779 m summit in Eryri (Snowdonia). 8 forecast days covering wind, cloud, rain and temperature, updated 5 November 2026 at 16:25 UTC.
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Confidence: Medium
Overall hill weather46Poor
Summit wind · 08:00-17:0015-30 mph easterlySummit gusts · 08:00-17:0030-40 mphFeels like-6 to -2°CPrecipitationUp to around 2 mmCloud-free summit estimate20%Cloud base through day700-1,000 mFreezing levelAbove summitDaylightSunrise 07:18 · Sunset 16:37 · 9.3 hours daylight
The day on the hill
A poor day on the tops of Glasgwm, with the summit in cloud for most of the day.
Wind
On the summit expect an easterly wind of 15–30 mph for most of the day, with gusts of 30–40 mph at the windiest. Lower down on the open hillside it will be more like 5–15 mph. Gusts like that will be noticeable on ridges and open tops, and you will chill quickly when you stop.
Cloud and visibility
Expect the summit to be in cloud for most of the day. The cloud base could be as low as 600–900 m mid-afternoon. In cloud you'll be finding your way without landmarks, so carry navigation you trust and know how to use, with a backup such as a spare battery or a map and compass.
Rain and ground
Drizzle sets in mid-morning.
Warmth and kit
On the tops it will be around 0 to 4°C, feeling like -6 to -2°C in the wind. The freezing level is above the summits. Take a hat, gloves, a windproof and a spare warm layer.
Daylight
Sunset is around 4:35pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
Cloud height is hard to pin down, so the summit could be in or out of cloud at short notice. Things could still change through the day, so keep an eye on the sky.
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.
Morning · 08:00–12:00
PoorSummit winds around 20-30 mph. Gusts around 30-40 mph are possible on exposed ground. Rain is forecast during this period.
44
Afternoon · 12:00–17:00
PoorSummit winds around 15-25 mph. Gusts around 30-40 mph are possible on exposed ground. Rain is forecast during this period.
49
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA mixed night to camp, mainly because of damp air: gusts of about 30 mph.59Mixed · 600 mView detailsHide details
Night beginning Thursday 5 November 2026
Full overnight outlook
A mixed night to camp, mainly because of damp air. Gusts reach about 30 mph on open ground, so peg out well and use the guylines. Look for shelter from the east. It should stay dry. The air is damp at every height we checked (300-600 m), so expect heavy condensation. Leave the vents open. Overnight lows of about 3°C at 300 m. A warm 3-season or 3–4 season bag rated to about 0°C comfort, and a warm mat, should do. Allow more if you sleep cold.
Extensive cloud may limit moonlight. Illumination describes the sunlit part of the Moon, not brightness at your pitch.
Overnight window: 5 Nov, 17:00 GMT to 6 Nov, 08:00 GMT. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.
Elevation reference (open ground)
300 m59 · mixed
Wind / gust
13 mph / 24 mph
Typical / low
3.6°C / 3.2°C · much of the night
In cloud
0% of modelled night
Condensation
High
600 m59 · mixed
Wind / gust
15 mph / 29 mph
Typical / low
3.6°C / 3.2°C · much of the night
In cloud
0% of modelled night
Condensation
High
Warmth planning: As a broad starting point, consider a warm 3-season or 3–4 season bag with an ISO/EN comfort rating at or below about 0°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.
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Daytime · exposed rockClimbing & scramblingBetaPoor conditions for exposed scrambling: gusts of 30–40 mph.Poor32View detailsHide details
Generic exposed-rock guidance
Full climbing & scrambling outlook
Poor conditions for exposed scrambling. The rock is likely to be wet and slippery through the day. Gusts of 30–40 mph could throw you off balance on exposed moves and ridges. Cloud on the tops may make route-finding and retreat harder. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceWet rock likelyPeak gust30-40 mphRain0.4 mm
Main factorsgusts of 30–40 mphwet rock likelymuch of the route may be in cloud
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Thursday 5 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
Summit wind · 08:00-17:005-20 mph southeasterlySummit gusts · 08:00-17:0015-25 mphFeels like-4 to 0°CPrecipitationLittle or noneCloud-free summit estimate70%Cloud base through day600-1,300 mFreezing levelAbove summitDaylightSunrise 07:20 · Sunset 16:35 · 9.2 hours daylight
The day on the hill
A good day on Glasgwm: dry, with light winds.
