Eryri / Snowdonia National Park
Includes all summits in the the northern half of Wales from Pumlumon northwards.
Today's Forecast
Viewing Forecast For
Eryri / Snowdonia National Park
Tuesday 20th May 2025
Last updated
Mon 19th May 25 at
4:30PM
Summary for all mountain areas
Mostly sunny and warm in Scotland; some patchy low fog in the north at dawn. Sunny too in England and Wales, fair weather cloud building afternoon with localised showers. Local heavy bursts later in western areas (including Galloway) with chance of isolated lightning, showers more scattered across the Pennines. Fairly light wind for all.
Headline for Eryri / Snowdonia National Park
Showers forming afternoon, isolated heavy bursts
How windy? (On the summits)
Variable direction, 10mph or less. Brief gusts around showers in the afternoon. Shifting generally west to northwesterly later afternoon into evening with breezes up to 15mph.
Effect of the wind on you?
Negligible
How Wet?
Showers forming afternoon, local heavy bursts
Chance of an odd spot of rain from high cloud in the morning in eastern areas. Increasing risk of showers forming through the afternoon; isolated heavy bursts with chance of lightning later afternoon. Greatest risk further inland and eastward.
Cloud on the hills?
Forming mainly in showers
Patchy mist on some slopes early morning, notably in the east if rain here; soon dissipating. Cloud then largely above the hills. Where showers form, cloud lowering onto tops, fleeing patches to lower elevations.
Chance of cloud free summits?
90%
Sunshine and air clarity?
Sunshine and high cloud; fair weather cloud building in through the afternoon, possibly fairly extensively for little sun later. Visibility excellent, some early haze.
How Cold? (at 900m)
7 or 8C, rising only slightly if at all through the day.
Freezing Level
Above the summits
Viewing Forecast For
Eryri / Snowdonia National Park
Wednesday 21st May 2025
Last updated
Mon 19th May 25 at
4:30PM
How windy? (On the summits)
Northerly 15 to 20mph, strongest winds afternoon into evening.
Effect of the wind on you?
Fairly small
How Wet?
Possible showers
Risk local showers at dawn, soon fading. Chance of localised showers returns later afternoon, though amounting to little.
Cloud on the hills?
Clearing tops
Patches on some slopes in the morning, mainly toward north, lifting above the summits. Returning locally in showers at varied heights.
Chance of cloud free summits?
80%
Sunshine and air clarity?
Patchwork of cloud and sun; best of sun arriving into the afternoon. Visibility excellent.
How Cold? (at 900m)
7C rising to 9 or 10C.
Freezing Level
Above the summits
Viewing Forecast For
Eryri / Snowdonia National Park
Thursday 22nd May 2025
Last updated
Mon 19th May 25 at
4:30PM
How windy? (On the summits)
At dawn, northwesterly 20-25mph. Shifting northerly and easing to 15mph, some stronger breezes in the west at times.
Effect of the wind on you?
Fairly small, some walking impeded at dawn, perhaps some brief stability effects on exposed ridges.
How Wet?
Outbreaks of showers afternoon
Risk of outbreaks of showers in the afternoon, chance of strong or extended spells towards mid-Wales.
Cloud on the hills?
High tops often covered, improving later
Banks of cloud drift over highest tops through the day, less frequent later afternoon. Possibly extensively covered above 900m for a time in the morning. Chance of dawn low sea fog on far western hills.
Chance of cloud free summits?
Chance 40% at dawn, rising to 70%
Sunshine and air clarity?
A patchwork of sunshine, chance of extended cloudy periods midday. Excellent visibility.
How Cold? (at 900m)
6 or 7C, little chance if any.
Freezing Level
Above the summits
Planning Outlook
High pressure weakens into midweek. Some passing rain/showery bursts into Wales and England on Wednesday will lead to a mostly dry Thursday and Friday. A northerly breeze will lower temperatures; freezing levels will lower to high terrain of north and east Scotland for a time. In the short-term, ground conditions remain extensively dry, water courses are very low and the fire risk is very high. Weather turns very unsettled into the weekend as a strong frontal system arrives from the west on Friday night, bringing heavy rain and strong winds to all areas. Showers and a brisk wind will follow into the weekend.