Foel Penolau Weather Forecast – 614m, Eryri (Snowdonia)

Tuesday 22 September 2026Confidence: Medium

Overall hill weather81/100Good

Wind5-15 mph southwesterly Gusts10-20 mph Feels like10 to 14°C PrecipitationLittle or none Cloud-free summit estimate65% Cloud base through day600-900 m Freezing levelAbove summit DaylightSunrise 07:01 · Sunset 19:15 · 12.2 hours daylight

The day on the hill

Little rain and limited summit cloud on Foel Penolau: summit wind broadly 5-15 mph, with gusts 10-20 mph at times (light winds).

Cloud & views

Cloud base mostly around 600–900 m through daylight. The summit is likely to stay mostly clear.

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 confidence

Cloud height remains uncertain, especially where it is close to summit level. Cloud-height uncertainty could put the summit in or out of cloud, even where forecasts agree on the wider cloud cover.

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

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 3.5 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: 1.7 h
Later: 1.7 h

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

Morning · 08:00–12:00 Good Summit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground.

73/100

Afternoon · 12:00–17:00 Excellent Summit winds around 5-15 mph. Gusts around 5-15 mph are possible on exposed ground.

89/100

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

Overnight · 17:00–08:00Wild campingBetaA broadly promising night on a well-chosen pitch. 86/100Excellent · 600 m View detailsHide details

Night beginning Tuesday 22 September 2026

Full overnight outlook

Open-hillside camping looks promising overall around 600 m (86/100). It may be breezy on open ground, with gusts near 25 mph. Little overnight rain is forecast. Some condensation is possible overnight.

Overnight rain0.0 mm Open ground · 600 m10 mph · gusts 25 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 8°C or lower

Moon overnight

Waxing gibbous moon

Illuminated disc: 86%
Moonrise: 17:56 BST
Moonset: 02:50 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: 22 Sep, 17:00 BST to 23 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: 8 mph / 21 mph
Typical / low: 12.8°C / 11.5°C
In cloud: 0% of modelled night
Condensation: Moderate

600 m86/100 · promising

Wind / gust: 10 mph / 25 mph
Typical / low: 12.8°C / 11.5°C
In cloud: 0% of modelled night
Condensation: Moderate

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

Daytime · exposed rockClimbing & scramblingBetaRock is likely to be mostly dry, but check for local dampness. Excellent86/100 View detailsHide details

Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look good (86/100). Rock is likely to be mostly dry, though seepage and shaded holds are not resolved. The mapped summit rock is Sandstone and mudstone (Barmouth Formation). Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully.

Rock surfaceProbably dryPeak gust14 mphRain0.0 mm

Mapped summit rock Sandstone and mudstone Barmouth Formation

Origin: Sedimentary
Rock family: Sandstone or gritstone
Mapping: BGS Geology 50K · 1:50,000
Rock-response profile: High confidence

View the summit BGS record

Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Summit-point bedrock mapping; the actual route may cross different rock, superficial deposits, polish, lichen or seepage.

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

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 Foel Penolau on Tuesday 22 September 2026. It asks about intentions, not whether you actually went out. No name or account is needed.

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Wednesday 23 September 2026Confidence: Medium

Overall hill weather61/100Mixed

Wind10-30 mph northwesterly Gusts30-40 mph Feels like2 to 6°C PrecipitationAround 5-10 mm Cloud-free summit estimate80% Cloud base through day600-1,700 m Freezing levelAbove summit DaylightSunrise 07:02 · Sunset 19:13 · 12.2 hours daylight

The day on the hill

On Foel Penolau: summit wind broadly 10-30 mph, with gusts 30-40 mph at times (strong winds).

Things to watch

Thunderstorms are possible during the morning. Avoid committing to exposed ridges if storms begin to build.

If a thunderstorm develops, sudden gusts and heavy rain can change conditions quickly.

Wind & exposure

Much calmer lower down - generally 5-15 mph in the valley, rising towards the tops.

Cloud & views

Cloud base around 600–900 m in the morning, lifting to 800–1100 m around midday and 1400–1700 m by late afternoon. The summit is likely to stay mostly clear.

