Eryri / Snowdonia Mountain weather forecast table
Confidence
High for unsettled, rather mild and often windy conditions through the coming week, but lower for timings of arrival and clearance of more persistent rain.
Mountain weather hazards
Hazards apply at or above 300m, reflecting the more severe conditions which can occur at altitude.
Severe Chill Effect
Gales
Poor Visibility
Thunderstorms
Mountain weather forecast
Early showery rain then sunny spells and showers. Summit gales.
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
Weather (at 800m) |
|
|
|
|
|
|
Chance of precipitation (at 800m) |
30% | 10% | 20% | 20% | 20% | <05% |
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
SW
43
|
SW
36
|
SW
35
|
SW
35
|
SW
32
|
S
29
|
| 600m |
SW
29
|
SW
23
|
SW
24
|
SW
24
|
S
22
|
S
20
|
| 300m |
SW
16
|
SW
13
|
SW
15
|
S
15
|
S
14
|
S
12
|
| Valley |
SW
16
|
SW
13
|
SW
16
|
S
15
|
S
14
|
S
12
|
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m | 50 | 42 | 43 | 43 | 39 | 35 |
| 600m | 35 | 28 | 32 | 32 | 29 | 26 |
| 300m | 30 | 26 | 27 | 28 | 26 | 23 |
| Valley | 30 | 26 | 28 | 28 | 26 | 23 |
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
5°
|
4°
|
5°
|
5°
|
5°
|
6°
|
| 600m |
7°
|
7°
|
7°
|
7°
|
7°
|
8°
|
| 300m |
9°
|
9°
|
9°
|
9°
|
9°
|
9°
|
| Valley |
10°
|
10°
|
11°
|
11°
|
10°
|
10°
|
| Freezing Level |
1,400m
|
1,300m
|
1,400m
|
1,500m
|
1,700m
|
1,900m
|
| Time | 06:00 | 09:00 | 12:00 | 15:00 | 18:00 | 21:00 |
|---|---|---|---|---|---|---|
| 900m |
-3°
|
-2°
|
-2°
|
-2°
|
-1°
|
0°
|
| 600m |
1°
|
2°
|
2°
|
2°
|
2°
|
4°
|
| 300m |
6°
|
6°
|
6°
|
6°
|
6°
|
7°
|
| Valley |
7°
|
7°
|
8°
|
8°
|
7°
|
8°
|
Additional weather information
Meteorologist's view
Feeling cold at height with gusts around 40mph over ridges and summits.
Weather
A bright day on Monday with sunny spells and the odd shower, perhaps slightly wintry over highest summits. The showers gradually die out but cloud increases through the evening with outbreaks of occasionally heavy rain spreading quickly northeast towards midnight.
Chance of cloud-free hill tops
Around 40% at first soon becoming 75%, falling considerably during the evening.
Low cloud and visibility
Scattered bases around 600m in showers. Broken to overcast bases around 400m developing in evening rain across some areas of the Park. Visibility very good or excellent, but several kilometres in rain and near any showers.
Ground conditions
Please see - https://yrwyddfa.live/
Mountain weather information
Weather
Cloudy with occasionally heavy rain continuing through the early hours but tending to become lighter and patchier around dawn. Outbreaks of rain clear through the first half of the morning to leave sunny spells and blustery showers, with conditions underfoot likely to be very wet, with swollen water courses.
Chance of cloud-free hill tops
Close to zero at first gradually becoming 75% through the late morning and early afternoon.
Maximum wind speed expected
Southwesterly 60-70mph, with gusts around 80mph over ridges and summits.
Temperature
- At 800m Plus 6 to 9 degrees Celsius, falling to plus 3 Celsius after dusk
- Valley Around plus 8 degrees Celsius rising to plus 14 Celsius by early afternoon
- Freezing level Above the summits.
Low cloud and visibility
Periods or persistent cloud 400m, with patches below, at first gradually becoming more occasional above 600-750m through the late morning and early afternoon. Away from cloud, visibility very good or excellent, falling to several kilometres in rain and showers.
Mountain weather information
Wed 10 Dec
Some sunny spells but generally rather a lot of cloud with occasional showers. Strong southwesterly winds, risk of summit gales. Freezing level above the summits.
Thu 11 Dec
Bright start but cloud and outbreaks of occasionally heavy rain spreading east in morning. Strong southwesterly winds becoming more southerly and easing. Freezing levels above summits
Fri 12 Dec
Cloudy with outbreaks of occasionally heavy rain. Fresh southerly winds. Freezing level above summits.
Summit specific forecast
Mountain summit forecast map
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.