Condition Analysis
AI-powered assessment using site data and 14-day weather history
The last significant rain was 3.8mm on August 25, giving only one full dry day so far; however, today's midday window (low humidity ~69%, decent wind, clearing skies) on this exposed SW-facing hilltop may have allowed useful surface drying. With heavy rain forecast from tomorrow (13.5mm+), today's afternoon offers the only realistic climbing window for the coming week, but conditions should be visually confirmed on arrival.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Callerhues sits at 323m on open moorland with full SW exposure and no tree shelter, meaning wind-driven drying is exceptionally effective here compared to sheltered Fell Sandstone venues.
- The 40-minute approach via the Pennine Way crosses boggy ground — if the bog is saturated, expect the crag base to be damp and internal moisture to be higher than the surface suggests.
- The recent wet spell (7.7mm on Aug 19, 3.0mm on Aug 20, then 3.8mm on Aug 25) means cumulative moisture loading is significant; a brief dry spell of 3 days (Aug 21–23) was interrupted before full drying could occur.
- Permission from Blakelaw Farm is required and no dogs are allowed — plan access in advance as the remote location makes a wasted trip particularly frustrating.
Warnings
2
- Heavy rain forecast for August 27–28 (32mm+) will make the crag unsafe for several days; do not assume a brief dry spell means the rock is ready.
- With only one dry day since last rain and cumulative wetting, holds may be weakened internally even if the surface appears dry — climb conservatively and avoid pulling hard on small holds.
Reasoning
The 3.8mm on August 25 followed a period of repeated wetting (7.9mm on Aug 17, 7.7mm on Aug 19, 3.0mm on Aug 20), meaning the rock has had cumulative moisture loading with only brief drying windows, and just one dry day since the latest rain is insufficient for confident drying of porous Fell Sandstone.
Today's SW aspect, exposed hilltop position, moderate wind (~20 km/h), and a midday clearing to 0% cloud with humidity dropping to 69% provide a useful but limited drying window; the morning was very humid (96–98%) and evening humidity climbs back above 90%, so effective drying is confined to roughly 6 hours.
Given the cumulative wetting over recent weeks (40.5mm in 28 days) and only one dry day, internal moisture levels may still be elevated enough to reduce hold strength, posing a risk of grain loosening on this bold, protection-sparse crag.
Mid-to-late summer conditions are generally favourable for drying, but the recent pattern of repeated Atlantic fronts has kept humidity high (83% average over 7 days), limiting the seasonal advantage.
Contributing Factors
6
3.8mm fell on August 25, providing only one full dry day before today, which is below the recommended minimum of two dry days for porous sandstone.
Repeated rain events over the past 10 days (7.9mm, 7.7mm, 3.0mm, 3.8mm) have kept the rock in a near-continuously damp state with insufficient drying intervals between wettings.
The fully exposed 323m hilltop with SW aspect maximises solar gain and wind-driven evaporation, making this one of the fastest-drying Fell Sandstone venues.
Humidity drops to 69% with clear skies and ~20 km/h wind from late morning through mid-afternoon, providing roughly 6 hours of effective drying.
Humidity was 96% overnight and will return above 90% by evening, limiting the net drying effect to a narrow afternoon window.
13.5mm forecast for August 27 followed by 18.6mm on August 28 will completely reset any drying progress, closing the window for at least 3–4 days after rain stops.
Recommendations
3
- If climbing today, arrive by late morning to maximise the afternoon drying window and visually inspect holds — if the crag base soil is damp or the rock darkens when touched, do not climb.
- Check the approach bog conditions as an early indicator: saturated boggy ground on the Pennine Way approach suggests the crag has not dried sufficiently.
- Do not plan any climbing from August 27 onwards — the forecast heavy rain (32mm+ over two days) will require at least 2–3 full dry days to recover, and the forecast shows no such window.
Previous Analyses
Marginal — Assess Conditions
65%
57 days ago
Four consecutive dry days since the last significant rain (7.7mm on Aug 19, 3.0mm on Aug 20), with improving conditions through today — low humidity afternoon and SW-facing exposed aspect should have allowed reasonable drying. However, the preceding wet period (nearly 19mm across Aug 16–20) and persistently high average humidity (82%) introduce uncertainty, so a visual check on arrival is strongly advised before committing.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Callerhues sits at 323m on open moorland with a SW aspect and full wind exposure, making it one of the faster-drying Fell Sandstone crags — but the 40-minute boggy approach via the Pennine Way itself indicates how saturated the surrounding ground remains.
- The crag's bold highball character means falls are consequential; even marginal dampness weakening iron-oxide holds is a serious safety concern on unprotected routes.
- An easterly wind today and tomorrow is less effective at drying a SW-facing crag than the prevailing westerlies, as the crag face is somewhat sheltered from this wind direction.
- Permission from Blakelaw Farm is required and dogs are not permitted — check access before making the walk in.
Warnings
2
- Rain is forecast from Aug 25 onwards with a significant 12.6mm event on Aug 28 — do not assume conditions will remain acceptable beyond today.
- The bold highball nature of routes here means any residual dampness weakening holds poses an acute safety risk with ground-fall consequences.
Reasoning
The last significant rainfall was 7.7mm on Aug 19 and 3.0mm on Aug 20, giving four dry days by today; however, the cumulative 19mm across Aug 16–20 combined with high average humidity (82%) means internal moisture may not have fully dissipated despite surface drying.
