Mountain Weather

Yr Elen weather forecast.

962 m summit in Eryri (Snowdonia). 7 forecast days covering wind, cloud, rain and temperature, updated 22 September 2026 at 16:08 UTC.

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Confidence: Medium
Overall hill weather21/100Poor
Wind15-35 mph northwesterly Gusts35-45 mph Feels like0 to 4°C PrecipitationAround 10-20 mm Cloud-free summit estimate35% Cloud base through day600-1,400 m Freezing levelAbove summit DaylightSunrise 07:02 · Sunset 19:13 · 12.2 hours daylight

The day on the hill

Frequent summit cloud on Yr Elen: summit wind broadly 15-35 mph, with gusts 35-45 mph at times (strong winds). Hill cloud may make navigation difficult, with very poor visibility in wetter spells.

Things to watch

Severe spate risk from the morning into the afternoon, with forecast rain and subsequent runoff. Timings are approximate, not a guarantee of safe crossings afterwards. Burns and unbridged crossings may become difficult or impassable. Turn back if a crossing looks unsafe.

Wind & exposure

Much calmer lower down - generally 10-20 mph in the valley, rising towards the tops.

Cloud & views

Cloud base around 600–900 m through the morning, lifting to 1100–1400 m by late afternoon. The top is likely to drift in and out of cloud, with the best chance of a view from late afternoon into the evening.

Cloud-height uncertainty could put the summit in or out of cloud. Clear spells may be difficult to time.

Cloud may hang lower on northwestern slopes and lift somewhat on the southeastern side, but local terrain can differ. Sunny spells are possible away from summit cloud, but may not reach the top while it is in cloud.

Showers are forecast. Some showers could be heavy.

The forecast total is around 10-20 mm, but local amounts will vary. Cold on exposed tops: air temperature broadly 4 to 8°C, feeling around 0 to 4°C in the wind.

Forecast models differ on summit wind strength: around 25-30 mph at walker height, with gusts 34-42 mph.

Forecast confidence

Cloud height remains uncertain, especially where it is close to summit level. A windproof layer will help, with an extra warm layer for stops.

If clothing gets wet, you can cool more quickly. Keep a dry warm layer protected.

Buffeting may affect balance on exposed ground, particularly near ridges and edges. Rain is forecast during the morning, but models differ considerably on the amount.

Cloud-free timing: Around 15% early, improving to around 75% later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 3.4 h of sunshine. This is not a forecast of time in sunshine on the summit. Use the cloud and views outlook above for the conditions on this mountain.

Cloud may obscure this summit even while the surrounding model grid indicates sunshine. The low cloud-free summit estimate is a reason to be cautious about expecting views.

Early
0 h
Midday
Less than 1 hour
Later
1.9 h

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00 Poor Summit winds around 10-30 mph. Gusts around 35-45 mph are possible on exposed ground. Buffeting may affect balance on exposed ground, particularly near ridges and edges. Rain is forecast during this period. Rain is forecast during the morning, but models differ considerably on the amount.
12/100
Afternoon · 12:00–17:00 Poor Rain eases compared with the morning. Summit winds around 15-25 mph. Gusts around 30-40 mph are possible on exposed ground. Summit cloud is more persistent early in this period, with better prospects later.
30/100

Compare an early start with later conditions. The main forecast above covers the day in more detail.

Overnight · 17:00–08:00Wild campingBetaConditions look very good, but forecast uncertainty caps the grade at 92/100. 92/100Excellent · 600 m View detailsHide details
Night beginning Wednesday 23 September 2026

Full overnight outlook

Open-hillside camping looks very good overall around 600 m (92/100). It may be breezy on open ground, with gusts near 25 mph. Peak gusts range from about 15 mph at 300 m to 25 mph at 900 m. Little overnight rain is forecast. The coldest temperature falls from about 8°C at 300 m to 6.4°C at 900 m. The forecast does not have sufficiently broad dry and light-wind support for an exceptional grade. The grade is capped at 92/100.

Overnight rain0.0 mm Open ground · 600 m9 mph · gusts 20 mph Morning pack-upNo wet signal Sleeping-bag warmthISO comfort rating about 6°C or lower

Moon overnight

Waxing gibbous moon

Illuminated disc
92%
Moonrise
18:10 BST
Moonset
04:08 next morning BST

Views of the Moon may come and go through cloud breaks. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 23 Sep, 17:00 BST to 24 Sep, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Elevation reference (open ground)

300 m92/100 · very good
Wind / gust
8 mph / 17 mph
Typical / low
8.3°C / 8.0°C · much of the night
In cloud
0% of modelled night
Condensation
Low
600 m92/100 · very good
Wind / gust
9 mph / 20 mph
Typical / low
8.3°C / 8.0°C · much of the night
In cloud
0% of modelled night
Condensation
Low
900 m89/100 · very good
Wind / gust
11 mph / 24 mph
Typical / low
6.7°C / 6.4°C · much of the night
In cloud
0% of modelled night
Condensation
Low

Warmth planning: As a broad starting point, consider a 3-season bag with an ISO/EN comfort rating at or below about 6°C. Allow more margin if you sleep cold or expect fatigue, and use an adequate insulated mat. Dampness is possible, so keep the sleep system dry and ensure its insulation remains effective if damp.

Open-hillside reference. A sheltered pitch may be calmer; cols and ridges may be much windier. Tent design and the exact pitch still matter. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback

Approximate height is enough, please do not share an exact wild-camp location.

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Gusts near 40 mph may affect balance on exposed rock. Poor0/100 View detailsHide details
Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look very poor (0/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Siltstone (Nant Ffrancon Subgroup). Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Representative samples along available mapped routes also include Basalt, so rock character and wet-weather behaviour may change across the mountain. Gusts may reach about 40 mph. Crosswinds can make exposed ridges substantially more serious. Cloud may also make route-finding and retreat harder.

Rock surfaceWet rock likelyPeak gust39 mphRain19.6 mm
Main factorsgusts around 40 mphwet rock likelymuch of the route may be in cloud
Mapped rock across the summit and available routes Siltstone Nant Ffrancon Subgroup
Origin
Sedimentary
Rock family
Slate or mudstone
Mapping
BGS Geology 50K · 1:50,000
Rock-response profile
Moderate confidence
View the summit BGS record

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.

