A dull day with occasional rain that turns heavy at times and wintry across highest peaks. Gale to severe gale southeast summit winds bringing severe wind chill.
Chance of cloud-free hill tops
10-20%
Maximum wind speed expected
Southeast mean 35-45mph with gusts reaching 55-65mph across exposed ridges and summits.
Temperature
- At 800m Plus 1 Celsius increasing 4 Celsius later
- Valley Plus 4 Celsius increasing 11 Celsius for the afternoon
- Freezing level 900-1000m lifting later
Low cloud and visibility
Good or very good, becoming moderate or poor in rain, very poor in snow and within cloud with bases quite extensive from 600m with patches lower down.
Mountain weather information
Thu 22 Jan
Dull with rain, most of this light. Strong to gale southeast summit winds bringing a severe wind chill to most. Freezing level above all summits.
Fri 23 Jan
Showers or longer periods of rain, with snow at times across highest peaks, but also some drier brighter conditions about, chiefly later in the day. Strong to gale southeast summit winds bringing a severe wind chill here. Freezing level above all summits.
Sat 24 Jan
Brighter spells and scattered showers, these wintry across higher routes. Fresh east to southeast summit winds.
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.