Wind
On the summit expect light winds of up to 15 mph, mainly south-easterly, with gusts of 15–25 mph at the windiest.
Cloud and visibility
Cloud on the tops early should lift off them by midday. The cloud base could be as low as 600–900 m early in the morning.
Rain and ground
It should stay dry.
Warmth and kit
On the tops it will be around 0 to 4°C, feeling like -4 to 0°C in the wind. The freezing level is above the summits. Take a hat, gloves, a windproof and a spare warm layer.
Daylight
Sunset is around 4:35pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
Cloud height is hard to pin down, so the summit could be in or out of cloud at short notice. Some of the detail could still change, so have a last look at the forecast in the morning before you set off.
Sunshine context Model-grid estimate, not summit sunshine
The surrounding model grid indicates 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.
Morning · 08:00–12:00
MixedSummit winds around 10-20 mph. Gusts around 15-25 mph are possible on exposed ground.
61
Afternoon · 12:00–17:00
ExcellentSummit winds around 5-15 mph. Gusts around 10-20 mph are possible on exposed ground.
89
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA good night for a wild camp: dry, with light winds.84Good · 600 mView detailsHide details
Night beginning Friday 6 November 2026
Full overnight outlook
A good night for a wild camp. Light winds on open ground, gusting no more than about 8 mph. It should stay dry. Overnight lows of about 5°C at 300 m. A 3-season bag rated to about 2°C comfort, and a warm mat, should do. Allow more if you sleep cold.
Cloud may affect views of the Moon. Illumination describes the sunlit part of the Moon, not brightness at your pitch.
Overnight window: 6 Nov, 17:00 GMT to 7 Nov, 08:00 GMT. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.
Elevation reference (open ground)
300 m82 · promising
Wind / gust
3 mph / 7 mph
Typical / low
5.5°C / 5.2°C · much of the night
In cloud
0% of modelled night
Condensation
Moderate
600 m84 · promising
Wind / gust
4 mph / 8 mph
Typical / low
5.5°C / 5.2°C · much of the night
In cloud
0% of modelled night
Condensation
Moderate
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.
Good conditions for exposed scrambling. It should stay mostly dry, but a passing shower could leave the rock damp and slippery. Cloud on the tops may make route-finding and retreat harder. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceDry initially; rain possiblePeak gust15-25 mphRainPossible · 35%
Main concernrain possible despite mostly dry conditions being favoured
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Friday 6 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
A fine day on Glasgwm: dry, with light winds and clear tops for most of the day.
Wind
On the summit expect light winds of up to 10 mph, mainly north-westerly, with gusts of 5–15 mph at the windiest.
Cloud and visibility
The tops are likely to stay mostly clear of cloud, though brief patches cannot be ruled out. The air should be clear, so expect far-reaching views as long as the tops stay clear.
Rain and ground
It should stay dry.
Warmth and kit
On the tops it will be around 2 to 6°C, feeling like -2 to 2°C in the wind. The freezing level is above the summits. Take a warm layer and a hat for the top.
Daylight
Sunset is around 4:35pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
Cloud height is hard to pin down, so the summit could be in or out of cloud at short notice. It's still two days off and could change, so check again nearer the time.
Sunshine context Model-grid estimate, not summit sunshine
The surrounding model grid indicates 4.4 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.
Morning · 08:00–12:00
ExcellentSummit winds around 0-10 mph. Gusts around 5-15 mph are possible on exposed ground.
91
Afternoon · 12:00–17:00
ExcellentSummit winds around 0-10 mph. Gusts around 5-15 mph are possible on exposed ground.
90
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA mixed night to camp, mainly because of damp air: dry, with light winds.59Mixed · 600 mView detailsHide details
Night beginning Saturday 7 November 2026
Full overnight outlook
A mixed night to camp, mainly because of damp air. Light winds on open ground, gusting no more than about 10 mph. It should stay dry. Up around 600 m you'd likely be in cloud for part of the night: damp, and hard to find your way if you need to move. The air is damp at every height we checked (300-600 m), so expect heavy condensation. Leave the vents open. Overnight lows of about 4°C at 600 m. A 3-season bag rated to about 2°C comfort, and a warm mat, should do. Allow more if you sleep cold.