Rock groups along the sampled routes

These are mapped rock groups, not separate weather forecasts or a ranking of route safety.

Carneddau Aber Falls

volcanic rock

Geological detail and BGS records
Mapped variation

2 rock types appear across the available route samples

The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.

Summit mapping Siltstone Nant Ffrancon Subgroup

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp.

BGS record
Route sample Basalt Foel Grach Basalt Formation 932–1,053 m samples Seen on Peak Carneddau Aber Falls

Often grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.

BGS record

Generic exposed scrambling terrain; mapped summit-point bedrock is included where available, but route grade, exact rock, polish, drainage and escape options remain unresolved. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Did this match your experience?Tell us about the rock surface and wind to help improve this beta forecast.Give feedback

A broad surface report is enough; you do not need to identify a particular route.

Overnight · Aurora, stars & meteorsAfter darkBetaNight-sky guidance is unavailable for this night. View forecastClose forecast

After dark: aurora and stargazing

Night-sky guidance is unavailable for this night. This does not mean clear skies or no aurora.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

Does the weather shape your plans?Optional hill-user research. One answer helps; further questions are up to you.Take part

Help the Mountain Decisions Project understand how forecasts influence hill days, including when plans stay the same. Findings will be shared publicly as summaries, not individual responses.

This is about Yr Elen on Wednesday 23 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

Open the questions to take part.

About the research and your privacy · Already been out? Share that experience instead

Confidence: High
Overall hill weather83/100Good
Wind10-35 mph southwesterly Gusts35-45 mph Feels like2 to 6°C PrecipitationLittle or none Cloud-free summit estimate85% Cloud base through day1,500-1,800 m Freezing levelAbove summit DaylightSunrise 07:04 · Sunset 19:10 · 12.1 hours daylight

The day on the hill

On Yr Elen: summit wind broadly 10-35 mph, with gusts 35-45 mph at times (strong winds).

Wind & exposure

Much calmer lower down - generally 10-20 mph in the valley, rising towards the tops.

Rain & temperature

The ground is likely to be saturated after recent rain. Expect boggy paths and rapid runoff if more rain arrives.

Little or no rain is forecast. Forecast models differ on summit wind strength: around 24-34 mph at walker height, with gusts 34-47 mph.

Exposed tops may feel chilly in the wind. A windproof layer will help, with an extra warm layer for stops.

Buffeting may affect balance on exposed ground, particularly near ridges and edges.

Cloud-free timing: Around 95% early, falling to around 60% later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 9.3 h of sunshine. This is not a forecast of time in sunshine on the summit. Use the cloud and views outlook above for the conditions on this mountain.

Early
1.2 h
Midday
4 h
Later
2.2 h

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00 Excellent Summit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground.
90/100
Afternoon · 12:00–17:00 Good Winds strengthen compared with the morning. Summit winds around 10-20 mph. Gusts around 20-30 mph are possible on exposed ground.
76/100

Compare an early start with later conditions. The main forecast above covers the day in more detail.

Overnight · 17:00–08:00Wild campingBetaExposed camping is not recommended near 900 m: gusts may reach about 45 mph. Sustained winds may reach about 30 mph at times. Lower sheltered ground may be less exposed, but this forecast does not confirm a suitable pitch or a safe approach. Check its overnight conditions separately. 39/100Poor · 600 m View detailsHide details
Night beginning Thursday 24 September 2026

Full overnight outlook

Exposed camping is not recommended near 900 m: gusts may reach about 45 mph. Sustained winds may reach about 30 mph at times. Lower sheltered ground may be less exposed, but this forecast does not confirm a suitable pitch or a safe approach. Check its overnight conditions separately. Open-hillside camping looks poor overall around 600 m (39/100). Peak gusts range from about 30 mph at 300 m to 45 mph at 900 m. Around 4.6 mm is forecast, including rain around pack-up. Pitches near 600 and 900 m may spend part of the night in cloud, bringing damp conditions and poor visibility while cloud is present. Condensation risk is high near 600 and 900 m. Ventilation will matter.

Overnight rain4.6 mm Open ground · 600 m17 mph · gusts 37 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 6°C or lower

Moon overnight

Waxing gibbous moon

Illuminated disc
97%
Moonrise
18:21 BST
Moonset
05:27 next morning BST

Cloud at the reference camping height may hide the Moon. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 24 Sep, 17:00 BST to 25 Sep, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Elevation reference (open ground)

300 m59/100 · mixed
Wind / gust
14 mph / 30 mph
Typical / low
12.2°C / 9.0°C · a brief spell
In cloud
0% of modelled night
Condensation
Moderate
600 m39/100 · poor
Wind / gust
17 mph / 37 mph
Typical / low
12.0°C / 8.9°C · a brief spell
In cloud
93% of modelled night
Condensation
High
900 m19/100 · very poor
Wind / gust
20 mph / 43 mph
Typical / low
10.5°C / 7.9°C · several hours
In cloud
93% of modelled night
Condensation
High

Warmth planning: As a broad starting point, consider a 3-season bag with an ISO/EN comfort rating at or below about 6°C. Allow more margin if you sleep cold or expect fatigue, and use an adequate insulated mat. Dampness is possible, so keep the sleep system dry and ensure its insulation remains effective if damp.

The ground is likely to be very wet after recent rain. Expect boggy approaches and choose a durable pitch carefully.

Open-hillside reference. A sheltered pitch may be calmer; cols and ridges may be much windier. Tent design and the exact pitch still matter. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback

Approximate height is enough, please do not share an exact wild-camp location.

Daytime · exposed rockClimbing & scramblingBetaRock may be damp or still drying. Gusts near 40 mph may affect balance on exposed rock. Poor39/100 View detailsHide details
Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look poor (39/100). Recent rain may leave seepage and damp rock, especially on shaded sections. The mapped summit rock is Siltstone (Nant Ffrancon Subgroup). Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Representative samples along available mapped routes also include Basalt, so rock character and wet-weather behaviour may change across the mountain. Gusts may reach about 40 mph. Crosswinds can make exposed ridges substantially more serious.

