Eryri / Snowdonia Mountain weather forecast table
Confidence
Quite high for fair weather on Tuesday and occasionally unsettled otherwise, but lowering for timing detail of worst of later conditions.
This evening forecast
Fair start, then cloud and rain, initially sleety across highest peaks, reaching from the west from mid-evening, as southerly winds freshen. Freezing level lifting above the summits.
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
Heavy Persistent Rain
Thunderstorms
Mountain weather forecast
Unsettled with showers and longer periods of rain, summit snow. Gale to severe gale summit winds developing.
| 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) |
80% | 80% | 80% | 60% | 60% | 50% | 70% | 70% |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
S
22
|
S
34
|
W
37
|
W
34
|
W
36
|
W
39
|
W
40
|
NW
27
|
| 600m |
S
16
|
S
24
|
W
24
|
W
24
|
W
26
|
W
28
|
W
28
|
W
19
|
| 300m |
S
10
|
S
15
|
W
16
|
W
15
|
W
17
|
W
18
|
W
19
|
W
12
|
| Valley |
S
10
|
S
15
|
W
16
|
W
15
|
W
18
|
W
19
|
W
20
|
NW
13
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m | 27 | 41 | 46 | 43 | 47 | 51 | 53 | 37 |
| 600m | 21 | 31 | 34 | 33 | 36 | 39 | 40 | 28 |
| 300m | 18 | 27 | 30 | 28 | 31 | 34 | 36 | 23 |
| Valley | 18 | 27 | 30 | 28 | 31 | 34 | 36 | 23 |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
3°
|
3°
|
2°
|
0°
|
0°
|
1°
|
1°
|
1°
|
| 600m |
4°
|
5°
|
4°
|
3°
|
3°
|
3°
|
3°
|
3°
|
| 300m |
6°
|
7°
|
7°
|
5°
|
5°
|
5°
|
5°
|
5°
|
| Valley |
7°
|
8°
|
8°
|
7°
|
7°
|
7°
|
6°
|
6°
|
| Freezing Level |
1,400m
|
1,600m
|
1,200m
|
900m
|
900m
|
1,000m
|
1,000m
|
1,000m
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
-3°
|
-4°
|
-6°
|
-8°
|
-8°
|
-8°
|
-8°
|
-7°
|
| 600m |
0°
|
0°
|
-1°
|
-4°
|
-4°
|
-4°
|
-4°
|
-3°
|
| 300m |
3°
|
4°
|
3°
|
1°
|
1°
|
1°
|
0°
|
1°
|
| Valley |
4°
|
5°
|
4°
|
3°
|
2°
|
2°
|
2°
|
2°
|
Additional weather information
Meteorologist's view
Difficult conditions with extensive hill fog, occasionally heavy rain and summit snow coupled with gale to severe gale summit winds which brings a severe wind chill at height.
Weather
Showers and longer periods of rain, snow level lowering to 800-900m mid-morning. Outbreaks turning heavy at times, with some risk of thunder and hail, particularly either side on noon and across western areas of the park. Some limited brighter spells.
Chance of cloud-free hill tops
30%
Low cloud and visibility
Good becoming moderate or poor in rain and sleet, very poor in snow and within cloud with bases quite extensive from 700m.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Rather cloudy start with showers, snow level 700-800m. Outbreaks frequent through the morning, dwindling gradually from mid-day with bright then clear spells increasing. Fresh to strong northerly summit winds bringing a severe wind chill at height.
Chance of cloud-free hill tops
30% becoming 70% by late afternoon
Maximum wind speed expected
North 30-35mph with gusts reaching 45mph across more exposed ridges and summits.
Temperature
- At 800m Plus 1-2 Celsius
- Valley Plus 3 Celsius increasing 10 Celsius for the afternoon
- Freezing level Around 900m
Low cloud and visibility
Good becoming moderate or poor in showers, very poor within cloud with bases quite extensive from 700m at first, before turning more broken later in the day.
Mountain weather information
Tue 25 Nov
Dry with bright spells increasing through the day. Northerly summit winds initially fresh. Freezing level around 800m.
Wed 26 Nov
Dry start with some early brighter spells. Band of rain reaching from the west during the afternoon. Fresh to strong southerly winds. Freezing level soon lifting above summits.
Thu 27 Nov
Occasional rain, heavy at times. Strong to gale southwest winds. Freezing level above summits.
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.