Eryri / Snowdonia National Park
Includes all summits in the the northern half of Wales from Pumlumon northwards.
Sunday's Forecast
Moderate breeze, locally gusty
A noticeable breeze, feeling cool where exposed on tops. Locally may be gusty, but unlikely to affect walking progress. 15-25mph.
Patchwork of cloud and sun
Dry most or all day. A mix of cloud and sunshine. Occasional cloud banks drifting over higher slopes, lifting above the tops.
Chilly
Air temperature typically 0 to 5C on higher summits. Feeling distinctly chilly on tops when stationary or where exposed to wind. Take appropriate layers.
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Moderate breeze, locally gusty
A noticeable breeze, feeling cool where exposed on tops. Locally may be gusty, but unlikely to affect walking progress. 15-25mph.
Patchwork of cloud and sun
Dry most or all day. A mix of cloud and sunshine. Occasional cloud banks drifting over higher slopes, lifting above the tops.
Chilly
Air temperature typically 0 to 5C on higher summits. Feeling distinctly chilly on tops when stationary or where exposed to wind. Take appropriate layers.
Viewing Forecast For
Eryri / Snowdonia National Park
Sunday 21st December 2025
Last updated
Sat 20th Dec 25 at
4:29PM
Summary for all mountain areas
A blustery, gusty morning in northern England and Scotland, gales for a time in northwest Scotland, tending to ease. Patchy rain from central Scotland down the spine of the Pennines eases into drizzle over the high tops, drizzle in east Wales too with extensive hill fog in these areas. Best of breaks west Wales and NW Highlands.
Headline for Eryri / Snowdonia National Park
Fog and some drizzle east; drier, brighter western slopes
How windy? (On the summits)
South-southeasterly 20-25mph at dawn, stronger winds pre-dawn, easing to 15-20mph most of the day though stronger gusts may blow over the high tops.
Effect of the wind on you?
Fairly small on many slopes but blustery gusts will blow over the tops from time to time.
How Wet?
Substantially dry during daylight
Some patchy drizzly rain, greatest risk east Wales; many slopes may well stay dry all day, greatest chance west/north. Rain will arrive from the southeast overnight.
Cloud on the hills?
Extensive, some breaks westernmost hills
Cloud shrouds the high tops in Snowdonia NP, sheet-like cloud east Wales with bases down to 500m widely. Slopes to the west of the highest summits will see higher breaks, perhaps some clear tops.
Chance of cloud free summits?
10%; 40% westernmost tops.
Sunshine and air clarity?
Mostly overcast and dull with poor visibility, though glimpses of weak sunshine are likely west of the high tops with good visibility here.
How Cold? (at 900m)
3 or 4C most of the day; some slopes locally 2C to start the day. Warming slightly overnight.
Freezing Level
Above the summits
Viewing Forecast For
Eryri / Snowdonia National Park
Monday 22nd December 2025
Last updated
Sat 20th Dec 25 at
4:29PM
How windy? (On the summits)
Southeasterly 15 to 25mph. Stronger gusts over the summits, may reach 35mph for a few early hours.
Effect of the wind on you?
Blustery at times with marked wind chill where exposed to the wind; walking more strenuous in exposure early.
How Wet?
Early rain and drizzle, gradually drying up
Widespread rain from overnight soon breaks into patchy rain and drizzle, mostly concentrated to high tops and east Wales; trending drier.
Cloud on the hills?
Fairly extensive, low bases east Wales
Fairly extensive over high terrain, lowest bases in east Wales which may reach as low as 500-600m. Highest bases northwestern slopes, though tops will struggle to clear.
Chance of cloud free summits?
20%
Sunshine and air clarity?
Little or no sun. Visibility becomes good out of cloud as morning rain clears.
How Cold? (at 900m)
5C; cooler on the middle elevations of east Wales.
Freezing Level
Above the summits
Viewing Forecast For
Eryri / Snowdonia National Park
Tuesday 23rd December 2025
Last updated
Sat 20th Dec 25 at
4:29PM
How windy? (On the summits)
North-northeasterly 10-20mph, gradually strengthening afternoon.
Effect of the wind on you?
Fairly small, though some noticeable effects in exposure later in the day.
How Wet?
Patchy rain
Patches of rain drifting around, most frequent on mountains north of the A5; rainfall totals likely amount to little elsewhere.
Cloud on the hills?
Fairly extensive
High terrain stays in cloud likely all day, lower banks of cloud will come and go which may reach into valley bottoms earlier in the day. Best chance of higher bases/breaks on the slopes near the Llyn Peninsula/Cardigan Bay.
Chance of cloud free summits?
20%
Sunshine and air clarity?
Little or no sun. Good visibility where below cloud.
How Cold? (at 900m)
3C.
Freezing Level
Above the summits
Planning Outlook
Cloud and patchy rain lingers for a few more days early next week, then a slow change to drier and chiller weather into the Christmas period as high pressure builds to the north. Easterly winds will be dominant, the strongest winds in England and Wales. Cloud may be fairly sheet-like in the east sometimes, though variably more extensive or broken. The coldest air will reach England and Wales on the easterly wind with freezing levels reaching as low as 400-600m in Wales, staying slightly warmer in northern Scotland with freezing levels nearer the high summits for a time under the core of high pressure.