Rock surfaceDry overhead; seepage uncertainPeak gust42 mphRain0.0 mm
Main factorsgusts around 40 mphdamp or incompletely dried rock possible
Mapped rock across the summit and available routes Siltstone Nant Ffrancon Subgroup
Origin
Sedimentary
Rock family
Slate or mudstone
Mapping
BGS Geology 50K · 1:50,000
Rock-response profile
Moderate confidence
View the summit BGS record

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.

Rock groups along the sampled routes

These are mapped rock groups, not separate weather forecasts or a ranking of route safety.

Carneddau Aber Falls

volcanic rock

Geological detail and BGS records
Mapped variation

2 rock types appear across the available route samples

The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.

Summit mapping Siltstone Nant Ffrancon Subgroup

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp.

BGS record
Route sample Basalt Foel Grach Basalt Formation 932–1,053 m samples Seen on Peak Carneddau Aber Falls

Often grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.

BGS record

Generic exposed scrambling terrain; mapped summit-point bedrock is included where available, but route grade, exact rock, polish, drainage and escape options remain unresolved. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Did this match your experience?Tell us about the rock surface and wind to help improve this beta forecast.Give feedback

A broad surface report is enough; you do not need to identify a particular route.

Overnight · Aurora, stars & meteorsAfter darkBetaNight-sky guidance is unavailable for this night. View forecastClose forecast

After dark: aurora and stargazing

Night-sky guidance is unavailable for this night. This does not mean clear skies or no aurora.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

Does the weather shape your plans?Optional hill-user research. One answer helps; further questions are up to you.Take part

Help the Mountain Decisions Project understand how forecasts influence hill days, including when plans stay the same. Findings will be shared publicly as summaries, not individual responses.

This is about Yr Elen on Thursday 24 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

Open the questions to take part.

About the research and your privacy · Already been out? Share that experience instead

Confidence: Medium
Overall hill weather66/100Mixed
Wind10-25 mph westerly Gusts20-30 mph Feels like0 to 4°C PrecipitationAround 2-5 mm Cloud-free summit estimate70% Cloud base through day500-2,200 m Freezing levelAbove summit DaylightSunrise 07:06 · Sunset 19:08 · 12.0 hours daylight

The day on the hill

On Yr Elen: summit wind broadly 10-25 mph, with gusts 20-30 mph at times (a moderate breeze).

Wind & exposure

Much calmer lower down - generally 0-10 mph in the valley, rising towards the tops.

Cloud & views

Cloud base around 500–800 m in the morning, then around 1900–2200 m around midday and 1300–1600 m by late afternoon. Summit cloud is extensive early, becoming less frequent later.

Cloud-height uncertainty could put the summit in or out of cloud. Clear spells may be difficult to time.

Very little direct sunshine is likely, with extensive cloud. Drizzle is forecast for much of the day.

The forecast total is around 2-5 mm, but local amounts will vary. Cold on exposed tops: air temperature broadly 4 to 8°C, feeling around 0 to 4°C in the wind.

Forecast models differ on summit wind strength: around 14-27 mph at walker height, with gusts 17-34 mph.

Rain & temperature

The ground is likely to be wet after recent rain.

Forecast confidence

Cloud height remains uncertain, especially where it is close to summit level. A windproof layer will help, with an extra warm layer for stops.

If clothing gets wet, you can cool more quickly. Keep a dry warm layer protected.

Forecast models differ on whether meaningful rain reaches the hills during the afternoon and evening.

Cloud-free timing: Cloudy early, clearing later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 0 h of sunshine. This is not a forecast of time in sunshine on the summit. Use the cloud and views outlook above for the conditions on this mountain.

Early
0 h
Midday
0 h
Later
0 h

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00 Mixed Summit winds around 5-15 mph. Gusts around 15-25 mph are possible on exposed ground. Rain is forecast during this period. Some forecast models bring rain during the morning, while others keep it mostly dry.
53/100
Afternoon · 12:00–17:00 Good Rain eases compared with the morning. Summit winds around 10-20 mph. Gusts around 20-30 mph are possible on exposed ground. Rain is forecast during this period. Rain is possible during the afternoon, but forecast models disagree on whether it will fall.
79/100

Compare an early start with later conditions. The main forecast above covers the day in more detail.

Overnight · 17:00–08:00Wild campingBetaGusts near 35 mph make meaningful shelter important. 59/100Mixed · 600 m View detailsHide details
Night beginning Friday 25 September 2026

Full overnight outlook

Open-hillside camping looks mixed overall around 600 m (59/100). A lower pitch near 300 m looks more comfortable. Conditions are less suitable by 900 m. Open-ground gusts may reach about 35 mph. Seek meaningful shelter. Peak gusts range from about 25 mph at 300 m to 35 mph at 900 m. Little overnight rain is forecast.

Overnight rain0.0 mm Open ground · 600 m15 mph · gusts 30 mph Morning pack-upNo wet signal Sleeping-bag warmthISO comfort rating about 6°C or lower

Moon overnight

Near-full moon

Illuminated disc
99%
Moonrise
18:31 BST
Moonset
06:48 next morning BST

Clear spells may allow a view of the Moon. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 25 Sep, 17:00 BST to 26 Sep, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Elevation reference (open ground)

300 m88/100 · very good
Wind / gust
13 mph / 25 mph
Typical / low
9.8°C / 8.8°C · much of the night
In cloud
0% of modelled night
Condensation
Low
600 m59/100 · mixed
Wind / gust
15 mph / 30 mph
Typical / low
9.7°C / 8.7°C · much of the night
In cloud
13% of modelled night
Condensation
Low
900 m39/100 · poor
Wind / gust
18 mph / 36 mph
Typical / low
8.2°C / 7.4°C · much of the night
In cloud
13% of modelled night
Condensation
Low

Warmth planning: As a broad starting point, consider a 3-season bag with an ISO/EN comfort rating at or below about 6°C. Allow more margin if you sleep cold or expect fatigue, and use an adequate insulated mat. Dampness is possible, so keep the sleep system dry and ensure its insulation remains effective if damp.

Open-hillside reference. A sheltered pitch may be calmer; cols and ridges may be much windier. Tent design and the exact pitch still matter. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback

Approximate height is enough, please do not share an exact wild-camp location.