Cloud may affect views of the Moon. Illumination describes the sunlit part of the Moon, not brightness at your pitch.
Overnight window: 7 Nov, 17:00 GMT to 8 Nov, 08:00 GMT. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.
Elevation reference (open ground)
300 m59 · mixed
Wind / gust
4 mph / 10 mph
Typical / low
4.8°C / 4.2°C · much of the night
In cloud
0% of modelled night
Condensation
High
600 m59 · mixed
Wind / gust
5 mph / 12 mph
Typical / low
4.7°C / 4.1°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 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.
Excellent conditions for exposed scrambling. The rock should be mostly dry, though drainage lines and shaded holds may still be damp. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceProbably dryPeak gust5-15 mphRain0.0 mm
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Saturday 7 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
Summit wind · 08:00-17:000-10 mph westerlySummit gusts · 08:00-17:005-15 mphFeels like0 to 4°CPrecipitationLittle or noneCloud-free summit estimate55%Cloud base through day500-1,500 mFreezing levelAbove summitDaylightSunrise 07:24 · Sunset 16:32 · 9.1 hours daylight
The day on the hill
A good day on Glasgwm: dry, with light winds.
Wind
On the summit expect light winds of up to 10 mph, mainly westerly, with gusts of 5–15 mph at the windiest.
Cloud and visibility
Cloud on the tops early should lift off them by midday. The cloud base could be as low as 500–800 m early in the morning. Mist or fog is possible in the valleys early on, clearing by about 10am.
Rain and ground
It should stay dry.
Warmth and kit
On the tops it will be around 2 to 6°C, feeling like 0 to 4°C in the wind. The freezing level is above the summits. Take a warm layer and a hat for the top.
Daylight
Sunset is around 4:30pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
Cloud heights are particularly hard to pin down today. It's still three days off and could change, so check again nearer the time.
Sunshine context Model-grid estimate, not summit sunshine
The surrounding model grid indicates 1.2 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.
Morning · 08:00–12:00
MixedSummit winds around 0-10 mph. Gusts around 5-15 mph are possible on exposed ground.
61
Afternoon · 12:00–17:00
ExcellentSummit winds around 0-10 mph. Gusts around 5-15 mph are possible on exposed ground.
93
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA mixed night to camp, mainly because of damp air: gusts of about 25 mph.54Mixed · 600 mView detailsHide details
Night beginning Sunday 8 November 2026
Full overnight outlook
A mixed night to camp, mainly because of damp air. Gusts reach about 25 mph on open ground, so peg out well and use the guylines. Look for shelter from the southeast. It should stay dry. Up around 600 m you'd likely be in cloud for part of the night: damp, and hard to find your way if you need to move. The air is damp at every height we checked (300-600 m), so expect heavy condensation. Leave the vents open. A cold night, down to about 1°C around 300 m. A warm 3-season or 3–4 season bag rated to about -2°C comfort, and a warm mat, should do. Allow more if you sleep cold.
Warmth planning: As a broad starting point, consider a warm 3-season or 3–4 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.
Good conditions for exposed scrambling. The rock should be mostly dry, though drainage lines and shaded holds may still be damp. Cloud on the tops may make route-finding and retreat harder. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceProbably dryPeak gust5-15 mphRain0.0 mm
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Sunday 8 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
Summit wind · 08:00-17:0015-25 mph southeasterlySummit gusts · 08:00-17:0025-35 mphFeels like-6 to -2°CPrecipitationLittle or noneCloud-free summit estimate55%Cloud base through day500-1,400 mFreezing level700-1,000 mDaylightSunrise 07:25 · Sunset 16:30 · 9.1 hours daylight
The day on the hill
A mixed day on Glasgwm: dry and breezy.
Wind
On the summit expect a south-easterly wind of 15–25 mph for most of the day, with gusts of 25–35 mph at the windiest. Lower down on the open hillside it will be more like 5–15 mph. A wind like that will be noticeable on ridges and open tops, and you will chill quickly when you stop.
