Mountain weather

Mountain weather

Eryri / Snowdonia

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Confidence

High confidence for an unsettled period with heavy rain, possibly thundery in places, followed by showers. Lower for distribution of any thundery downpours.

Mountain hazards

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.
Heavy Persistent Rain
Heavy and persistent rain can lead to drenched clothing and footwear with waterproofs often becoming soaked through, especially if accompanied by strong winds. This can lead to significant loss of body heat and an increased likelihood of hypothermia. Terrain may turn increasingly boggy underfoot while streams can flood and become impassable. There may also be a risk of flooding in valleys or glens. If there is snow cover, a heightened avalanche hazard is possible and avalanche reports should be consulted where available.

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.
Updated: 
Mountain hazards explained

Mountain weather forecast

Persistent rain, mainly heavy before becoming lighter this evening.

Time
 Time
06:00
09:00
12:00
15:00
18:00
21:00
Weather
(at 800m)
 Weather symbols Light rain Heavy Rain Heavy Rain Heavy Rain Light rain Light rain
Chance of
precipitation
(at 800m)
 Chance of precipitation
70%
70%
80%
70%
80%
70%

Wind direction and speed

Altitude above mean sea level
Time
 Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
 900m SE 16mph knots
SE
16mph
 SE 17mph knots
SE
17mph
 E 21mph knots
E
21mph
 E 19mph knots
E
19mph
 N 13mph knots
N
13mph
 NW 11mph knots
NW
11mph
600m
 600m S 11mph knots
S
11mph
 SE 8mph knots
SE
8mph
 E 13mph knots
E
13mph
 E 9mph knots
E
9mph
 N 8mph knots
N
8mph
 NW 7mph knots
NW
7mph
300m
 300m SE 7mph knots
SE
7mph
 SE 3mph knots
SE
3mph
 E 7mph knots
E
7mph
 NE 4mph knots
NE
4mph
 NW 6mph knots
NW
6mph
 NW 5mph knots
NW
5mph
Valley
 Valley SE 7mph knots
SE
7mph
 SE 3mph knots
SE
3mph
 E 6mph knots
E
6mph
 NE 4mph knots
NE
4mph
 NW 5mph knots
NW
5mph
 NW 5mph knots
NW
5mph

Wind gust

Altitude above mean sea level
Time
 Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
 900m 19mph 20mph 26mph 24mph 17mph 13mph
600m
 600m 15mph 13mph 18mph 13mph 11mph 10mph
300m
 300m 13mph 9mph 14mph 9mph 10mph 8mph
Valley
 Valley 13mph 9mph 13mph 8mph 9mph 8mph

Altitude above mean sea level
Time
 Time
06:00
09:00
12:00
15:00
18:00
21:00
900m
 900m 8 degrees Celsius 9 degrees Celsius 8 degrees Celsius 8 degrees Celsius 9 degrees Celsius 9 degrees Celsius
600m
 600m 11 degrees Celsius 12 degrees Celsius 11 degrees Celsius 12 degrees Celsius 12 degrees Celsius 12 degrees Celsius
300m
 300m 14 degrees Celsius 16 degrees Celsius 16 degrees Celsius 16 degrees Celsius 15 degrees Celsius 14 degrees Celsius
Valley
 Valley 16 degrees Celsius 17 degrees Celsius 17 degrees Celsius 17 degrees Celsius 16 degrees Celsius 15 degrees Celsius
Freezing Level Freezing Level
2700m
2900m
3100m
3200m
3100m
2900m

Additional weather information

Meteorologist's view

Waterproofs advisable given heavy persistent rain, and with good navigational skills required in hill fog.

Weather

Briefly dry start across northern areas, but a band of rain will quickly arrive from the southwest. The rain will initially be light, but will quickly become heavy and then persist for much of the day, with only temporary lulls possible. Later the rain eases to become light and patchier in nature. Widespread hill fog will accompany the rain.

Chance of cloud-free hill tops

50% soon decreasing 10% with the rain.

Low cloud and visibility

Extensive low cloud developing this morning with bases between 400-600m, shrouding most peaks. Generally very poor or poor visibilities with hill fog and rain, although initially good with distant hills clearly visible early this morning. Then briefly becoming hazy with nearby hills visible during any rare drier lulls.

Ground conditions

Please see - https://yrwyddfa.live/

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.

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