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Poor23/100 View detailsHide details
Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look poor (23/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Siltstone (Nant Ffrancon Subgroup). Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Representative samples along available mapped routes also include Basalt, so rock character and wet-weather behaviour may change across the mountain.

Rock surfaceWet rock likelyPeak gust23 mphRain3.8 mm
Main concernwet rock likely
Mapped rock across the summit and available routes Siltstone Nant Ffrancon Subgroup
Origin
Sedimentary
Rock family
Slate or mudstone
Mapping
BGS Geology 50K · 1:50,000
Rock-response profile
Moderate confidence
View the summit BGS record

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.

Rock groups along the sampled routes

These are mapped rock groups, not separate weather forecasts or a ranking of route safety.

Carneddau Aber Falls

volcanic rock

Geological detail and BGS records
Mapped variation

2 rock types appear across the available route samples

The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.

Summit mapping Siltstone Nant Ffrancon Subgroup

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp.

BGS record
Route sample Basalt Foel Grach Basalt Formation 932–1,053 m samples Seen on Peak Carneddau Aber Falls

Often grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.

BGS record

Generic exposed scrambling terrain; mapped summit-point bedrock is included where available, but route grade, exact rock, polish, drainage and escape options remain unresolved. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Did this match your experience?Tell us about the rock surface and wind to help improve this beta forecast.Give feedback

A broad surface report is enough; you do not need to identify a particular route.

Overnight · Aurora, stars & meteorsAfter darkBetaNight-sky guidance is unavailable for this night. View forecastClose forecast

After dark: aurora and stargazing

Night-sky guidance is unavailable for this night. This does not mean clear skies or no aurora.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

Does the weather shape your plans?Optional hill-user research. One answer helps; further questions are up to you.Take part

Help the Mountain Decisions Project understand how forecasts influence hill days, including when plans stay the same. Findings will be shared publicly as summaries, not individual responses.

This is about Yr Elen on Friday 25 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

Open the questions to take part.

About the research and your privacy · Already been out? Share that experience instead

Confidence: Medium
Overall hill weather50/100Mixed
Wind20-35 mph southwesterly Gusts40-50 mph Feels like2 to 6°C PrecipitationUp to around 2 mm Cloud-free summit estimate75% Cloud base through day500-1,800 m Freezing levelAbove summit DaylightSunrise 07:07 · Sunset 19:05 · 12.0 hours daylight

The day on the hill

On Yr Elen: summit wind broadly 20-35 mph, with gusts 40-50 mph at times (strong winds). Patchy mist is possible in sheltered valleys early on.

Wind & exposure

Much calmer lower down - generally 10-20 mph in the valley, rising towards the tops. Summit wind strength is uncertain: around 17-50 mph at walker height, with gusts 24-70 mph.

Check again nearer the time.

Cloud & views

Cloud base around 500–800 m in the morning, lifting to 1500–1800 m around midday. Summit cloud is extensive early, becoming less frequent later.

Summit cloud is uncertain: local cloud may cover the top even where the wider area looks clearer. Sunny spells are possible away from summit cloud, but may not reach the top while it is in cloud.

Drizzle is forecast at times. The forecast total is up to around 2 mm, but local amounts will vary.

Rain & temperature

The ground is likely to be wet after recent rain.

Forecast confidence

Cloud height remains uncertain, especially where it is close to summit level. Exposed tops may feel chilly in the wind.

A windproof layer will help, with an extra warm layer for stops. Buffeting may affect balance on exposed ground, particularly near ridges and edges.

Summit wind could be roughly 17-50 mph, which changes how difficult exposed walking may feel.

Cloud-free timing: Cloudy early, clearing later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 11 h of sunshine. This is not a forecast of time in sunshine on the summit. Use the cloud and views outlook above for the conditions on this mountain.

Early
2 h
Midday
4 h
Later
3 h

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00 Poor Summit winds around 20-30 mph. Gusts around 35-45 mph are possible on exposed ground. Buffeting may affect balance on exposed ground, particularly near ridges and edges. Summit cloud is more persistent early in this period, with better prospects later.
46/100
Afternoon · 12:00–17:00 Mixed Summit winds around 20-35 mph. Gusts around 40-50 mph are possible on exposed ground. Buffeting may affect balance on exposed ground, particularly near ridges and edges. Rain is forecast during this period.
54/100

Compare an early start with later conditions. The main forecast above covers the day in more detail.

Overnight · 17:00–08:00Wild campingBetaExposed camping is not recommended near 600 and 900 m: gusts may reach about 50 mph. Sustained winds may reach about 35 mph at times. Choose an alternative off the exposed hill. Do not rely on finding shelter after setting out. 19/100Poor · 600 m View detailsHide details
Night beginning Saturday 26 September 2026

Full overnight outlook

Exposed camping is not recommended near 600 and 900 m: gusts may reach about 50 mph. Sustained winds may reach about 35 mph at times. Choose an alternative off the exposed hill. Do not rely on finding shelter after setting out. Open-hillside camping looks very poor overall around 600 m (19/100). Peak gusts range from about 35 mph at 300 m to 50 mph at 900 m. Around 1.3 mm is forecast, including rain around pack-up. Pitches near 600 and 900 m may spend part of the night in cloud, bringing damp conditions and poor visibility while cloud is present. The coldest temperature falls from about 10.9°C at 300 m to 9°C at 900 m.

Overnight rain1.3 mm Open ground · 600 m29 mph · gusts 44 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 8°C or lower

Moon overnight

Near-full moon

Illuminated disc
100%
Moonrise
18:41 BST
Moonset
Outside this window

Cloud at the reference camping height may hide the Moon. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 26 Sep, 17:00 BST to 27 Sep, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Elevation reference (open ground)

300 m39/100 · poor
Wind / gust
24 mph / 37 mph
Typical / low
11.6°C / 10.9°C
In cloud
0% of modelled night
Condensation
Moderate
600 m19/100 · very poor
Wind / gust
29 mph / 44 mph
Typical / low
11.3°C / 10.5°C
In cloud
53% of modelled night
Condensation
Moderate
900 m9/100 · very poor
Wind / gust
34 mph / 52 mph
Typical / low
9.6°C / 9.0°C · much of the night
In cloud
53% of modelled night
Condensation
Low

Warmth planning: As a broad starting point, consider a 2-season bag with an ISO/EN comfort rating at or below about 8°C. Allow more margin if you sleep cold or expect fatigue, and use an adequate insulated mat. Dampness is possible, so keep the sleep system dry and ensure its insulation remains effective if damp.

