Snowdonia National Park
Includes all summits in the the northern half of Wales from Plynlimon northwards.
Viewing Forecast For
Snowdonia National Park
Saturday 4th December 2021
Last updated
Fri 3rd Dec 21 at
3:55PM
Summary for all mountain areas
Showers running inland from western coasts on strong to gale force W-NW'ly winds, extending into western Peak & Pennines. Local clusters giving frequent hail or hill snow, chance of thunder. Also risk snow for periods N & E Scotland, may move southwards. Much terrain stays frozen above 600-700m, but locally snow to lower elevations.
Headline for Snowdonia National Park
Cold, squally winds. Snow & hail showers, may become constant at times.
How windy? (On the summits)
West or northwesterly, may vary, but mostly 35 to 40mph, sudden squally gusts around showers over 50mph.
Effect of the wind on you?
Considerable buffeting most of the day, at times difficult walking conditions and significant wind chill on higher terrain.
How Wet?
Frequent showers, hail or snow
Clusters of showers, risk merging to periods of constant precipitation. Less showers toward eastern mid-Wales. Snow on the mountains, sometimes falling below 400m. Hail, risk isolated thunder.
Cloud on the hills?
Often covering tops
Cloud bases varied, but often covering higher mountains above 700-800m through the day. Sometimes below 600m for periods during precipitation. Best breaks inland toward mid-Wales.
Chance of cloud free summits?
20%
Sunshine and air clarity?
Rare if any sun. Visibility sometimes good away from showers, but very poor for periods in cloud and snow/hail.
How Cold? (at 900m)
-1 or -2C. Wind chill in strongest winds near -15C.
Freezing Level
600 to 800m, varied around precipitation.
Viewing Forecast For
Snowdonia National Park
Sunday 5th December 2021
Last updated
Fri 3rd Dec 21 at
3:55PM
How windy? (On the summits)
Northerly, 40mph risk 50mph around dawn into early morning, lessening gradually into afternoon to 25mph.
Effect of the wind on you?
Expect arduous conditions and significant wind chill in morning, tending to lessen gradually into afternoon.
How Wet?
Local showers, snow tops
A few showers coming in from the north onto coastal hills, mostly on/near Llyn Peninsula, perhaps more widely at first. Sleet or snow above about 600m. Mostly dry toward mid-Wales.
Cloud on the hills?
May often cover northern tops
Banks of cloud across Snowdon range and Carneddau, mostly above 700m, with some higher breaks, but some lower patches may occur. Conditions may vary through day. Breaks to higher tops best in mid & west Wales.
Chance of cloud free summits?
40%
Sunshine and air clarity?
Variable cloud, occasional sun, best toward mid-Wales. Visibility very good, locally poor if in showers.
How Cold? (at 900m)
-2C, may rise marginally.
Freezing Level
700m, or a little higher by afternoon.
Viewing Forecast For
Snowdonia National Park
Monday 6th December 2021
Last updated
Fri 3rd Dec 21 at
3:55PM
How windy? (On the summits)
South veering westerly, often in the range 30 to 50mph, risk 60mph, perhaps a brief lull.
Effect of the wind on you?
Expect frequent buffeting across the hills, sometimes arduous or difficult walking conditions with significant wind chill.
How Wet?
Hill snow, then showers with hail
A period of upland snowfall is likely early in the day, falling below 400-500m for a time, becoming gradually sleet or rain to higher levels from the west. Followed by clusters of showers, some heavy with hail.
Cloud on the hills?
Fairly extensive
Cloud bases changing quickly, but often covering higher terrain through the day, extensive in precipitation. Brief glimpses of higher summits. Sometimes shafts of cloud forming to lower slopes.
Chance of cloud free summits?
30%
Sunshine and air clarity?
Brief if any sun. Visibility sometimes good, but very poor during precipitation, appalling if in snow and cloud.
How Cold? (at 900m)
-3C tending to rise slowly to -1C.
Freezing Level
Initially below 600m, but rising toward 800m.
Planning Outlook
Most mountain terrain is likely to stay frozen throughout the week ahead. Sometimes freezing conditions to lower slopes, although some day-to-day variations. Wind speed and direction will vary considerably, intermittent lulls, but then a deep low is expected to affect Britain by Tuesday-Wednesday, bringing stormy conditions, perhaps widely. Further lows are likely to follow later in the week. Extensive snowfalls possible on the hills, a mix of snow and rain lower down. Don't miss our latest video content on the MWIS YouTube channel and across our social media feeds.