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.

Rain & temperature

Some rain is likely, totalling around 5-10 mm, but its timing and local amounts are uncertain. Forecast models differ on summit wind strength: around 21-28 mph at walker height, with gusts 30-40 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. Buffeting may affect balance on exposed ground, particularly near ridges and edges.

Thunderstorm timing is inherently uncertain and may shift by several hours.

Cloud-free timing: Around 50% early, improving to around 95% later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 8 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 h
Midday: 3 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 early in the morning, easing to 10-20 mph later. Gusts around 30-40 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 possible during the morning, but forecast models disagree on whether it will fall.

37/100

Afternoon · 12:00–17:00 Excellent Rain eases compared with the morning. Summit winds around 10-20 mph. Gusts around 20-30 mph are possible on exposed ground.

85/100

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

Overnight · 17:00–08:00Wild campingBetaA broadly very good night on a well-chosen pitch. 91/100Excellent · 600 m View detailsHide details

Night beginning Wednesday 23 September 2026

Full overnight outlook

Open-hillside camping looks very good overall around 600 m (91/100). It may be breezy on open ground, with gusts near 20 mph. Little overnight rain is forecast.

Overnight rain0.0 mm Open ground · 600 m9 mph · gusts 22 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

Clear spells may allow a view of the Moon. 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 / 18 mph
Typical / low: 8.4°C / 8.1°C · much of the night
In cloud: 0% of modelled night
Condensation: Low

600 m91/100 · very good

Wind / gust: 9 mph / 22 mph
Typical / low: 8.4°C / 8.1°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

Daytime · exposed rockClimbing & scramblingBetaModerate thunderstorm risk. Avoid exposed rock if storms develop. Wet rock is likely. Gusts near 35 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 Sandstone and mudstone (Barmouth Formation). Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Gusts may reach about 35 mph. Crosswinds can make exposed ridges substantially more serious. Moderate thunderstorm risk, broadly during the morning. Avoid committing to exposed ground if storms develop.

Rock surfaceWet rock likelyPeak gust36 mphRain5.5 mm

Main factorsmoderate thunderstorm risk on exposed groundgusts around 35 mphwet rock likely

Mapped summit rock Sandstone and mudstone Barmouth Formation

Origin: Sedimentary
Rock family: Sandstone or gritstone
Mapping: BGS Geology 50K · 1:50,000
Rock-response profile: High confidence

View the summit BGS record

Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Summit-point bedrock mapping; the actual route may cross different rock, superficial deposits, polish, lichen or seepage.

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

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

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Thursday 24 September 2026Confidence: High

Overall hill weather82/100Good

Wind10-25 mph southerly Gusts20-30 mph Feels like2 to 6°C PrecipitationLittle or none Cloud-free summit estimate95% Freezing levelAbove summit DaylightSunrise 07:04 · Sunset 19:10 · 12.1 hours daylight

The day on the hill

Little rain and limited summit cloud on Foel Penolau: summit wind broadly 10-25 mph, with gusts 20-30 mph at times (a moderate breeze). Patchy mist is possible in sheltered valleys early on.

Cloud & views

Cloud base around 1200–1500 m in the morning, then around 1700–2000 m around midday and 1000–1300 m by late afternoon. The summit is likely to stay mostly clear.

Rain & temperature

Little or no rain is forecast.

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.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 6.3 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 h
Midday: 3.3 h
Later: 1 h

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

Morning · 08:00–12:00 Good Summit winds around 10-20 mph. Gusts around 20-30 mph are possible on exposed ground.

79/100

Afternoon · 12:00–17:00 Excellent Summit winds around 10-20 mph. Gusts around 20-30 mph are possible on exposed ground.

85/100

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. 54/100Mixed · 600 m View detailsHide details

Night beginning Thursday 24 September 2026

Full overnight outlook

Open-hillside camping looks mixed overall around 600 m (54/100). A lower pitch near 300 m looks more comfortable. Conditions are less suitable by 600 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 600 m. A little rain may coincide with pitching or packing up. Pitches near 600 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 m. Ventilation will matter.