Open-hillside reference. A sheltered pitch may be calmer; cols and ridges may be much windier. Tent design and the exact pitch still matter. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback

Approximate height is enough, please do not share an exact wild-camp location.

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Gusts near 45 mph may affect balance on exposed rock. Poor0/100 View detailsHide details
Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look very poor (0/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Siltstone (Nant Ffrancon Subgroup). Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Representative samples along available mapped routes also include Basalt, so rock character and wet-weather behaviour may change across the mountain. Gusts may reach about 45 mph. Crosswinds can make exposed ridges substantially more serious.

Rock surfaceWet rock likelyPeak gust44 mphRain0.3 mm
Main factorsgusts around 45 mphwet rock likely
Mapped rock across the summit and available routes Siltstone Nant Ffrancon Subgroup
Origin
Sedimentary
Rock family
Slate or mudstone
Mapping
BGS Geology 50K · 1:50,000
Rock-response profile
Moderate confidence
View the summit BGS record

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.

Rock groups along the sampled routes

These are mapped rock groups, not separate weather forecasts or a ranking of route safety.

Carneddau Aber Falls

volcanic rock

Geological detail and BGS records
Mapped variation

2 rock types appear across the available route samples

The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.

Summit mapping Siltstone Nant Ffrancon Subgroup

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp.

BGS record
Route sample Basalt Foel Grach Basalt Formation 932–1,053 m samples Seen on Peak Carneddau Aber Falls

Often grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.

BGS record

Generic exposed scrambling terrain; mapped summit-point bedrock is included where available, but route grade, exact rock, polish, drainage and escape options remain unresolved. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Did this match your experience?Tell us about the rock surface and wind to help improve this beta forecast.Give feedback

A broad surface report is enough; you do not need to identify a particular route.

Overnight · Aurora, stars & meteorsAfter darkBetaNight-sky guidance is unavailable for this night. View forecastClose forecast

After dark: aurora and stargazing

Night-sky guidance is unavailable for this night. This does not mean clear skies or no aurora.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

Does the weather shape your plans?Optional hill-user research. One answer helps; further questions are up to you.Take part

Help the Mountain Decisions Project understand how forecasts influence hill days, including when plans stay the same. Findings will be shared publicly as summaries, not individual responses.

This is about Yr Elen on Saturday 26 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

Open the questions to take part.

About the research and your privacy · Already been out? Share that experience instead

Confidence: Medium
Overall hill weather0/100Severe hill conditions
Wind25-45 mph southwesterly Gusts50-60 mph Feels like2 to 6°C PrecipitationAround 5-10 mm Cloud-free summit estimate15% Cloud base through day500-800 m Freezing levelAbove summit DaylightSunrise 07:09 · Sunset 19:03 · 11.9 hours daylight

The day on the hill

Strong gusts and frequent summit cloud on Yr Elen: summit wind broadly 25-45 mph, with gusts 50-60 mph at times (strong winds).

Things to watch

Thunderstorms are possible from the morning into the evening. Keep an escape route from exposed ridges and descend if thunder develops.

If a thunderstorm develops, sudden gusts and heavy rain can change conditions quickly. Visibility may drop briefly in showers.

Wind & exposure

Much calmer lower down - generally 10-20 mph in the valley, rising towards the tops. Gusts may knock you off balance on exposed ground, even between spells of lighter wind.

Cloud & views

Cloud base mostly around 500–800 m through daylight. Cloud is likely to cover the top for most or all of daylight, with no dependable break.

Cloud may hang lower on southwestern slopes and lift somewhat on the northeastern side, but local terrain can differ. Any sunshine may be confined to lower ground or breaks away from the summit.

Drizzle is forecast for much of the day, with some passing showers too. The forecast total is around 5-10 mm, but local amounts will vary.

Forecast models differ on summit wind strength: around 25-45 mph at walker height, with gusts 35-63 mph.

Forecast confidence

Cloud height remains uncertain, especially where it is close to summit level. Exposed tops may feel chilly in the wind.

A windproof layer will help, with an extra warm layer for stops. If clothing gets wet, you can cool more quickly.

Keep a dry warm layer protected. A low thunderstorm risk remains difficult to time precisely.

0 is the bottom of the scale. Use the hazard details to judge how severe conditions could be.

Cloud-free timing: Around 5% early, improving to around 30% later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 10.9 h of sunshine. This is not a forecast of time in sunshine on the summit. Use the cloud and views outlook above for the conditions on this mountain.

Cloud may obscure this summit even while the surrounding model grid indicates sunshine. The low cloud-free summit estimate is a reason to be cautious about expecting views.

Early
2 h
Midday
4 h
Later
2.9 h

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00 Severe hill conditions Summit winds around 30-40 mph. Gusts around 50-60 mph are possible on exposed ground. Gusts may knock you off balance on exposed ground, even between spells of lighter wind. Rain is forecast during this period. Some forecast models bring rain during the morning, while others keep it mostly dry.
0/100
Afternoon · 12:00–17:00 Poor Summit winds around 30-40 mph in the early afternoon, easing to 20-30 mph later. Gusts around 50-60 mph are possible on exposed ground. Gusts may knock you off balance on exposed ground, even between spells of lighter wind. Rain is forecast during this period. Some forecast models bring rain during the afternoon, while others keep it mostly dry.
1/100

Compare an early start with later conditions. The main forecast above covers the day in more detail.

Overnight · 17:00–08:00Wild campingBetaGusts near 30 mph make meaningful shelter important. 82/100Good · 600 m View detailsHide details
Night beginning Sunday 27 September 2026

Full overnight outlook

Open-hillside camping looks promising overall around 600 m (82/100). A lower pitch near 300 m looks more comfortable. Conditions are less suitable by 900 m. Open-ground gusts may reach about 30 mph. Seek meaningful shelter. Peak gusts range from about 25 mph at 300 m to 30 mph at 900 m. Little overnight rain is forecast. The coldest temperature falls from about 9.5°C at 300 m to 7.3°C at 900 m. Forecast models are not closely enough agreed for an exceptional grade. The grade is capped at 82/100.