Cloud and visibility
Cloud on the tops early should lift off them by midday. The cloud base could be as low as 500–800 m around midday. Mist or fog is possible in the valleys early on, clearing by about 7am.
Rain and ground
It should stay dry.
Warmth and kit
On the tops it will be around 0 to 4°C, feeling like -6 to -2°C in the wind. The freezing level is close to summit height. Take a hat, gloves, a windproof and a spare warm layer.
Daylight
Sunset is around 4:30pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
There is some disagreement between forecast models on wind strength. It's still four days off and could change, so check again nearer the time.
Sunshine context Model-grid estimate, not summit sunshine
The surrounding model grid indicates 1.8 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.
Morning · 08:00–12:00
MixedSummit winds around 15-25 mph. Gusts around 25-35 mph are possible on exposed ground.
55
Afternoon · 12:00–17:00
GoodSummit winds around 15-25 mph. Gusts around 20-30 mph are possible on exposed ground. Summit cloud is more persistent early in this period, with better prospects later.
78
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA poor night to camp on open ground: gusts of about 35 mph.39Poor · 600 mView detailsHide details
Night beginning Monday 9 November 2026
Full overnight outlook
A poor night to camp on open ground. Gusts reach about 35 mph on open ground, so peg out well and use the guylines. Look for shelter from the southeast. Dry to pitch, then some light rain overnight and into the morning, so expect to pack a wet tent. Up around 600 m you'd likely be in cloud for part of the night: damp, and hard to find your way if you need to move. The air is damp at every height we checked (300-600 m), so expect heavy condensation. Leave the vents open. A cold night, down to about 3°C around 600 m. A warm 3-season or 3–4 season bag rated to about 0°C comfort, and a warm mat, should do. Allow more if you sleep cold.
Warmth planning: As a broad starting point, consider a warm 3-season or 3–4 season bag with an ISO/EN comfort rating at or below about 0°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.
Fair conditions for exposed scrambling. The rock should be mostly dry, though drainage lines and shaded holds may still be damp. Gusts of 25–35 mph could throw you off balance on exposed moves and ridges. Cloud on the tops may make route-finding and retreat harder. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceProbably dryPeak gust25-35 mphRainPossible · 20%
Main concernmuch of the route may be in cloud
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Monday 9 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
Summit wind · 08:00-17:0010-30 mph southeasterlySummit gusts · 08:00-17:0030-40 mphFeels like-6 to -2°CPrecipitationUp to around 2 mmCloud-free summit estimate30%Cloud base through day400-700 mFreezing levelAbove summitDaylightSunrise 07:27 · Sunset 16:29 · 9.0 hours daylight
The day on the hill
A poor day on the tops of Glasgwm, with cloud coming and going on the summit.
Wind
On the summit expect a south-easterly wind of around 20–30 mph first thing, easing to 10–20 mph by mid-afternoon, with gusts of 30–40 mph at the windiest. The wind turns southerly around midday. Lower down on the open hillside it will be more like 5–15 mph. Gusts like that will be noticeable on ridges and open tops, and you will chill quickly when you stop.
Cloud and visibility
Expect the summit to be in cloud for most of the day. The cloud base could be as low as 400–700 m mid-afternoon. In cloud you'll be finding your way without landmarks, so carry navigation you trust and know how to use, with a backup such as a spare battery or a map and compass.
Rain and ground
Drizzle for much of the day. Some forecast models keep it drier in the morning.
Warmth and kit
On the tops it will be around 0 to 4°C, feeling like -6 to -2°C in the wind. The freezing level is above the summits. Take a hat, gloves, a windproof and a spare warm layer. Pack waterproofs too, and keep a warm layer dry in your pack.
Daylight
Sunset is around 4:30pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
It's still five days off and could change, so check again nearer the time.
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.
Morning · 08:00–12:00
PoorSummit winds around 20-30 mph. Gusts around 30-40 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.
39
Afternoon · 12:00–17:00
MixedWinds ease compared with the morning. Summit winds around 10-20 mph. Gusts around 15-25 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.
