Mountain weather
Eryri / Snowdonia
Confidence
High for a generally dry weekend. Moderate for cloud/hill fog details on Monday.
-
Sat 19 SepSunrise:Sunset:
-
Sun 20 SepSunrise:Sunset:
-
Further outlook
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Poor Visibility
Strong Sunlight
Mountain weather forecast
Windy with bright or sunny spells and a low chance of a brief blustery shower.
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
Weather
(at 800m)
|
Weather symbols | ||||||
|
Chance of
precipitation (at 800m)
|
Chance of precipitation |
30%
|
10%
|
10%
|
10%
|
10%
|
10%
|
Wind direction and speed
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
900m
|
900m | SW 41mph knots
SW
41mph |
W 36mph knots
W
36mph |
W 32mph knots
W
32mph |
W 31mph knots
W
31mph |
W 31mph knots
W
31mph |
W 30mph knots
W
30mph |
|
600m
|
600m | SW 28mph knots
SW
28mph |
W 26mph knots
W
26mph |
W 25mph knots
W
25mph |
W 24mph knots
W
24mph |
SW 19mph knots
SW
19mph |
W 18mph knots
W
18mph |
|
300m
|
300m | SW 17mph knots
SW
17mph |
W 17mph knots
W
17mph |
W 18mph knots
W
18mph |
W 17mph knots
W
17mph |
SW 12mph knots
SW
12mph |
W 12mph knots
W
12mph |
|
Valley
|
Valley | SW 17mph knots
SW
17mph |
W 17mph knots
W
17mph |
W 18mph knots
W
18mph |
W 17mph knots
W
17mph |
SW 12mph knots
SW
12mph |
W 11mph knots
W
11mph |
Wind gust
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
900m
|
900m | 48mph | 43mph | 40mph | 39mph | 38mph | 36mph |
|
600m
|
600m | 34mph | 33mph | 33mph | 31mph | 25mph | 25mph |
|
300m
|
300m | 30mph | 29mph | 30mph | 28mph | 23mph | 24mph |
|
Valley
|
Valley | 30mph | 29mph | 30mph | 28mph | 23mph | 23mph |
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
900m
|
900m | 11 degrees Celsius 11°C | 9 degrees Celsius 9°C | 9 degrees Celsius 9°C | 9 degrees Celsius 9°C | 9 degrees Celsius 9°C | 8 degrees Celsius 8°C |
|
600m
|
600m | 13 degrees Celsius 13°C | 12 degrees Celsius 12°C | 12 degrees Celsius 12°C | 12 degrees Celsius 12°C | 12 degrees Celsius 12°C | 11 degrees Celsius 11°C |
|
300m
|
300m | 15 degrees Celsius 15°C | 14 degrees Celsius 14°C | 14 degrees Celsius 14°C | 15 degrees Celsius 15°C | 14 degrees Celsius 14°C | 13 degrees Celsius 13°C |
|
Valley
|
Valley | 16 degrees Celsius 16°C | 16 degrees Celsius 16°C | 16 degrees Celsius 16°C | 16 degrees Celsius 16°C | 16 degrees Celsius 16°C | 14 degrees Celsius 14°C |
| Freezing Level | Freezing Level |
2200m
|
1800m
|
1900m
|
2000m
|
2000m
|
1800m
|
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
900m
|
900m | 6 degrees Celsius 6°C | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C | 3 degrees Celsius 3°C |
|
600m
|
600m | 8 degrees Celsius 8°C | 7 degrees Celsius 7°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 7 degrees Celsius 7°C |
|
300m
|
300m | 12 degrees Celsius 12°C | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C | 12 degrees Celsius 12°C | 12 degrees Celsius 12°C | 11 degrees Celsius 11°C |
|
Valley
|
Valley | 13 degrees Celsius 13°C | 13 degrees Celsius 13°C | 13 degrees Celsius 13°C | 13 degrees Celsius 13°C | 14 degrees Celsius 14°C | 12 degrees Celsius 12°C |
| Freezing Level | Freezing Level |
2200m
|
1800m
|
1900m
|
2000m
|
2000m
|
1800m
|
Additional weather information
Meteorologist's view
Winds may gust to 40-45 mph over the highest summits first thing leading to considerable buffeting and difficult walking conditions. Winds easing thereafter through the day.
Weather
Early low cloud, mist and fog will gradually clear to leave a largely dry day with sunny spells, but an isolated brief passing shower can't be entirely ruled out.
Chance of cloud-free hill tops
60% becoming 80%.
Low cloud and visibility
Periods of cloud above 700-800m first thing, mainly in the west. Becoming patches above 900m by the afternoon with most summits clearing of cloud. Often poor or very poor visibility in cloud, but otherwise very good with excellent air clarity.
Ground conditions
No recent ground conditions report available.
Mountain weather information
Weather
A fine day with a mixture of cloud and sunny periods, these prolonged at times. Much lighter winds.
Chance of cloud-free hill tops
70%
Maximum wind speed expected
Westerly 15-20 mph gusting 30 mph, easing through the day.
Temperature
- At 800m Plus 6 Celsius rising to plus 10 Celsius.
- Valley Plus 8 Celsius rising to plus 18 Celsius.
- Freezing level Above the summits.
Low cloud and visibility
Patches above 800-900m through the morning but generally clearing by the afternoon. Very good visibility with excellent air clarity. Locally poor/very poor visibility in cloud.
Ground conditions
No recent ground conditions report available.
Mountain weather information
Mon 21 Sep
A cloudier day with occasional brighter intervals, mainly in the east. The cloud may be sufficiently thick enough to give some drizzle in the west. Prolonged periods of hill fog. Moderate southwesterly winds.
Tue 22 Sep
Probably dry with the cloud breaking up more readily to give some sunny spells. Light to moderate southwesterly winds.
Wed 23 Sep
A more changeable day with some rain possible at times, this most likely in the morning. Light to moderate northerly winds.
Mountain weather information
Mon 21 Sep
A cloudier day with occasional brighter intervals, mainly in the east. The cloud may be sufficiently thick enough to give some drizzle in the west. Prolonged periods of hill fog. Moderate southwesterly winds.
Tue 22 Sep
Probably dry with the cloud breaking up more readily to give some sunny spells. Light to moderate southwesterly winds.
Wed 23 Sep
A more changeable day with some rain possible at times, this most likely in the morning. Light to moderate northerly winds.
Summit specific forecast
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.