Overnight rain0.7 mm Open ground · 600 m19 mph · gusts 30 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 8°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 m82/100 · promising

Wind / gust: 16 mph / 25 mph
Typical / low: 10.5°C / 10.1°C
In cloud: 0% of modelled night
Condensation: Moderate

600 m54/100 · mixed

Wind / gust: 19 mph / 30 mph
Typical / low: 10.5°C / 10.0°C · a brief spell
In cloud: 53% of modelled night
Condensation: High

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

Daytime · exposed rockClimbing & scramblingBetaRock may be damp or still drying. Good70/100 View detailsHide details

Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look fair (70/100). Some rock may still be damp or drying, especially on polished slabs and vegetated sections. The mapped summit rock is Sandstone and mudstone (Barmouth Formation). Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully.

Rock surfaceDamp or dryingPeak gust26 mphRain0.0 mm

Main concerndamp or incompletely dried rock possible

Mapped summit rock Sandstone and mudstone Barmouth Formation

Origin: Sedimentary
Rock family: Sandstone or gritstone
Mapping: BGS Geology 50K · 1:50,000
Rock-response profile: High confidence

View the summit BGS record

Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Summit-point bedrock mapping; the actual route may cross different rock, superficial deposits, polish, lichen or seepage.

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

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 Foel Penolau 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

Friday 25 September 2026Confidence: Medium

Overall hill weather40/100Poor

Wind10-25 mph westerly Gusts20-30 mph Feels like2 to 6°C PrecipitationAround 5-10 mm Cloud-free summit estimate45% Cloud base through day500-800 m Freezing levelAbove summit DaylightSunrise 07:06 · Sunset 19:08 · 12.0 hours daylight

The day on the hill

A wet day with extensive summit cloud on Foel Penolau: summit wind broadly 10-25 mph, with gusts 20-30 mph at times (a fresh breeze).

Cloud & views

Cloud base mostly around 500–800 m through daylight. Summit cloud is likely, but brief clear spells remain possible if the cloud sits higher than expected.

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

Cloud may hang lower on western slopes and lift somewhat on the eastern 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. The forecast total is around 5-10 mm, but local amounts will vary.

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

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 10 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: 1.4 h
Midday: 4 h
Later: 2.6 h

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

Morning · 08:00–12:00 Poor Summit winds around 15-25 mph. Gusts around 20-30 mph are possible on exposed ground. Rain is forecast during this period. Rain is possible during the morning, but forecast models disagree on whether it will fall.

40/100

Afternoon · 12:00–17:00 Poor More rain is expected. Summit winds around 10-20 mph. Gusts around 20-30 mph are possible on exposed ground. Rain is forecast during this period. Some forecast models bring rain during the afternoon, while others keep it mostly dry.

41/100

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

Overnight · 17:00–08:00Wild campingBetaAbout 1.2 mm is forecast, with rain possible around pitching time. 64/100Mixed · 600 m View detailsHide details

Night beginning Friday 25 September 2026

Full overnight outlook

Open-hillside camping looks reasonable overall around 600 m (64/100). Light winds are expected on open ground, though local shelter and exposure still matter. Around 1.2 mm is forecast, including rain around pitching time. Condensation risk is high near 300 and 600 m, so a wet pack-up is possible. Ventilation will matter.

Overnight rain1.2 mm Open ground · 600 m9 mph · gusts 18 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 4°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 m64/100 · reasonable

Wind / gust: 8 mph / 15 mph
Typical / low: 8.1°C / 7.7°C · much of the night
In cloud: 0% of modelled night
Condensation: High

600 m64/100 · reasonable

Wind / gust: 9 mph / 18 mph
Typical / low: 8.1°C / 7.7°C · much of the night
In cloud: 13% 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 4°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

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Poor7/100 View detailsHide details

Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look very poor (7/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Sandstone and mudstone (Barmouth Formation). Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Cloud may also make route-finding and retreat harder.