55
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA mixed night to camp, mainly because of the rain: about 4 mm of rain.54Mixed · 600 mView detailsHide details
Night beginning Tuesday 10 November 2026
Full overnight outlook
A mixed night to camp, mainly because of the rain. Light winds on open ground, gusting no more than about 25 mph. Expect about 4 mm of rain, with rain while you pitch and still falling when you pack up. Up around 600 m you'd likely be in cloud for part of the night: damp, and hard to find your way if you need to move. Overnight lows of about 7°C at 600 m. A 3-season bag rated to about 4°C comfort, and a warm mat, should do. Allow more if you sleep cold.
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.
Did this match your night?Share a quick observation to help improve this beta forecast.Give feedback →
Daytime · exposed rockClimbing & scramblingBetaVery poor conditions for exposed scrambling: gusts of 30–40 mph.Poor0View detailsHide details
Generic exposed-rock guidance
Full climbing & scrambling outlook
Very poor conditions for exposed scrambling. The rock is likely to be wet and slippery through the day. Gusts of 30–40 mph could throw you off balance on exposed moves and ridges. Cloud on the tops may make route-finding and retreat harder. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceWet rock likelyPeak gust30-40 mphRain2.8 mm
Main factorsgusts of 30–40 mphwet rock likelymuch of the route may be in cloud
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Tuesday 10 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
A mixed day on Glasgwm, with the summit in cloud for most of the day and drizzle for much of the day.
Wind
On the summit expect light winds of up to 15 mph, mainly south-westerly, with gusts of 15–25 mph at the windiest. Lower down on the open hillside the wind will be light, under 10 mph.
Cloud and visibility
Expect the summit to be in cloud for most of the day. The cloud base could be as low as 400–700 m early in the morning. In cloud you'll be finding your way without landmarks, so carry navigation you trust and know how to use, with a backup such as a spare battery or a map and compass. Mist or fog is possible in the valleys early on, clearing by about 2am.
Rain and ground
Drizzle for much of the day, becoming heavier later. Expect 2–5 mm in total. Some forecast models keep it drier in the afternoon.
Warmth and kit
On the tops it will be around 6 to 10°C, feeling like 4 to 8°C in the wind. The freezing level is above the summits. Pack waterproofs, and keep a warm layer dry in your pack.
Daylight
A short day, with only about 9 hours of daylight. Sunset is around 4:25pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
It's still six days off and could change, so check again nearer the time.
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.
Morning · 08:00–12:00
MixedSummit winds around 10-20 mph. Gusts around 15-25 mph are possible on exposed ground. Rain is forecast during this period.
60
Afternoon · 12:00–17:00
MixedMore rain is expected. Summit winds around 5-15 mph. Gusts around 10-20 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.
58
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA mixed night to camp, mainly because of the rain: about 6 mm of rain.54Mixed · 600 mView detailsHide details
Night beginning Wednesday 11 November 2026
Full overnight outlook
A mixed night to camp, mainly because of the rain. Light winds on open ground, gusting no more than about 11 mph. Expect about 6 mm of rain, mostly early on, so you'll likely pitch in the rain. Up around 600 m you'd likely be in cloud for part of the night: damp, and hard to find your way if you need to move. Overnight lows of about 5°C at 300 m. A 3-season bag rated to about 2°C comfort, and a warm mat, should do. Allow more if you sleep cold.
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.
Poor conditions for exposed scrambling. The rock is likely to be wet and slippery through the day. Cloud on the tops may make route-finding and retreat harder. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceWet rock likelyPeak gust15-25 mphRain6.4 mm
Main factorswet rock likelymuch of the route may be in cloud
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Wednesday 11 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
Summit wind · 08:00-17:000-20 mph northeasterlySummit gusts · 08:00-17:0015-25 mphFeels like-6 to -2°CPrecipitationUp to around 2 mmCloud-free summit estimate35%Cloud base through day600-900 mFreezing levelAbove summitDaylightSunrise 07:31 · Sunset 16:25 · 8.9 hours daylight
The day on the hill
A mixed day on Glasgwm, with cloud coming and going on the summit.
Wind
On the summit expect light winds of up to 15 mph, mainly north-easterly, with gusts of 15–25 mph at the windiest. Lower down on the open hillside the wind will be light, under 10 mph.