Overnight rain0.0 mm Open ground · 600 m11 mph · gusts 27 mph Morning pack-upNo wet signal Sleeping-bag warmthISO comfort rating about 6°C or lower

Moon overnight

Waning gibbous moon

Illuminated disc
98%
Moonrise
18:52 BST
Moonset
Outside this window

Views of the Moon may come and go through cloud breaks. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 27 Sep, 17:00 BST to 28 Sep, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Elevation reference (open ground)

300 m82/100 · promising
Wind / gust
10 mph / 23 mph
Typical / low
10.0°C / 9.5°C · several hours
In cloud
0% of modelled night
Condensation
Low
600 m82/100 · promising
Wind / gust
11 mph / 27 mph
Typical / low
9.5°C / 9.1°C · much of the night
In cloud
13% of modelled night
Condensation
Low
900 m59/100 · mixed
Wind / gust
13 mph / 32 mph
Typical / low
7.4°C / 7.3°C · much of the night
In cloud
13% of modelled night
Condensation
Low

Warmth planning: As a broad starting point, consider a 3-season bag with an ISO/EN comfort rating at or below about 6°C. Allow more margin if you sleep cold or expect fatigue, and use an adequate insulated mat. Dampness is possible, so keep the sleep system dry and ensure its insulation remains effective if damp.

Open-hillside reference. A sheltered pitch may be calmer; cols and ridges may be much windier. Tent design and the exact pitch still matter. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback

Approximate height is enough, please do not share an exact wild-camp location.

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Gusts near 55 mph may affect balance on exposed rock. Low thunderstorm risk. Avoid exposed rock if storms develop. Poor0/100 View detailsHide details
Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look very poor (0/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Siltstone (Nant Ffrancon Subgroup). Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Representative samples along available mapped routes also include Basalt, so rock character and wet-weather behaviour may change across the mountain. Gusts may reach about 55 mph. Crosswinds can make exposed ridges substantially more serious. Cloud may also make route-finding and retreat harder. Low thunderstorm risk, broadly from the morning into the evening. Avoid committing to exposed ground if storms develop.

Rock surfaceWet rock likelyPeak gust53 mphRain6.8 mm
Main factorslow thunderstorm risk on exposed groundgusts around 55 mphwet rock likely
Mapped rock across the summit and available routes Siltstone Nant Ffrancon Subgroup
Origin
Sedimentary
Rock family
Slate or mudstone
Mapping
BGS Geology 50K · 1:50,000
Rock-response profile
Moderate confidence
View the summit BGS record

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.

Rock groups along the sampled routes

These are mapped rock groups, not separate weather forecasts or a ranking of route safety.

Carneddau Aber Falls

volcanic rock

Geological detail and BGS records
Mapped variation

2 rock types appear across the available route samples

The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.

Summit mapping Siltstone Nant Ffrancon Subgroup

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp.

BGS record
Route sample Basalt Foel Grach Basalt Formation 932–1,053 m samples Seen on Peak Carneddau Aber Falls

Often grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.

BGS record

Generic exposed scrambling terrain; mapped summit-point bedrock is included where available, but route grade, exact rock, polish, drainage and escape options remain unresolved. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Did this match your experience?Tell us about the rock surface and wind to help improve this beta forecast.Give feedback

A broad surface report is enough; you do not need to identify a particular route.

Overnight · Aurora, stars & meteorsAfter darkBetaNight-sky guidance is unavailable for this night. View forecastClose forecast

After dark: aurora and stargazing

Night-sky guidance is unavailable for this night. This does not mean clear skies or no aurora.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

Does the weather shape your plans?Optional hill-user research. One answer helps; further questions are up to you.Take part

Help the Mountain Decisions Project understand how forecasts influence hill days, including when plans stay the same. Findings will be shared publicly as summaries, not individual responses.

This is about Yr Elen on Sunday 27 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

Open the questions to take part.

About the research and your privacy · Already been out? Share that experience instead

Confidence: Unavailable
Overall hill weather94/100Excellent
Wind5-15 mph southerly Gusts10-20 mph Feels like2 to 6°C PrecipitationLittle or none Cloud-free summit estimate80% Cloud base through day1,200-2,200 m Freezing levelAbove summit DaylightSunrise 07:11 · Sunset 19:00 · 11.8 hours daylight

The day on the hill

Little rain and limited summit cloud on Yr Elen: summit wind broadly 5-15 mph, with gusts 10-20 mph at times (light winds). Cloud-height uncertainty could put the summit in or out of cloud.

Clear spells may be difficult to time.

Rain & temperature

Little or no rain is forecast. Forecast models disagree markedly on summit wind strength.

Check again nearer the time.

Forecast confidence

Overall confidence is unavailable: insufficient comparable wind, rain guidance.

Cloud-free timing: Around 80% early, falling to around 60% later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 10.9 h of sunshine. This is not a forecast of time in sunshine on the summit. Use the cloud and views outlook above for the conditions on this mountain.

Early
2 h
Midday
4 h
Later
2.9 h

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00 Excellent Summit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground.
92/100
Afternoon · 12:00–17:00 Excellent Summit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground.
97/100

Compare an early start with later conditions. The main forecast above covers the day in more detail.

Overnight · 17:00–08:00Wild campingBetaExposed camping is not recommended near 300, 600 and 900 m: gusts may reach about 60 mph. Sustained winds may reach about 45 mph at times. Choose an alternative off the exposed hill. Do not rely on finding shelter after setting out. 9/100Poor · 600 m View detailsHide details
Night beginning Monday 28 September 2026

Full overnight outlook

Exposed camping is not recommended near 300, 600 and 900 m: gusts may reach about 60 mph. Sustained winds may reach about 45 mph at times. Choose an alternative off the exposed hill. Do not rely on finding shelter after setting out. Open-hillside camping looks very poor overall around 600 m (9/100). Peak gusts range from about 45 mph at 300 m to 60 mph at 900 m. Around 1.8 mm is forecast, including rain around pack-up. Pitches near 900 m may spend part of the night in cloud, bringing damp conditions and poor visibility while cloud is present. The coldest temperature falls from about 10.2°C at 300 m to 7.1°C at 900 m.

