Eryri / Snowdonia Mountain weather forecast table
Confidence
High confidence for an unsettled and changeable period of weather. Lower for rain or snow detail so please keep updated on the forecast.
This evening forecast
Dry with clear spells. Fresh westerly winds with a severe wind chill on the tops. Freezing level 800m.
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
Blizzards
Heavy Persistent Snow
Storm Force Winds
Thunderstorms
Mountain weather forecast
Mostly dry morning. Rain, sleet and summit snow arriving with very strong winds in 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% | 30% | 20% | 10% | 10% | >95% | >95% | >95% |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
SW
23
|
SW
23
|
S
21
|
S
30
|
S
47
|
SE
48
|
S
49
|
S
37
|
| 600m |
SW
15
|
S
15
|
S
16
|
S
23
|
S
34
|
SE
36
|
SE
36
|
S
26
|
| 300m |
SW
9
|
S
9
|
S
10
|
S
15
|
S
23
|
SE
26
|
SE
26
|
S
17
|
| Valley |
SW
9
|
S
10
|
S
10
|
S
15
|
S
24
|
SE
27
|
SE
27
|
S
16
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m | 28 | 28 | 25 | 36 | 57 | 61 | 63 | 48 |
| 600m | 20 | 20 | 20 | 30 | 44 | 49 | 49 | 36 |
| 300m | 18 | 18 | 18 | 27 | 40 | 44 | 44 | 31 |
| Valley | 18 | 19 | 19 | 28 | 40 | 45 | 46 | 30 |
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
0°
|
0°
|
1°
|
0°
|
1°
|
0°
|
1°
|
3°
|
| 600m |
2°
|
2°
|
3°
|
3°
|
3°
|
2°
|
4°
|
5°
|
| 300m |
4°
|
4°
|
5°
|
5°
|
6°
|
5°
|
6°
|
7°
|
| Valley |
5°
|
6°
|
6°
|
6°
|
7°
|
6°
|
7°
|
9°
|
| Freezing Level |
800m
|
1,000m
|
1,000m
|
1,000m
|
1,000m
|
1,200m
|
1,600m
|
1,500m
|
| Time | 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|---|---|
| 900m |
-7°
|
-6°
|
-6°
|
-7°
|
-8°
|
-9°
|
-8°
|
-4°
|
| 600m |
-3°
|
-2°
|
-2°
|
-3°
|
-4°
|
-5°
|
-4°
|
0°
|
| 300m |
1°
|
1°
|
1°
|
1°
|
0°
|
-1°
|
0°
|
4°
|
| Valley |
2°
|
2°
|
2°
|
2°
|
2°
|
1°
|
2°
|
5°
|
Additional weather information
Meteorologist's view
A window of fair conditions at first but note the quick deterioration in the afternoon. A severe wind chill developing with walking becoming very difficult or possibly dangerous on higher slopes and ridges in the severe gales or storm force winds.
Weather
Clear spells and a few showers in the early hours, wintry above 600m. A mainly dry morning with some bright spells then rain will spread northeast from early afternoon, heavy at times with severe gale or storm force winds. There will be a couple of hours of sleet or snow above 600m, before turning to rain at all levels by evening. Heavy showers following in the evening, perhaps thundery.
Chance of cloud-free hill tops
70%, becoming 10% during the afternoon.
Low cloud and visibility
Patchy cloud above 500m at first, this lifting in the morning with mostly good visibility for a few hours. However, conditions deteriorate rapidly in the afternoon with extensive cloud developing giving poor visibility above 500m.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
A mixture of clear or bright intervals and rain showers, heavy at times with a small chance of thunder.
Chance of cloud-free hill tops
30%.
Maximum wind speed expected
Southwest 20-30mph gusts 40mph.
Temperature
- At 800m Plus 1C to 3C.
- Valley Plus 7 to 9C.
- Freezing level Above summits.
Low cloud and visibility
Areas of cloud with bases 500 to 700m giving periods of very poor visibility. Good visibility on lower slopes but occasionally few km in showers.
Mountain weather information
Sun 7 Dec
A band of rain is expected to move east in the morning accompanied by strong winds. Drier and brighter conditions following. Freezing level above summits, falling to 1000m in afternoon.
Mon 8 Dec
This is likely to be a mostly bright day with possibly a few sharp showers. Strong to gale force southerly winds on the tops. Wet, stormy conditions perhaps arriving in evening. Freezing level 1000m rising above summits.
Tue 9 Dec
A lot of uncertainty by this stage but a spell of wet and very windy conditions is likely followed by brighter weather from the southwest. Mild with 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.