Mountain weather
Eryri / Snowdonia
Confidence
High for overall evolution, moderate for location of heaviest bursts on rain, and thunderstorms, Wednesday.
-
This eveningSunrise:Sunset:
-
Wed 23 SepSunrise:Sunset:
-
Thu 24 SepSunrise:Sunset:
-
Further outlook
This evening forecast
Turning cloudy through this evening with the potential for an isolated shower.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Heavy Persistent Snow
Poor Visibility
Thunderstorms
Heavy Persistent Rain
Strong Sunlight
Mountain weather forecast
Cloud and rain clearing to drier and brighter weather.
|
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%
|
80%
|
60%
|
10%
|
10%
|
10%
|
10%
|
Wind direction and speed
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | E 6mph knots
E
6mph |
E 8mph knots
E
8mph |
SE 14mph knots
SE
14mph |
S 19mph knots
S
19mph |
S 20mph knots
S
20mph |
SW 21mph knots
SW
21mph |
SW 22mph knots
SW
22mph |
SW 22mph knots
SW
22mph |
|
600m
|
600m | E 4mph knots
E
4mph |
E 6mph knots
E
6mph |
SE 9mph knots
SE
9mph |
S 11mph knots
S
11mph |
S 18mph knots
S
18mph |
SW 18mph knots
SW
18mph |
SW 16mph knots
SW
16mph |
SW 16mph knots
SW
16mph |
|
300m
|
300m | E 3mph knots
E
3mph |
SE 4mph knots
SE
4mph |
SE 5mph knots
SE
5mph |
SE 7mph knots
SE
7mph |
S 15mph knots
S
15mph |
SW 16mph knots
SW
16mph |
SW 14mph knots
SW
14mph |
SW 13mph knots
SW
13mph |
|
Valley
|
Valley | SE 3mph knots
SE
3mph |
SE 5mph knots
SE
5mph |
SE 7mph knots
SE
7mph |
S 7mph knots
S
7mph |
S 12mph knots
S
12mph |
S 14mph knots
S
14mph |
S 10mph knots
S
10mph |
S 10mph knots
S
10mph |
Wind gust
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 8mph | 11mph | 17mph | 25mph | 31mph | 35mph | 33mph | 33mph |
|
600m
|
600m | 6mph | 9mph | 14mph | 18mph | 29mph | 31mph | 27mph | 27mph |
|
300m
|
300m | 5mph | 8mph | 11mph | 13mph | 26mph | 31mph | 25mph | 24mph |
|
Valley
|
Valley | 5mph | 9mph | 13mph | 14mph | 22mph | 25mph | 19mph | 18mph |
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C | 7 degrees Celsius 7°C | 10 degrees Celsius 10°C | 10 degrees Celsius 10°C | 9 degrees Celsius 9°C | 9 degrees Celsius 9°C |
|
600m
|
600m | 6 degrees Celsius 6°C | 6 degrees Celsius 6°C | 6 degrees Celsius 6°C | 10 degrees Celsius 10°C | 12 degrees Celsius 12°C | 13 degrees Celsius 13°C | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C |
|
300m
|
300m | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 12 degrees Celsius 12°C | 14 degrees Celsius 14°C | 15 degrees Celsius 15°C | 14 degrees Celsius 14°C | 13 degrees Celsius 13°C |
|
Valley
|
Valley | 10 degrees Celsius 10°C | 9 degrees Celsius 9°C | 10 degrees Celsius 10°C | 13 degrees Celsius 13°C | 16 degrees Celsius 16°C | 17 degrees Celsius 17°C | 15 degrees Celsius 15°C | 15 degrees Celsius 15°C |
| Freezing Level | Freezing Level |
1500m
|
1500m
|
1600m
|
1800m
|
2300m
|
2500m
|
2700m
|
2800m
|
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 2 degrees Celsius 2°C | 2 degrees Celsius 2°C | 1 degrees Celsius 1°C | 4 degrees Celsius 4°C | 6 degrees Celsius 6°C | 7 degrees Celsius 7°C | 5 degrees Celsius 5°C | 5 degrees Celsius 5°C |
|
600m
|
600m | 5 degrees Celsius 5°C | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C | 8 degrees Celsius 8°C | 9 degrees Celsius 9°C | 10 degrees Celsius 10°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C |
|
300m
|
300m | 8 degrees Celsius 8°C | 7 degrees Celsius 7°C | 6 degrees Celsius 6°C | 10 degrees Celsius 10°C | 12 degrees Celsius 12°C | 12 degrees Celsius 12°C | 11 degrees Celsius 11°C | 11 degrees Celsius 11°C |
|
Valley
|
Valley | 9 degrees Celsius 9°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 12 degrees Celsius 12°C | 14 degrees Celsius 14°C | 14 degrees Celsius 14°C | 14 degrees Celsius 14°C | 13 degrees Celsius 13°C |
| Freezing Level | Freezing Level |
1500m
|
1500m
|
1600m
|
1800m
|
2300m
|
2500m
|
2700m
|
2800m
|
Additional weather information
Meteorologist's view
Wet initially through the morning in the national park, making surfaces underfoot potentially slippery. Low cloud will also lead to poor visibilities on the highest routes. Through the afternoon conditions will turn much better within the park, however UV is still expected to be moderate to high so sun protection is advised.
Weather
Cloud building from the northwest overnight with extensive hill fog developing towards dawn, this will be accompanied by heavy rain with the odd rumble of thunder possible and a low risk of hail. This will clear to the southeast through the morning allowing skies to turn brighter with lengthy sunny periods developing.
Chance of cloud-free hill tops
10% gradually rising to >95% by the afternoon.
Low cloud and visibility
Cloud bases initially lowering to 500-600 m around dawn. Through the morning cloud is expected to clear southward with any cloud then above summits. Moderate visibility initially becoming low or very low in hill fog and heavy rain. Visibilities becoming very good or excellent through the afternoon with views of distant peaks possible.
Ground conditions
No recent ground conditions report available.
Mountain weather information
Weather
A chilly but dry start to the day, variable cloud is expected throughout with bright and sunny spells likely. Cloud and some patchy rain likely arriving from the northwest through the evening.
Chance of cloud-free hill tops
>95% reducing to 60% through the evening.
Maximum wind speed expected
Southerly 25-30 mph.
Temperature
- At 800m Plus 4 Celsius rising to plus 9 Celsius.
- Valley Plus 11 Celsius rising to plus 17 Celsius.
- Freezing level Above summits.
Low cloud and visibility
No low cloud expected with all cloud above summits, very good or excellent visibilities expected with views of distant peaks possible. Low cloud arriving after dusk leading to a risk of moderate or poor visibilities.
Ground conditions
No recent ground conditions report available.
Mountain weather information
Fri 25 Sep
Turning more unsettled with rain at times. Moderate to fresh southwesterly winds
Sat 26 Sep
Drier and brighter Saturday with the chance of the odd shower.
Sun 27 Sep
Dry and bright initially with cloud arriving through the afternoon and the chance of rain through the evening.
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.