Rock surfaceWet rock likelyPeak gust27 mphRain8.3 mm

Main factorswet rock likelymuch of the route may be in cloud

Mapped summit rock Sandstone and mudstone Barmouth Formation

Origin: Sedimentary
Rock family: Sandstone or gritstone
Mapping: BGS Geology 50K · 1:50,000
Rock-response profile: High confidence

View the summit BGS record

Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Summit-point bedrock mapping; the actual route may cross different rock, superficial deposits, polish, lichen or seepage.

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

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 Foel Penolau 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

Saturday 26 September 2026Confidence: Medium

Overall hill weather83/100Good

Wind5-15 mph southwesterly Gusts10-20 mph Feels like4 to 8°C PrecipitationLittle or none Cloud-free summit estimate80% Cloud base through day600-1,700 m Freezing levelAbove summit DaylightSunrise 07:07 · Sunset 19:05 · 12.0 hours daylight

The day on the hill

Little rain and limited summit cloud on Foel Penolau: summit wind broadly 5-15 mph, with gusts 10-20 mph at times (light winds).

Cloud & views

Cloud base around 600–900 m in the morning, lifting to 800–1100 m around midday and 1400–1700 m by late afternoon. The summit is likely to stay mostly clear.

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 confidence

Cloud height remains uncertain, especially where it is close to summit level. Rain timing may shift by several hours, which could change how much of the main walking period stays dry.

Cloud-free timing: Around 50% early, improving to around 95% later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 5.8 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: 4 h
Later: 0 h

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

Morning · 08:00–12:00 Good Summit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground.

84/100

Afternoon · 12:00–17:00 Good Summit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground. Rain is possible during the afternoon, but forecast models disagree on whether it will fall.

82/100

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 82/100. 82/100Good · 600 m View detailsHide details

Night beginning Saturday 26 September 2026

Full overnight outlook

Open-hillside camping looks promising overall around 600 m (82/100). Light winds are expected on open ground, though local shelter and exposure still matter. Little overnight rain is forecast. The coldest temperature falls from about 10.1°C at 300 m to 7.9°C at 600 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 m10 mph · gusts 19 mph Morning pack-upNo wet signal Sleeping-bag warmthISO comfort rating about 4°C or lower

Moon overnight

Near-full moon

Illuminated disc: 100%
Moonrise: 18:42 BST
Moonset: Outside this window

Clear spells may allow a view of 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 m82/100 · promising

Wind / gust: 9 mph / 16 mph
Typical / low: 10.2°C / 10.1°C
In cloud: 0% of modelled night
Condensation: Low

600 m82/100 · promising

Wind / gust: 10 mph / 19 mph
Typical / low: 9.6°C / 7.9°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 4°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

Daytime · exposed rockClimbing & scramblingBetaRock may be damp or still drying. Mixed50/100 View detailsHide details

Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look mixed (50/100). Some rock may still be damp or drying, especially on polished slabs and vegetated sections. The mapped summit rock is Sandstone and mudstone (Barmouth Formation). Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully.

Rock surfaceDamp or dryingPeak gust16 mphRainPossible · 60%

Main concerndamp or incompletely dried rock possible

Mapped summit rock Sandstone and mudstone Barmouth Formation

Origin: Sedimentary
Rock family: Sandstone or gritstone
Mapping: BGS Geology 50K · 1:50,000
Rock-response profile: High confidence

View the summit BGS record

Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Summit-point bedrock mapping; the actual route may cross different rock, superficial deposits, polish, lichen or seepage.

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

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 Foel Penolau 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

Sunday 27 September 2026Confidence: Unavailable

Overall hill weather58/100Mixed

Wind15-30 mph southeasterly Gusts30-40 mph Feels like2 to 6°C PrecipitationUp to around 2 mm Cloud-free summit estimate50% Cloud base through day500-1,000 m Freezing levelAbove summit DaylightSunrise 07:09 · Sunset 19:03 · 11.9 hours daylight

The day on the hill

Light rain for several hours on Foel Penolau: summit wind broadly 15-30 mph, with gusts 30-40 mph at times (a fresh breeze).

Wind & exposure

Much calmer lower down - generally 5-15 mph in the valley, rising towards the tops.

