Mountain weather
Eryri / Snowdonia
Confidence
High for over unsettled nature of the weather, but lower for rate and intensity of showers.
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This eveningSunrise:Sunset:
-
Sun 17 MaySunrise:Sunset:
-
Mon 18 MaySunrise:Sunset:
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Further outlook
This evening forecast
Showers easing then clear spells into the night.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Strong Sunlight
Poor Visibility
Thunderstorms
Mountain weather forecast
Sunny spells with showers by the afternoon.
|
Time
|
Time |
00:00
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03:00
|
06:00
|
09:00
|
12:00
|
15:00
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18:00
|
21:00
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|---|---|---|---|---|---|---|---|---|---|
|
Weather
(at 800m)
|
Weather symbols | ||||||||
|
Chance of
precipitation (at 800m)
|
Chance of precipitation |
<5%
|
10%
|
10%
|
20%
|
60%
|
60%
|
60%
|
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 | W 23mph knots
W
23mph |
W 23mph knots
W
23mph |
W 22mph knots
W
22mph |
W 20mph knots
W
20mph |
SW 22mph knots
SW
22mph |
SW 29mph knots
SW
29mph |
SW 26mph knots
SW
26mph |
SW 24mph knots
SW
24mph |
|
600m
|
600m | W 13mph knots
W
13mph |
W 12mph knots
W
12mph |
W 14mph knots
W
14mph |
W 16mph knots
W
16mph |
SW 18mph knots
SW
18mph |
SW 22mph knots
SW
22mph |
SW 18mph knots
SW
18mph |
SW 15mph knots
SW
15mph |
|
300m
|
300m | W 8mph knots
W
8mph |
W 7mph knots
W
7mph |
W 9mph knots
W
9mph |
W 11mph knots
W
11mph |
SW 12mph knots
SW
12mph |
SW 15mph knots
SW
15mph |
SW 12mph knots
SW
12mph |
SW 9mph knots
SW
9mph |
|
Valley
|
Valley | W 8mph knots
W
8mph |
W 7mph knots
W
7mph |
W 9mph knots
W
9mph |
W 11mph knots
W
11mph |
SW 12mph knots
SW
12mph |
SW 15mph knots
SW
15mph |
SW 12mph knots
SW
12mph |
SW 9mph knots
SW
9mph |
Wind gust
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 28mph | 27mph | 26mph | 26mph | 29mph | 36mph | 32mph | 29mph |
|
600m
|
600m | 17mph | 17mph | 17mph | 21mph | 24mph | 28mph | 23mph | 20mph |
|
300m
|
300m | 16mph | 15mph | 16mph | 19mph | 21mph | 25mph | 21mph | 17mph |
|
Valley
|
Valley | 16mph | 15mph | 16mph | 19mph | 20mph | 25mph | 20mph | 17mph |
|
Time
|
Time |
00:00
|
03:00
|
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|---|---|
|
900m
|
900m | 3 degrees Celsius 3°C | 2 degrees Celsius 2°C | 1 degrees Celsius 1°C | 1 degrees Celsius 1°C | 3 degrees Celsius 3°C | 3 degrees Celsius 3°C | 3 degrees Celsius 3°C | 2 degrees Celsius 2°C |
|
600m
|
600m | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C | 6 degrees Celsius 6°C | 5 degrees Celsius 5°C | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C |
|
300m
|
300m | 7 degrees Celsius 7°C | 6 degrees Celsius 6°C | 6 degrees Celsius 6°C | 7 degrees Celsius 7°C | 9 degrees Celsius 9°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 7 degrees Celsius 7°C |
|
Valley
|
Valley | 9 degrees Celsius 9°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 9 degrees Celsius 9°C | 10 degrees Celsius 10°C | 10 degrees Celsius 10°C | 9 degrees Celsius 9°C | 8 degrees Celsius 8°C |
| Freezing Level | Freezing Level |
1200m
|
1100m
|
1000m
|
1000m
|
1200m
|
1300m
|
1200m
|
1200m
|
|
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 | -5 degrees Celsius -5°C | -5 degrees Celsius -5°C | -5 degrees Celsius -5°C | -3 degrees Celsius -3°C | -4 degrees Celsius -4°C | -4 degrees Celsius -4°C | -4 degrees Celsius -4°C |
|
600m
|
600m | 1 degrees Celsius 1°C | 0 degrees Celsius 0°C | -1 degrees Celsius -1°C | -1 degrees Celsius -1°C | 1 degrees Celsius 1°C | 0 degrees Celsius 0°C | 0 degrees Celsius 0°C | 0 degrees Celsius 0°C |
|
300m
|
300m | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C | 6 degrees Celsius 6°C | 5 degrees Celsius 5°C | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C |
|
Valley
|
Valley | 7 degrees Celsius 7°C | 5 degrees Celsius 5°C | 5 degrees Celsius 5°C | 6 degrees Celsius 6°C | 8 degrees Celsius 8°C | 7 degrees Celsius 7°C | 7 degrees Celsius 7°C | 6 degrees Celsius 6°C |
| Freezing Level | Freezing Level |
1200m
|
1100m
|
1000m
|
1000m
|
1200m
|
1300m
|
1200m
|
1200m
|
Additional weather information
Meteorologist's view
Damp underfoot given recent rainfall, with rain jackets advised due to the risk of heavy showers. UV levels moderate with sun protection needed.
Weather
Generally cloudy especially in the south and west with only limited cloud breaks, and isolated showers until mid-afternoon. Then showers become more widespread and sometimes heavy, with a small chance of thunder. Showers becoming more organised from late evening and into the night with heavy downpours.
Chance of cloud-free hill tops
50% rising to 70%.
Low cloud and visibility
Patchy low cloud covering summits with heavy showers, bases around 500-700m and to start the morning. Visibility generally very good with distance hills visible, but dropping to poor in low cloud and showers.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
A band of heavy, organised showers clearing eastwards during the early hours. Mostly dry thereafter with a low risk of a few showers into the afternoon. More persistent rain edging in by the evening and moving across the park into the night, heavy in the west. Winds increasing.
Chance of cloud-free hill tops
60% dropping to 40% by end of day.
Maximum wind speed expected
Southwesterly 15-20 mph, becoming southerly 30-35 mph by the evening.
Temperature
- At 800m Plus 5 Celsius rising to plus 8 Celsius.
- Valley Plus 7 Celsius rising to plus 14 Celsius.
- Freezing level Above summits.
Low cloud and visibility
Broken cloud around 400-500 m at first, lifting mostly above summits, then lowering further by the evening down to 400m and becoming more widespread across the park. Good visibility outside showers, dropping to very poor by the evening in more persistent rain.
Ground conditions
No recent ground conditions report available.
Mountain weather information
Tue 19 May
Rain clearing through the morning followed by sunshine and showers. Strong southwesterly winds, risk of summit gales.
Wed 20 May
Further showers possible but detail uncertain. Temperatures rising. Strong southwesterly winds.
Thu 21 May
Early fog clearing then a fine day with plenty of sunshine. Warmer with moderate southerly 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.