Overnight rain1.8 mm Open ground · 600 m21 mph · gusts 53 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 8°C or lower

Moon overnight

Waning gibbous moon

Illuminated disc
94%
Moonrise
19:06 BST
Moonset
Outside this window

Extensive cloud may limit moonlight. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 28 Sep, 17:00 BST to 29 Sep, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Elevation reference (open ground)

300 m19/100 · very poor
Wind / gust
18 mph / 45 mph
Typical / low
11.0°C / 10.2°C
In cloud
0% of modelled night
Condensation
Low
600 m9/100 · very poor
Wind / gust
21 mph / 53 mph
Typical / low
10.6°C / 10.2°C
In cloud
20% of modelled night
Condensation
Low
900 m9/100 · very poor
Wind / gust
25 mph / 61 mph
Typical / low
8.0°C / 7.1°C · much of the night
In cloud
33% of modelled night
Condensation
Low

Warmth planning: As a broad starting point, consider a 2-season bag with an ISO/EN comfort rating at or below about 8°C. Allow more margin if you sleep cold or expect fatigue, and use an adequate insulated mat. Dampness is possible, so keep the sleep system dry and ensure its insulation remains effective if damp.

Open-hillside reference. A sheltered pitch may be calmer; cols and ridges may be much windier. Tent design and the exact pitch still matter. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback

Approximate height is enough, please do not share an exact wild-camp location.

Daytime · exposed rockClimbing & scramblingBetaRock may be damp or still drying. Good80/100 View detailsHide details
Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look good (80/100). Some rock may still be damp or drying, especially on polished slabs and vegetated sections. The mapped summit rock is Siltstone (Nant Ffrancon Subgroup). Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Representative samples along available mapped routes also include Basalt, so rock character and wet-weather behaviour may change across the mountain.

Rock surfaceDamp or dryingPeak gust15 mphRain0.0 mm
Main concerndamp or incompletely dried rock possible
Mapped rock across the summit and available routes Siltstone Nant Ffrancon Subgroup
Origin
Sedimentary
Rock family
Slate or mudstone
Mapping
BGS Geology 50K · 1:50,000
Rock-response profile
Moderate confidence
View the summit BGS record

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.

Rock groups along the sampled routes

These are mapped rock groups, not separate weather forecasts or a ranking of route safety.

Carneddau Aber Falls

volcanic rock

Geological detail and BGS records
Mapped variation

2 rock types appear across the available route samples

The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.

Summit mapping Siltstone Nant Ffrancon Subgroup

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp.

BGS record
Route sample Basalt Foel Grach Basalt Formation 932–1,053 m samples Seen on Peak Carneddau Aber Falls

Often grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.

BGS record

Generic exposed scrambling terrain; mapped summit-point bedrock is included where available, but route grade, exact rock, polish, drainage and escape options remain unresolved. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Did this match your experience?Tell us about the rock surface and wind to help improve this beta forecast.Give feedback

A broad surface report is enough; you do not need to identify a particular route.

Overnight · Aurora, stars & meteorsAfter darkBetaNight-sky guidance is unavailable for this night. View forecastClose forecast

After dark: aurora and stargazing

Night-sky guidance is unavailable for this night. This does not mean clear skies or no aurora.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

Does the weather shape your plans?Optional hill-user research. One answer helps; further questions are up to you.Take part

Help the Mountain Decisions Project understand how forecasts influence hill days, including when plans stay the same. Findings will be shared publicly as summaries, not individual responses.

This is about Yr Elen on Monday 28 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

Open the questions to take part.

About the research and your privacy · Already been out? Share that experience instead

Confidence: Unavailable
Overall hill weather32/100Poor
Wind35-50 mph southwesterly Gusts55-65 mph Feels like-2 to 2°C PrecipitationAround 5-10 mm Cloud-free summit estimate95% Freezing levelAbove summit DaylightSunrise 07:13 · Sunset 18:58 · 11.8 hours daylight

The day on the hill

Strong gusts on Yr Elen: summit wind broadly 35-50 mph, with gusts 55-65 mph at times (gale-force mean winds at times). Heavier showers may bring brief, stronger gusts and rapidly reduced visibility.

Wind & exposure

Much calmer lower down - generally 10-20 mph in the valley, rising towards the tops.

Cloud & views

Cloud base mostly around 1200–1500 m through daylight. The summit is likely to stay mostly clear.

Rain & temperature

Rain and drizzle are forecast for much of the day, with some passing showers too. The forecast total is around 5-10 mm, but local amounts will vary.

Cold on exposed tops: air temperature broadly 4 to 8°C, feeling around -2 to 2°C in the wind. Forecast models disagree markedly on summit wind strength.

Check again nearer the time. A windproof layer will help, with an extra warm layer for stops.

If clothing gets wet, you can cool more quickly. Keep a dry warm layer protected.

The strongest gusts could knock you over on exposed ground. Avoid exposed ridges and edges.

Forecast confidence

Overall confidence is unavailable: insufficient comparable wind, rain guidance.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 6.5 h of sunshine. This is not a forecast of time in sunshine on the summit. Use the cloud and views outlook above for the conditions on this mountain.

Early
0 h
Midday
2.6 h
Later
2.9 h

Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.

Morning · 08:00–12:00 Poor Summit winds around 30-40 mph. Gusts around 50-60 mph are possible on exposed ground. Gusts may knock you off balance on exposed ground, even between spells of lighter wind. Rain is forecast during this period.
31/100
Afternoon · 12:00–17:00 Poor Summit winds around 35-45 mph. Gusts around 50-60 mph are possible on exposed ground. Walking into the wind is likely to be arduous, with buffeting that can knock you off balance. Rain is forecast during this period.
33/100

Compare an early start with later conditions. The main forecast above covers the day in more detail.