Cloud & views

Cloud base around 700–1000 m in the morning, lowering to 500–800 m around midday. Summit cloud is likely to be limited early, becoming more extensive around midday.

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

Sunny spells are possible away from summit cloud, but may not reach the top while it is in cloud. Drizzle is forecast for much of the day.

The forecast total is up to around 2 mm, but local amounts will vary. Forecast models differ on summit wind strength.

Treat the wind figures as a guide. 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.

Forecast confidence

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

Cloud-free timing: Around 70% early, falling to around 35% later.

Sunshine context Model-grid estimate, not summit sunshine

The surrounding model grid indicates 10.8 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: 1.9 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 Good Summit winds around 10-20 mph. Gusts around 15-25 mph are possible on exposed ground. Some forecast models bring rain during the morning, while others keep it mostly dry.

81/100

Afternoon · 12:00–17:00 Poor Winds strengthen compared with the morning. Summit winds around 15-25 mph. Gusts around 30-40 mph are possible on exposed ground. Rain is forecast during this period.

35/100

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. 54/100Mixed · 600 m View detailsHide details

Night beginning Sunday 27 September 2026

Full overnight outlook

Open-hillside camping looks mixed overall around 600 m (54/100). 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 600 m. Wind direction may change substantially during the night. Shelter that works at dusk may be less effective later. Around 1.6 mm is forecast, with rain liable to affect both pitching and packing up. Pitches near 600 m may spend part of the night in cloud, bringing damp conditions and poor visibility while cloud is present. Condensation risk is high near 300 and 600 m. Ventilation will matter.

Overnight rain1.6 mm Open ground · 600 m17 mph · gusts 30 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 4°C or lower

Moon overnight

Waning gibbous moon

Illuminated disc: 98%
Moonrise: 18:53 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: 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 m64/100 · reasonable

Wind / gust: 14 mph / 25 mph
Typical / low: 11.8°C / 6.0°C · several hours
In cloud: 0% of modelled night
Condensation: High

600 m54/100 · mixed

Wind / gust: 17 mph / 30 mph
Typical / low: 11.0°C / 6.0°C · several hours
In cloud: 60% 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 4°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

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Gusts near 35 mph may affect balance on exposed rock. Poor31/100 View detailsHide details

Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look poor (31/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Sandstone and mudstone (Barmouth Formation). Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Gusts may reach about 35 mph. Crosswinds can make exposed ridges substantially more serious. Cloud may also make route-finding and retreat harder.

Rock surfaceWet rock likelyPeak gust34 mphRain1.8 mm

Main factorsgusts around 35 mphwet rock likelymuch of the route may be in cloud

Mapped summit rock Sandstone and mudstone Barmouth Formation

Origin: Sedimentary
Rock family: Sandstone or gritstone
Mapping: BGS Geology 50K · 1:50,000
Rock-response profile: High confidence

View the summit BGS record

Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Summit-point bedrock mapping; the actual route may cross different rock, superficial deposits, polish, lichen or seepage.

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

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 Foel Penolau 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

Monday 28 September 2026Confidence: Unavailable

Overall hill weather84/100Good

Wind10-25 mph southwesterly Gusts25-35 mph Feels like0 to 4°C PrecipitationAround 2-5 mm Cloud-free summit estimate90% Freezing levelAbove summit DaylightSunrise 07:11 · Sunset 19:01 · 11.8 hours daylight

The day on the hill

A wet day on Foel Penolau: summit wind broadly 10-25 mph, with gusts 25-35 mph at times (a fresh breeze).

Cloud & views

Cloud base around 800–1100 m in the morning, lifting to 1000–1300 m around midday. The summit is likely to stay mostly clear.

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

Drizzle is forecast for much of the day. The forecast total is around 2-5 mm, but local amounts will vary.

Forecast models differ on summit wind strength. Treat the wind figures as a guide.

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.

Forecast confidence

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

Cloud-free timing: Around 75% early, improving to around 95% 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 Good Summit winds around 10-20 mph. Gusts around 15-25 mph are possible on exposed ground. Rain is forecast during this period.

