Snowdonia National Park
Includes all summits in the the northern half of Wales from Plynlimon northwards.
Viewing Forecast For
Snowdonia National Park
Wednesday 23rd September 2020
Last updated
Tuesday 22nd September 2020 at
4:20 PM
Summary for all mountain areas
In Scotland, many places dry, but a few showers moving around slowly, of snow on higher summits. Chilly, but winds light. A complex front drifts east across England & Wales - rain may well largely clear, but risk of showers following, may cluster together.
Headline for Snowdonia National Park
Cool. A few showers. Wind mostly light.
How windy? (On the summits)
Variable, may be mostly northerly, 10 to 20mph, perhaps 25mph after dawn.
Effect of the wind on you?
Mostly small, sometimes blustery. Notable wind chill where exposed on tops.
How Wet?
Occasional hail showers
Overnight rain soon clears southeastwards around dawn. Then often dry, but expect scattered showers, with hail sometimes to low levels, possible snow flurries above 1000m.
Cloud on the hills?
Breaking toward higher slopes
Fairly extensive cloud from dawn, becoming gradually confined to higher slopes, although patches may linger on high tops, briefly returning below 600m around showers.
Chance of cloud free summits?
30% rising to 60%
Sunshine and air clarity?
Lengthy amounts of sunshine, but obscured at times by banks of cloud at various heights. Visibility excellent.
How Cold? (at 900m)
4C
Freezing Level
Above the summits.
Viewing Forecast For
Snowdonia National Park
Thursday 24th September 2020
Last updated
Tuesday 22nd September 2020 at
4:20 PM
How windy? (On the summits)
Some uncertainty: Variable or southwesterly, 15 to 25mph, occasional lulls, but risk 30-40mph for periods.
Effect of the wind on you?
Occasionally small, but risk often blustery and significant wind chill on higher areas, sometimes arduous conditions.
How Wet?
Frequent heavy rain
Pulses of heavy rain are expected to rotate in from the southwest across Wales through the day. Some sustained heavy bursts. Risk of hail and thunder, snow on very highest tops. Intermittently dry east Wales.
Cloud on the hills?
Extensive in rain
Likely covering higher summits most or all day. If rain persists, cloud shrouding hills more extensively, but away from rain, breaks occasionally toward higher tops.
Chance of cloud free summits?
40%
Sunshine and air clarity?
Mostly cloudy, any sun weak through layers of high cloud. Visibility very good away from rain, but poor if rain sets in.
How Cold? (at 900m)
3C.
Freezing Level
Only just above Snowdon summit.
Viewing Forecast For
Snowdonia National Park
Friday 25th September 2020
Last updated
Tuesday 22nd September 2020 at
4:20 PM
How windy? (On the summits)
North to northwesterly, 20 to often 30mph, may reach 40 perhaps 50mph for a time Snowdon range.
Effect of the wind on you?
Considerable buffeting at times on higher terrain, in places arduous conditions; significant wind chill.
How Wet?
Occasional showers, hail
Showers spreading inland from the north, risk locally frequent over a few hours, whilst nearby stays often dry. Hail, or sometimes snow on highest summits in Snowdon range.
Cloud on the hills?
Mostly higher tops
Cloud bases varied, but covering higher summits in Snowdon range perhaps for several hours above 800m, and patches below 600m during showers. Inland and toward mid-Wales often breaking to most tops.
Chance of cloud free summits?
60%
Sunshine and air clarity?
Frequent bursts of bright sunshine. The air quite clear, although slight haze coastal mountains.
How Cold? (at 900m)
2 or 3C.
Freezing Level
Just above highest summits.
Planning Outlook
Generally chilly into the weekend with higher mountains near or just below freezing point, and overnight frost in many valleys, notable early-season low temperatures Highland glens. A complex low pivots eastwards on Thursday - rain focused across England, Wales & southern Scotland. Strong northerly winds follow on Friday with scattered hail showers, snow on the Munros. Pressure builds by Saturday leading to largely dry conditions and very clear air. Early next week, westerly winds are expected to return, with rain at times, low cloud and varied temperatures.