Mountain weather
Eryri / Snowdonia Mountain weather forecast table
Confidence
High for a cooler and more unsettled period but low for the clearance of the rain and the distribution/intensity of any showers over the following days.
This evening forecast
Cloudy to overcast with prolonged rain, heavy at times. Rain perhaps becoming lighter by midnight.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Poor Visibility
Poor visibility presents challenging route finding conditions. Visibility could be significantly less than 50 metres in all directions with few or no visual references, especially on featureless moors or plateaux. Distances become hard to judge and cliff or cornice edges can be difficult to recognise. These conditions require good navigational skills. There is a risk of white-out conditions when mist or fog is combined with extensive snow cover.
Thunderstorms
Lightning is a significant mountain hazard which can result in serious injury or death. Mountain terrain often leaves one highly exposed to lightning strikes. Hail may give unpleasant conditions with torrential rain and localised flash flooding also possible, mainly in Summer months.
Mountain weather forecast
Some residual rain overnight, slowly clearing northeast. Some sunny spells and a few showers breaking out in the afternoon.
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
Weather (at 800m) |
|
|
|
|
|
|
|
|
Chance of precipitation (at 800m) |
90% | 60% | 20% | 20% | 30% | 40% | 30% | 20% |
Wind direction and speed (mph)
Altitude above mean sea level
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
| 900m |
SE
18
|
SE
15
|
SE
16
|
SE
20
|
SE
21
|
SE
23
|
SE
23
|
SE
25
|
| 600m |
S
11
|
SE
12
|
SE
12
|
SE
16
|
SE
17
|
SE
18
|
SE
18
|
SE
18
|
| 300m |
S
7
|
SE
6
|
SE
5
|
SE
11
|
SE
14
|
SE
14
|
SE
13
|
SE
12
|
| Valley |
S
7
|
SE
6
|
SE
6
|
SE
11
|
SE
13
|
SE
14
|
SE
13
|
SE
12
|
Wind gust (mph)
Altitude above mean sea level
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
| 900m | 22 | 19 | 20 | 26 | 29 | 31 | 30 | 32 |
| 600m | 15 | 16 | 16 | 22 | 24 | 25 | 25 | 25 |
| 300m | 12 | 11 | 11 | 19 | 23 | 24 | 23 | 22 |
| Valley | 12 | 12 | 12 | 18 | 22 | 24 | 23 | 22 |
Altitude above mean sea level
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
| 900m |
9°
|
8°
|
7°
|
8°
|
9°
|
10°
|
9°
|
8°
|
| 600m |
10°
|
9°
|
10°
|
10°
|
12°
|
12°
|
12°
|
10°
|
| 300m |
12°
|
11°
|
12°
|
13°
|
14°
|
15°
|
15°
|
12°
|
| Valley |
12°
|
12°
|
13°
|
14°
|
16°
|
16°
|
16°
|
14°
|
| Freezing Level |
2,400m
|
2,300m
|
1,900m
|
1,800m
|
2,000m
|
2,100m
|
2,000m
|
2,000m
|
Altitude above mean sea level
| 00:00 | 03:00 | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 | |
|---|---|---|---|---|---|---|---|---|
| 900m |
5°
|
4°
|
4°
|
3°
|
5°
|
6°
|
5°
|
3°
|
| 600m |
8°
|
7°
|
7°
|
7°
|
8°
|
9°
|
9°
|
7°
|
| 300m |
10°
|
10°
|
11°
|
11°
|
12°
|
12°
|
12°
|
10°
|
| Valley |
11°
|
11°
|
12°
|
12°
|
13°
|
14°
|
14°
|
12°
|
Additional weather information
Meteorologist's view
Perhaps drier in the north of the Park, the showers being mostly confined to the south.
Weather
The evening rain will become light and patchy before clearing north-eastwards later in the night. A bright and dry morning will follow, with patches of low cloud slowly lifting into scattered showers during the afternoon. These will be mostly light but the odd heavy one cannot be ruled out.
Chance of cloud-free hill tops
Generally 60-70% in the morning but 80-90% in the afternoon.
Low cloud and visibility
Very good but locally poor in any low cloud, with bases as low as 400m. Cloud base slowly lifting to 900m during the morning, with good panoramic views all around, although visibility may become moderate in and around any showers, the cloud suddenly dropping to 800m.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Another day with low cloud breaking into sunny spells and thundery showers, heavier and more frequent in the south.
Chance of cloud-free hill tops
Quickly improving from 30% to 95% or more in the morning.
Maximum wind speed expected
East to southeast 20mph with gusts 30mph
Temperature
- At 800m Plus 07 degree Celsius rising to plus 13 Celsius.
- Valley Plus 14 degree Celsius rising to plus 21 Celsius.
- Freezing level Above summits.
Low cloud and visibility
Good to very good but locally poor in any low cloud at first, with bases as low as 400m. Generally excellent in the afternoon but a chance of deterioration in ad around any shower.
Mountain weather information
Thu 16 May
Sunrise:
Sunset:
Some mist and fog patches at first, breaking into sunny spells and thundery showers in the afternoon. Showers likely merging into a longer spell of rain in the evening.
Fri 17 May
Sunrise:
Sunset:
Cloudy with extensive low cloud and patchy drizzle in the morning, the cloud breaking into sunny spells and showers in the afternoon.
Sat 18 May
Sunrise:
Sunset:
Drier and brighter with sunny spells and the odd afternoon shower.
Updated at:
Summit specific forecast
Mountain summit forecast map
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Key
Mountain summits
Other points of interest
Cluster of multiple stations
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.