Mountain weather
Eryri / Snowdonia Mountain weather forecast table
Confidence
High for a relatively benign period, with plenty of drier conditions, but only moderate confidence for the extent of cloud on Tuesday. Confidence increasing for mainly fine weather Wednesday and Thursday, and less humid. Low confidence for any details Friday onward.
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.
Strong Sunlight
Harmful UV levels from sunlight increase with altitude giving a greater risk of sunburn and eye damage, even on some overcast days. On breezy days, the cooling effect of wind on exposed skin may disguise any feeling of sunburn until it is too late. If there is snow cover, glare increases the effect of UV rays especially on the eyes. It is advisable to wear sun block, protective clothing such as a long-sleeved top and hat and have good quality eye protection.
Mountain weather forecast
Rather cloudy, with some drizzle or showers. Still rather humid.
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
Weather (at 800m) |
|
|
|
|
|
|
Chance of precipitation (at 800m) |
50% | 60% | 70% | 50% | 30% | 20% |
Wind direction and speed (mph)
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
S
8
|
W
6
|
NW
7
|
N
11
|
N
14
|
N
20
|
| 600m |
S
8
|
W
6
|
NW
9
|
NW
10
|
N
10
|
N
9
|
| 300m |
S
4
|
NW
4
|
NW
6
|
N
7
|
N
8
|
N
5
|
| Valley |
S
4
|
N
5
|
NW
6
|
N
8
|
N
8
|
N
6
|
Wind gust (mph)
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m | 9 | 8 | 10 | 16 | 18 | 24 |
| 600m | 9 | 8 | 12 | 14 | 13 | 13 |
| 300m | 7 | 6 | 8 | 12 | 12 | 13 |
| Valley | 7 | 6 | 8 | 12 | 12 | 14 |
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
12°
|
12°
|
12°
|
11°
|
9°
|
8°
|
| 600m |
14°
|
14°
|
13°
|
12°
|
11°
|
10°
|
| 300m |
15°
|
15°
|
15°
|
14°
|
13°
|
12°
|
| Valley |
16°
|
15°
|
15°
|
14°
|
14°
|
13°
|
| Freezing Level |
3,000m
|
2,800m
|
2,600m
|
2,400m
|
2,200m
|
2,100m
|
Altitude above mean sea level
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
11°
|
12°
|
11°
|
8°
|
6°
|
4°
|
| 600m |
13°
|
13°
|
12°
|
10°
|
9°
|
8°
|
| 300m |
16°
|
15°
|
14°
|
13°
|
12°
|
11°
|
| Valley |
16°
|
15°
|
14°
|
13°
|
13°
|
12°
|
Additional weather information
Meteorologist's view
Any brighter spells will allow temperatures to reach 22 Celsius in the east, during which it will feel rather humid. Sunny spells will also bring a low chance of High UV, with appropriate sun protection required
Weather
Rather cloudy, with many hills shrouded, along with some outbreaks of drizzle. Cloud will break at times to allow some sunny spells, but perhaps also a heavier, thundery shower or two developing, especially in afternoon towards Llanthony Priory and Hay Bluff. Any brighter intervals will lead to a rather humid and warm feel, with only light winds.
Chance of cloud-free hill tops
20% at first, improving to 70% during the afternoon, with best chances in the southeast. Improving to near 100% by dark.
Low cloud and visibility
Most hills and routes above 500m will be shrouded during the morning, with scattered bases around 300m in the west. This will gradually lift and break to become more scattered at around 800m, with just a few patches lingering down to 600m. Cloud clearing after dark. Good visibility at times, but will become poor to very poor in drizzle and rain and any heavy showers.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Largely dry and sunny, but feeling fresher than recent days given lower humidity and light northerly winds. Some fair weather cloud perhaps developing, but staying above summits.
Chance of cloud-free hill tops
Greater than 95%.
Maximum wind speed expected
Northerly 20-30mph across summits.
Temperature
- At 800m Plus 7 Celsius rising to Plus 11 Celsius.
- Valley Plus 8 Celsius rising to Plus 19 Celsius.
- Freezing level Above summits.
Low cloud and visibility
Very good to Excellent visibility of distant hills, with summits free of cloud.
Mountain weather information
Thu 3 Jul
Sunrise:
Sunset:
A similar day to Wednesday, but perhaps a little more cloud which could allow for a few showers to develop. Otherwise fine with sunny spells and light winds.
Fri 4 Jul
Sunrise:
Sunset:
Winds likely strengthening through the day, with cloud also increasing ahead of rain moving through. This most likely later in the day, however the timing and extent of rainfall is currently low confidence.
Sat 5 Jul
Sunrise:
Sunset:
A rather cloudy and breezy day, with occasional showers, perhaps merging to give some more persistent rain. Best of any brighter intervals in the east.
Updated at:
Summit specific forecast
Mountain summit forecast map
Loading map…
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.