Overnight · 17:00–08:00Wild campingBetaExposed camping is not recommended near 300, 600 and 900 m: gusts may reach about 80 mph. Sustained winds may reach about 60 mph at times. Choose an alternative off the exposed hill. Do not rely on finding shelter after setting out. 0/100Poor · 600 m View detailsHide details
Night beginning Tuesday 29 September 2026

Full overnight outlook

Exposed camping is not recommended near 300, 600 and 900 m: gusts may reach about 80 mph. Sustained winds may reach about 60 mph at times. Choose an alternative off the exposed hill. Do not rely on finding shelter after setting out. Open-hillside camping looks very poor overall around 600 m (0/100). Peak gusts range from about 55 mph at 300 m to 80 mph at 900 m. Roughly 19.8 mm is forecast overnight, with rain liable to affect both pitching and packing up. Pitches near 900 m may spend part of the night in cloud, bringing damp conditions and poor visibility while cloud is present. Condensation risk is high near 900 m. Ventilation will matter. The coldest temperature falls from about 9.6°C at 300 m to 7.6°C at 900 m.

Overnight rain19.8 mm Open ground · 600 m44 mph · gusts 69 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 6°C or lower

Moon overnight

Waning gibbous moon

Illuminated disc
87%
Moonrise
19:25 BST
Moonset
Outside this window

Extensive cloud may limit moonlight. Illumination describes the sunlit part of the Moon, not brightness at your pitch.

Overnight window: 29 Sep, 17:00 BST to 30 Sep, 08:00 BST. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.

Elevation reference (open ground)

300 m9/100 · very poor
Wind / gust
37 mph / 57 mph
Typical / low
10.8°C / 9.6°C · a brief spell
In cloud
0% of modelled night
Condensation
Moderate
600 m0/100 · very poor
Wind / gust
44 mph / 69 mph
Typical / low
10.8°C / 9.6°C · a brief spell
In cloud
0% of modelled night
Condensation
Moderate
900 m0/100 · very poor
Wind / gust
52 mph / 81 mph
Typical / low
8.0°C / 7.6°C · much of the night
In cloud
40% of modelled night
Condensation
High

Warmth planning: As a broad starting point, consider a 3-season bag with an ISO/EN comfort rating at or below about 6°C. Allow more margin if you sleep cold or expect fatigue, and use an adequate insulated mat. Dampness is possible, so keep the sleep system dry and ensure its insulation remains effective if damp.

Open-hillside reference. A sheltered pitch may be calmer; cols and ridges may be much windier. Tent design and the exact pitch still matter. Read about sleeping-bag comfort ratings, pitching in strong winds or using the wild-camping forecast.

Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback

Approximate height is enough, please do not share an exact wild-camp location.

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Gusts near 60 mph may affect balance on exposed rock. Poor0/100 View detailsHide details
Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look very poor (0/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Siltstone (Nant Ffrancon Subgroup). Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Representative samples along available mapped routes also include Basalt, so rock character and wet-weather behaviour may change across the mountain. Gusts may reach about 60 mph. Crosswinds can make exposed ridges substantially more serious.

Rock surfaceWet rock likelyPeak gust60 mphRain9.6 mm
Main factorsgusts around 60 mphwet rock likely
Mapped rock across the summit and available routes Siltstone Nant Ffrancon Subgroup
Origin
Sedimentary
Rock family
Slate or mudstone
Mapping
BGS Geology 50K · 1:50,000
Rock-response profile
Moderate confidence
View the summit BGS record

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.

Rock groups along the sampled routes

These are mapped rock groups, not separate weather forecasts or a ranking of route safety.

Carneddau Aber Falls

volcanic rock

Geological detail and BGS records
Mapped variation

2 rock types appear across the available route samples

The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.

Summit mapping Siltstone Nant Ffrancon Subgroup

Often positive when dry, but smooth, polished or slabby sections can become markedly more slippery when damp.

BGS record
Route sample Basalt Foel Grach Basalt Formation 932–1,053 m samples Seen on Peak Carneddau Aber Falls

Often grippy when dry, but volcanic rocks vary widely; wet lichen, smooth holds and local seepage can still make them slippery.

BGS record

Generic exposed scrambling terrain; mapped summit-point bedrock is included where available, but route grade, exact rock, polish, drainage and escape options remain unresolved. Contains British Geological Survey materials © UKRI 2026. How to use the climbing and scrambling forecast.

Did this match your experience?Tell us about the rock surface and wind to help improve this beta forecast.Give feedback

A broad surface report is enough; you do not need to identify a particular route.

Overnight · Aurora, stars & meteorsAfter darkBetaNight-sky guidance is unavailable for this night. View forecastClose forecast

After dark: aurora and stargazing

Night-sky guidance is unavailable for this night. This does not mean clear skies or no aurora.

Recommended kit for this dayWeather-aware packing prompts, plus your core hillwalking kitView kit

For a day hillwalk, not a complete route-specific checklist. Carry navigation and backup you can use, warm and waterproof layers, suitable footwear, food and water, a headtorch, emergency shelter, first aid and a way to call for help. Snow, ice, technical terrain and overnight trips need additional equipment and skills.

Does the weather shape your plans?Optional hill-user research. One answer helps; further questions are up to you.Take part

Help the Mountain Decisions Project understand how forecasts influence hill days, including when plans stay the same. Findings will be shared publicly as summaries, not individual responses.

This is about Yr Elen on Tuesday 29 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

Open the questions to take part.

About the research and your privacy · Already been out? Share that experience instead

Weather data: Open-Meteo (CC BY 4.0). Adapted by Mountain Weather.

Forecast run: 2026-09-22

Keep exploring

Weather around Yr Elen.

Compare the summit forecast with the wider regional picture and nearby peaks before choosing a route.

Regional mountain forecastEryri (Snowdonia)View area →
Carnedd Llewelyn1,064 m · 1.2 km awayForecast →Foel Grach975 m · 1.7 km awayForecast →Garnedd Uchaf925 m · 2.2 km awayForecast →Carnedd Dafydd1,044 m · 2.3 km awayForecast →

A forecast is part of the decision.

Mountain weather can differ sharply from conditions in the valley. Check official warnings, carry appropriate navigation and clothing, and be ready to change the plan. Read how Mountain Weather forecasts are produced and where their limits lie.

Choose another summit