Mountain weather
Eryri / Snowdonia
Confidence
High for over unsettled nature of the weather, but lower for rain and low cloud details for Saturday.
-
Sat 16 MaySunrise:Sunset:
-
Sun 17 MaySunrise:Sunset:
-
Further outlook
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Severe Chill Effect
Poor Visibility
Heavy Persistent Rain
Mountain weather forecast
Cloudy with outbreaks of rain, these turning heavy at times.
|
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 |
20%
|
60%
|
80%
|
60%
|
90%
|
40%
|
Wind direction and speed
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
900m
|
900m | SW 14mph knots
SW
14mph |
SW 14mph knots
SW
14mph |
SW 16mph knots
SW
16mph |
SW 18mph knots
SW
18mph |
W 20mph knots
W
20mph |
W 20mph knots
W
20mph |
|
600m
|
600m | S 10mph knots
S
10mph |
SW 11mph knots
SW
11mph |
SW 14mph knots
SW
14mph |
SW 14mph knots
SW
14mph |
SW 12mph knots
SW
12mph |
W 11mph knots
W
11mph |
|
300m
|
300m | S 5mph knots
S
5mph |
SW 7mph knots
SW
7mph |
SW 10mph knots
SW
10mph |
SW 10mph knots
SW
10mph |
SW 7mph knots
SW
7mph |
W 7mph knots
W
7mph |
|
Valley
|
Valley | S 5mph knots
S
5mph |
SW 7mph knots
SW
7mph |
SW 9mph knots
SW
9mph |
W 9mph knots
W
9mph |
SW 7mph knots
SW
7mph |
W 7mph knots
W
7mph |
Wind gust
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
900m
|
900m | 16mph | 17mph | 21mph | 24mph | 24mph | 24mph |
|
600m
|
600m | 13mph | 15mph | 18mph | 19mph | 16mph | 15mph |
|
300m
|
300m | 10mph | 12mph | 15mph | 17mph | 13mph | 14mph |
|
Valley
|
Valley | 10mph | 12mph | 14mph | 15mph | 13mph | 15mph |
|
Time
|
Time |
06:00
|
09:00
|
12:00
|
15:00
|
18:00
|
21:00
|
|---|---|---|---|---|---|---|---|
|
900m
|
900m | 2 degrees Celsius 2°C | 2 degrees Celsius 2°C | 4 degrees Celsius 4°C | 5 degrees Celsius 5°C | 4 degrees Celsius 4°C | 4 degrees Celsius 4°C |
|
600m
|
600m | 4 degrees Celsius 4°C | 5 degrees Celsius 5°C | 6 degrees Celsius 6°C | 7 degrees Celsius 7°C | 6 degrees Celsius 6°C | 6 degrees Celsius 6°C |
|
300m
|
300m | 7 degrees Celsius 7°C | 8 degrees Celsius 8°C | 8 degrees Celsius 8°C | 9 degrees Celsius 9°C | 9 degrees Celsius 9°C | 8 degrees Celsius 8°C |
|
Valley
|
Valley | 8 degrees Celsius 8°C | 9 degrees Celsius 9°C | 10 degrees Celsius 10°C | 11 degrees Celsius 11°C | 10 degrees Celsius 10°C | 9 degrees Celsius 9°C |
| Freezing Level | Freezing Level |
1100m
|
1300m
|
1600m
|
1600m
|
1500m
|
1400m
|
|
Time
|
Time |
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 | 0 degrees Celsius 0°C | -1 degrees Celsius -1°C | -2 degrees Celsius -2°C |
|
600m
|
600m | 1 degrees Celsius 1°C | 1 degrees Celsius 1°C | 2 degrees Celsius 2°C | 3 degrees Celsius 3°C | 3 degrees Celsius 3°C | 2 degrees Celsius 2°C |
|
300m
|
300m | 5 degrees Celsius 5°C | 5 degrees Celsius 5°C | 6 degrees Celsius 6°C | 7 degrees Celsius 7°C | 7 degrees Celsius 7°C | 6 degrees Celsius 6°C |
|
Valley
|
Valley | 6 degrees Celsius 6°C | 7 degrees Celsius 7°C | 8 degrees Celsius 8°C | 9 degrees Celsius 9°C | 9 degrees Celsius 9°C | 8 degrees Celsius 8°C |
| Freezing Level | Freezing Level |
1100m
|
1300m
|
1600m
|
1600m
|
1500m
|
1400m
|
Additional weather information
Meteorologist's view
Rainfall combined with low cloud are expected to reduce visibility on exposed terrain, with saturated surfaces increasing the risk of slips and difficult footing.
Weather
Largely dry but cloudy start, but outbreaks of light rain will arrive from the west by mid-morning and then become heavy at times. This evening the rain moves away east, with largely cloudy conditions and isolated showers following.
Chance of cloud-free hill tops
60% until midday, then decreasing to 10%. Improving 80% this evening.
Low cloud and visibility
Cloud base dropping by midday to around 700-800m, with occasional patches of cloud possible 600-700m. Good visibility to start but becoming hazy to poor in low cloud and rain.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Generally cloudy, with only limited cloud breaks, and isolated showers until mid-afternoon. Then showers become frequent and often heavy, with a chance of thunder, especially through the evening.
Chance of cloud-free hill tops
80% lowering to 40% from mid-afternoon.
Maximum wind speed expected
Westerly 30-35 mph with gusts to 45 mph.
Temperature
- At 800m Plus 3 Celsius rising to plus 6 Celsius.
- Valley Plus 4 Celsius rising to plus 14 Celsius.
- Freezing level Above summits.
Low cloud and visibility
Occasional low cloud covering summits with heavy showers, bases around 600-700m. Visibility generally very good with distance hills visible, but dropping to poor in low cloud and showers.
Ground conditions
No recent ground conditions report available.
Mountain weather information
Mon 18 May
Scattered showers followed by evening heavy rain. Breezy southwesterly winds.
Tue 19 May
Heavy showers or longer spells of rain. Strong southwesterly winds, risk of summit gales.
Wed 20 May
Heavy showers or longer spells of rain. Strong southwesterly winds, risk of summit gales.
Mountain weather information
Mon 18 May
Scattered showers followed by evening heavy rain. Breezy southwesterly winds.
Tue 19 May
Heavy showers or longer spells of rain. Strong southwesterly winds, risk of summit gales.
Wed 20 May
Heavy showers or longer spells of rain. Strong southwesterly winds, risk of summit gales.
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.