The day on the hill
Little rain and limited summit cloud on Butser Hill: summit wind broadly 0-10 mph, with gusts 5-15 mph at times (light winds). Patchy mist is possible in sheltered valleys early on.
Cloud & views
Cloud base around 900–1200 m in the morning, lifting to 1100–1400 m around midday and 1600–1900 m by late afternoon. The summit is likely to stay mostly clear.
Rain & temperature
Little or no rain is forecast.
Cloud-free timing: Around 80% early, improving to around 95% later.
Sunshine context Model-grid estimate, not summit sunshine
The surrounding model grid indicates 8.2 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.
- Early
- 2.8 h
- Midday
- 2.5 h
- Later
- 1 h
Overnight forecast: 17:00–08:00 (UK local time), in Wild camping below.
Overnight · 17:00–08:00Wild campingBetaCondensation risk is high near 300 m. 64/100Mixed · 300 m View detailsHide details
Full overnight outlook
Open-hillside camping looks reasonable overall around 300 m (64/100). Light winds are expected on open ground, though local shelter and exposure still matter. Little overnight rain is forecast. Condensation risk is high near 300 m, so a wet pack-up is possible. Ventilation will matter.
Moon overnight
Waxing gibbous moon
- Illuminated disc
- 86%
- Moonrise
- 17:36 BST
- Moonset
- 02:44 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)
- Wind / gust
- 8 mph / 15 mph
- Typical / low
- 13.5°C / 11.0°C
- In cloud
- 13% 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.
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Daytime · exposed rockClimbing & scramblingBetaRock is likely to be mostly dry, but check for local dampness. Excellent100/100 View detailsHide details
Full climbing & scrambling outlook
Conditions for exposed scrambling look excellent (100/100). Rock is likely to be mostly dry, though seepage and shaded holds are not resolved. The mapped summit rock is Chalk (Seaford Chalk Formation). Usually positive where it is rough and dry, but polished limestone can become very slippery when wet and seepage may linger.
Usually positive where it is rough and dry, but polished limestone can become very slippery when wet and seepage may linger. Summit-point mapping plus representative BGS bedrock samples along available GPX routes. These are not continuous geological surveys; contacts, superficial deposits and the exposed rock on individual holds may differ.
Rock groups along the sampled routes
These are mapped rock groups, not separate weather forecasts or a ranking of route safety.
Popular Butser Hill
limestone
Geological detail and BGS records
4 rock types appear across the available route samples
The summit type remains the forecast's cautious rock-response reference. Other mapped types show where conditions may behave differently elsewhere on the mountain.
Usually positive where it is rough and dry, but polished limestone can become very slippery when wet and seepage may linger.
BGS recordUsually positive where it is rough and dry, but polished limestone can become very slippery when wet and seepage may linger.
BGS recordUsually positive where it is rough and dry, but polished limestone can become very slippery when wet and seepage may linger.
BGS recordUsually positive where it is rough and dry, but polished limestone can become very slippery when wet and seepage may linger.
BGS recordGeneric 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.
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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.
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