Mountain weather
Eryri / Snowdonia
Confidence
High for a changeable few days but moderate for extent and timing of early rain on Sunday.
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This eveningSunrise:Sunset:
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Sun 6 SepSunrise:Sunset:
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Mon 7 SepSunrise:Sunset:
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Further outlook
This evening forecast
Turning increasingly cloudy overnight, but remaining dry.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Poor Visibility
Thunderstorms
Strong Sunlight
Mountain weather forecast
Showery rain clearing to bright or sunny spells. Cloudier evening.
|
Time
|
Time |
00:00
|
03:00
|
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 |
20%
|
30%
|
40%
|
30%
|
30%
|
20%
|
30%
|
60%
|
Wind direction and speed
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | S 24mph knots
S
24mph |
S 27mph knots
S
27mph |
S 30mph knots
S
30mph |
S 34mph knots
S
34mph |
S 39mph knots
S
39mph |
SW 37mph knots
SW
37mph |
SW 35mph knots
SW
35mph |
SW 31mph knots
SW
31mph |
|
600m
|
600m | S 18mph knots
S
18mph |
S 21mph knots
S
21mph |
S 21mph knots
S
21mph |
S 26mph knots
S
26mph |
S 28mph knots
S
28mph |
S 26mph knots
S
26mph |
S 21mph knots
S
21mph |
SW 21mph knots
SW
21mph |
|
300m
|
300m | S 11mph knots
S
11mph |
S 14mph knots
S
14mph |
S 14mph knots
S
14mph |
S 17mph knots
S
17mph |
S 21mph knots
S
21mph |
S 18mph knots
S
18mph |
S 15mph knots
S
15mph |
SW 14mph knots
SW
14mph |
|
Valley
|
Valley | S 11mph knots
S
11mph |
S 14mph knots
S
14mph |
S 13mph knots
S
13mph |
S 17mph knots
S
17mph |
S 20mph knots
S
20mph |
S 17mph knots
S
17mph |
S 14mph knots
S
14mph |
SW 13mph knots
SW
13mph |
Wind gust
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 32mph | 36mph | 36mph | 41mph | 49mph | 48mph | 43mph | 40mph |
|
600m
|
600m | 26mph | 30mph | 29mph | 33mph | 38mph | 36mph | 29mph | 28mph |
|
300m
|
300m | 23mph | 27mph | 26mph | 31mph | 34mph | 32mph | 27mph | 25mph |
|
Valley
|
Valley | 23mph | 28mph | 26mph | 30mph | 32mph | 30mph | 25mph | 24mph |
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 9 degrees Celsius 9°C | 10 degrees Celsius 10°C | 9 degrees Celsius 9°C | 10 degrees Celsius 10°C | 13 degrees Celsius 13°C | 14 degrees Celsius 14°C | 12 degrees Celsius 12°C | 13 degrees Celsius 13°C |
|
600m
|
600m | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C | 13 degrees Celsius 13°C | 15 degrees Celsius 15°C | 16 degrees Celsius 16°C | 14 degrees Celsius 14°C | 14 degrees Celsius 14°C |
|
300m
|
300m | 13 degrees Celsius 13°C | 14 degrees Celsius 14°C | 13 degrees Celsius 13°C | 15 degrees Celsius 15°C | 18 degrees Celsius 18°C | 19 degrees Celsius 19°C | 17 degrees Celsius 17°C | 16 degrees Celsius 16°C |
|
Valley
|
Valley | 15 degrees Celsius 15°C | 15 degrees Celsius 15°C | 14 degrees Celsius 14°C | 16 degrees Celsius 16°C | 20 degrees Celsius 20°C | 20 degrees Celsius 20°C | 18 degrees Celsius 18°C | 17 degrees Celsius 17°C |
| Freezing Level | Freezing Level |
3700m
|
3700m
|
3500m
|
3500m
|
3300m
|
3100m
|
3200m
|
3000m
|
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 5 degrees Celsius 5°C | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C | 6 degrees Celsius 6°C | 7 degrees Celsius 7°C | 8 degrees Celsius 8°C | 7 degrees Celsius 7°C | 8 degrees Celsius 8°C |
|
600m
|
600m | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 9 degrees Celsius 9°C | 10 degrees Celsius 10°C | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C |
|
300m
|
300m | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C | 12 degrees Celsius 12°C | 14 degrees Celsius 14°C | 15 degrees Celsius 15°C | 14 degrees Celsius 14°C | 14 degrees Celsius 14°C |
|
Valley
|
Valley | 13 degrees Celsius 13°C | 12 degrees Celsius 12°C | 12 degrees Celsius 12°C | 13 degrees Celsius 13°C | 15 degrees Celsius 15°C | 16 degrees Celsius 16°C | 16 degrees Celsius 16°C | 16 degrees Celsius 16°C |
| Freezing Level | Freezing Level |
3700m
|
3700m
|
3500m
|
3500m
|
3300m
|
3100m
|
3200m
|
3000m
|
Additional weather information
Meteorologist's view
A fine day for hill walking but remember some extra layers if you are heading to the summits as it will feel quite cool in the breeze on the highest peaks.
Weather
Showery rain is possible for a time from early morning but this is likely to clear by mid-morning. Thereafter another fine day is expected with a mixture of cloud and sunny spells. Cloud increasing from the west during the evening with further outbreaks of rain arriving before midnight.
Chance of cloud-free hill tops
60% rising to 80% from mid-morning before lowering again towards 70% through the evening.
Low cloud and visibility
Many hills and mountain top clear of cloud but patches above 600-700m in association with morning rain. Cloud above 500-700m turning more persistent after dark (low confidence). Poor or very poor visibility in the cloud and occasionally moderate at most levels in the rain. Otherwise often good, albeit somewhat hazier than on Saturday.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Outbreaks of rain will move across the park during the early hours, some heavier bursts are likely. Cloudy during the day with bright or sunny spells developing. A band of squally rain is likely from mid-afternoon, with some heavy and possibly thundery bursts.
Chance of cloud-free hill tops
50% rising to 70% from early-morning, before reducing to 50% later until the evening.
Maximum wind speed expected
Southwesterly 20-25mph, gusting 35-45 mph
Temperature
- At 800m Plus 11 Celsius rising to plus 16 Celsius.
- Valley Plus 12 Celsius rising to plus 20 Celsius.
- Freezing level Well above the summits.
Low cloud and visibility
Cloud bases close to 500 meters during the early hours, but these lifting by mid-morning, leaving most summits cloud free. However cloud bases likely to descend again during the evening. Poor or very poor visibility in the cloud and occasionally moderate at most levels in the rain. Otherwise often good
Ground conditions
No recent ground conditions report available.
Mountain weather information
Tue 8 Sep
Overnight rain may linger into the morning before turning brighter with sunny spells and frequent blustery showers. Feeling cool in the fresh to strong westerly, then northwesterly winds.
Wed 9 Sep
Still breezy but not as windy with moderate northwesterly winds gradually easing. Rather cloudy but mainly dry with sunny spells. Feeling cool.
Thu 10 Sep
Remaining changeable with cloud and rain moving eastwards during the day. Becoming rather breezy. Temperatures near average.
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.