Cloud and visibility
Expect the summit to be in cloud for most of the day. The cloud base could be as low as 600–900 m early in the morning. In cloud you'll be finding your way without landmarks, so carry navigation you trust and know how to use, with a backup such as a spare battery or a map and compass.
Rain and ground
Drizzle sets in during the early afternoon.
Warmth and kit
On the tops it will be around 0 to 4°C, feeling like -6 to -2°C in the wind. The freezing level is above the summits. Take a hat, gloves, a windproof and a spare warm layer.
Daylight
A short day, with only about 9 hours of daylight. Sunset is around 4:25pm, so allow time to get off the hill before dark, and carry a head torch.
Forecast confidence
It's still seven days off and could change, so check again nearer the time.
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.
Morning · 08:00–12:00
MixedSummit winds around 0-10 mph. Gusts around 10-20 mph are possible on exposed ground.
63
Afternoon · 12:00–17:00
MixedSummit winds around 10-20 mph. Gusts around 15-25 mph are possible on exposed ground. Rain is forecast during this period.
62
Compare an early start with later conditions. The main forecast above covers the day in more detail.
Overnight · 17:00–08:00Wild campingBetaA poor night to camp on open ground: a frost, down to -1°C.39Poor · 600 mView detailsHide details
Night beginning Thursday 12 November 2026
Full overnight outlook
A poor night to camp on open ground. Gusts reach about 30 mph on open ground, so peg out well and use the guylines. Look for shelter from the northeast. The wind swings from northeasterly to northerly overnight, so a pitch sheltered at dusk may not be by morning. It should stay dry. A frost at every height we checked (300-600 m), down to about -1°C. A warm 3-season or 3–4 season bag rated to about -4°C comfort, and a warm mat, should do. Allow more if you sleep cold.
Extensive cloud may limit moonlight. Illumination describes the sunlit part of the Moon, not brightness at your pitch.
Overnight window: 12 Nov, 17:00 GMT to 13 Nov, 08:00 GMT. Approximate open-horizon times; hills can hide the Moon. Still take a headtorch.
Elevation reference (open ground)
300 m39 · poor
Wind / gust
14 mph / 24 mph
Typical / low
-0.3°C / -0.8°C · much of the night
In cloud
0% of modelled night
Condensation
Low
600 m39 · poor
Wind / gust
17 mph / 29 mph
Typical / low
-0.3°C / -0.8°C · much of the night
In cloud
0% of modelled night
Condensation
Low
Warmth planning: As a broad starting point, consider a warm 3-season or 3–4 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.
Mixed conditions for exposed scrambling. The rock is likely to be wet and slippery through the day. Cloud on the tops may make route-finding and retreat harder. The rock around the summit is mostly rhyolite, a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, taken from geological maps around the summit, so the rock on your line may differ.
Rock surfaceWet rock likelyPeak gust15-25 mphRain0.6 mm
Main factorswet rock likelymuch of the route may be in cloud
Representative rock around the summit
RhyoliteUnnamed Igneous Intrusion, Ordovician
Origin
Igneous
Broad rock-response group
Volcanic rock
Mapping
BGS Geology 50K · 1:50,000
Summit area
Volcanic rock in 100% of 17 BGS samples within 350 m
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose. These are general notes for each rock type, from geological map samples at and around the summit. The rock on your line can differ, and lichen, vegetation and seepage all change how it feels underfoot.
Geological detail and BGS records
Mapped variation
3 rock types appear in the mapped samples
Samples around the summit inform the main rock-response profile, with the summit pin shown separately where it differs. Route samples add further context, but this is not a continuous geological survey.
Rhyolite is a hard, fine-grained volcanic rock. It grips well when dry and gets slippery on smoother faces when wet. It is hard, but often cracked into sharp, blocky pieces, so some holds are loose.
BGS record →
Summit-area sample
Tuff and lavaPistyllion Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
BGS record →
Summit-area sample
Felsic tuffCraig Cau Formation
Volcanic tuff is rock formed from compacted volcanic ash and debris. It is rough and grippy when dry and usually still grips reasonably when wet. It is mostly solid, in slabs and ledges, though weathered patches can be crumbly.
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 Glasgwm on Thursday 12 November 2026. It asks about intentions, not whether you actually went out. No name or account is needed.