81/100

Afternoon · 12:00–17:00 Excellent Summit winds around 10-20 mph. Gusts around 20-30 mph are possible on exposed ground. Rain is forecast during this period.

86/100

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

Overnight · 17:00–08:00Wild campingBetaAbout 2.2 mm is forecast, with rain possible around pitching time. 64/100Mixed · 600 m View detailsHide details

Night beginning Monday 28 September 2026

Full overnight outlook

Open-hillside camping looks reasonable overall around 600 m (64/100). It may be breezy on open ground, with gusts near 25 mph. Around 2.2 mm is forecast, including rain around pitching time. Condensation risk is high near 300 and 600 m, so a wet pack-up is possible. Ventilation will matter.

Overnight rain2.2 mm Open ground · 600 m14 mph · gusts 26 mph Morning pack-upDampness possible Sleeping-bag warmthISO comfort rating about 2°C or lower

Moon overnight

Waning gibbous moon

Illuminated disc: 94%
Moonrise: 19:07 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 m64/100 · reasonable

Wind / gust: 12 mph / 22 mph
Typical / low: 6.8°C / 5.5°C · much of the night
In cloud: 0% of modelled night
Condensation: High

600 m64/100 · reasonable

Wind / gust: 14 mph / 26 mph
Typical / low: 6.8°C / 5.5°C · much of the night
In cloud: 0% 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 2°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

Daytime · exposed rockClimbing & scramblingBetaWet rock is likely. Poor45/100 View detailsHide details

Generic exposed-rock guidance

Full climbing & scrambling outlook

Conditions for exposed scrambling look mixed (45/100). Rain during the climbing period is likely to leave rock wet and more slippery. The mapped summit rock is Sandstone and mudstone (Barmouth Formation). Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully.

Rock surfaceWet rock likelyPeak gust27 mphRain2.2 mm

Main concernwet rock likely

Mapped summit rock Sandstone and mudstone Barmouth Formation

Origin: Sedimentary
Rock family: Sandstone or gritstone
Mapping: BGS Geology 50K · 1:50,000
Rock-response profile: High confidence

View the summit BGS record

Usually rough and grippy when dry. Damp sandstone and gritstone can feel greasy, and saturated sandstone may be weakened, so let the rock dry fully. Summit-point bedrock mapping; the actual route may cross different rock, superficial deposits, polish, lichen or seepage.

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

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 Foel Penolau 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

Foel Penolau weather forecast.

Choose your hill day.

The day on the hill

Cloud & views

Rain & temperature

Forecast confidence

Full overnight outlook

Moon overnight

Elevation reference (open ground)

Full climbing & scrambling outlook

After dark: aurora and stargazing

The day on the hill

Things to watch

Wind & exposure

Cloud & views

Rain & temperature

Forecast confidence

Full overnight outlook

Moon overnight

Elevation reference (open ground)

Full climbing & scrambling outlook

After dark: aurora and stargazing

The day on the hill

Cloud & views

Rain & temperature

Forecast confidence

Full overnight outlook

Moon overnight

Elevation reference (open ground)

Full climbing & scrambling outlook

After dark: aurora and stargazing

The day on the hill

Cloud & views

Forecast confidence

Full overnight outlook

Moon overnight

Elevation reference (open ground)

Full climbing & scrambling outlook

After dark: aurora and stargazing

The day on the hill

Cloud & views

Rain & temperature

Forecast confidence

Full overnight outlook

Moon overnight

Elevation reference (open ground)

Full climbing & scrambling outlook

After dark: aurora and stargazing

The day on the hill

Wind & exposure

Cloud & views

Forecast confidence

Full overnight outlook

Moon overnight

Elevation reference (open ground)

Full climbing & scrambling outlook

After dark: aurora and stargazing

The day on the hill

Cloud & views

Forecast confidence

Full overnight outlook

Moon overnight

Elevation reference (open ground)

Full climbing & scrambling outlook

After dark: aurora and stargazing

Weather around Foel Penolau.

A forecast is part of the decision.