The SW aspect and exposed hilltop position favour drying, but the current easterly wind direction partially shelters the SW face, and today's morning humidity was still 77–83% — only the afternoon window (50–54% RH, ~17°C) provides genuinely good evaporative conditions.
After ~19mm of rain over 4 days followed by 4 days of drying in mixed conditions, internal moisture levels are likely reduced but possibly not below the threshold where iron-oxide holds on Fell Sandstone are fully reliable.
Late August offers reasonable temperatures and daylight hours; no freeze-thaw risk, but the recent pattern of frequent light-to-moderate rain events is typical of a wetter-than-average summer spell.
Contributing Factors
6
No meaningful precipitation since Aug 20 (3.0mm), giving approximately 96 hours of drying time which meets the minimum 2-day guideline for light rain but is borderline given the cumulative totals.
Nearly 19mm fell across Aug 16–20, including two heavier events of 7.9mm and 7.7mm, which would have deeply saturated the porous sandstone.
The south-west facing, fully exposed hilltop position maximises solar gain and wind-driven evaporation, making Callerhues one of the faster-drying Fell Sandstone venues.
Today's easterly wind partially shelters the SW-facing crag face, reducing the wind-driven drying that this site normally benefits from.
Average humidity over the past 7 days is 82%, limiting evaporative potential and slowing internal drying despite dry surface appearances.
2.6mm is forecast for Aug 25 with further rain on Aug 27–29, meaning today may be the only viable climbing window before another prolonged wet spell.
Recommendations
3
- Visit this afternoon (11:00–17:00) when humidity drops to 50–54% and perform a thorough touch-test on holds and check for damp patches at the crag base before climbing.
- Avoid lower sections and any seepage-prone areas where moisture drains and pools — focus on upper, most exposed faces if conditions pass the visual test.
- Be prepared to walk away without climbing; with rain returning tomorrow, the next good window may not open until well after Aug 29.
Marginal — Assess Conditions
65%
58 days ago
Three consecutive dry days following rain on Aug 19–20, with the SW-facing exposed aspect aiding drying, suggest the rock is likely approaching climbable condition — but recent cumulative rainfall (19mm in the last 7 days) and persistently high humidity (85% average) mean internal moisture cannot be ruled out. Climbers should visually and physically assess the rock on arrival before committing.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The 40-minute approach crosses notoriously boggy Pennine Way ground — if the bog is saturated underfoot, the rock may also retain more moisture than expected.
- At 323m on open moorland the crag is fully exposed to wind from all quarters, which is the primary drying advantage at this site and has been working in its favour over the last three dry days.
- Seepage can linger at the base of routes and in horizontal breaks even when the upper face appears dry — check the lowest metre of any route carefully.
- Permission from Blakelaw Farm is required for access; no dogs allowed — plan ahead as the farm may not be attended at all hours.
Warnings
2
- Heavy rainfall of 37mm+ is forecast for Aug 27–28; do not attempt to climb during or immediately after this event.
- Bold, committing routes on Fell Sandstone carry amplified consequences if holds are weakened by residual internal moisture — downgrade your ambitions if any dampness is detected.
Reasoning
The last significant rain was 7.7mm on Aug 19 and 3.0mm on Aug 20, giving roughly 2.5–3 full dry days by end of today; with ~10.7mm falling over those two days, the rock has likely shed most surface moisture but internal saturation may persist given the high average humidity of 85%.
The SW aspect and exposed hilltop position provide good solar radiation and consistent wind (11–17 km/h over the dry days), which together have delivered reasonable drying conditions — though the northerly wind direction on Aug 20–22 was less favourable for a SW-facing crag, and today's SW breeze at only 11.9 km/h is modest.
Fell Sandstone loses up to 32% compressive strength when wet, and with cumulative rain of 19mm in the past week the iron-oxide cemented holds may still be weakened internally — caution is warranted on bold, committing routes where hold failure would be consequential.
Mid-to-late August is generally favourable for drying with reasonable daylight hours and temperatures, though the recent cool spell (avg 11.2°C over 7 days) has slowed evaporation compared to the warmer spell of Aug 11–13.
Contributing Factors
6
No meaningful rain since Aug 20 (3.0mm), providing approximately 2.5–3 days of drying — approaching the minimum '2 dry days' guideline for porous rock.
The fully exposed hilltop with SW aspect maximises available sun and wind, giving Callerhues above-average drying speed for a Fell Sandstone crag.
Average humidity over the last 7 days has been 85%, significantly slowing evaporation and potentially leaving internal moisture trapped despite a dry surface.
19mm over the past 7 days across multiple events (Aug 16–20) means the rock was repeatedly re-wetted before the current dry spell began, extending the required drying time.
The 7-day average temperature of 11.2°C is below seasonal norms and reduces evaporation rate, though today's 17°C is more helpful.
14.6mm on Aug 27 and 22.8mm on Aug 28 will thoroughly re-saturate the rock, closing the current window.
Recommendations
3
- If visiting today or tomorrow, check the base of routes and horizontal breaks for dampness — if the ground beneath the crag is not sandy-dry, consider the rock still too wet internally.
- Prioritise upper, overhanging, or well-drained sections of the crag which will have dried fastest; avoid slab routes or lower sections where moisture lingers.
- Plan to climb by Aug 25 at the latest — heavy rain forecast for Aug 27–28 (37mm+) will close this window for at least 3–4 days afterwards.
Do Not Climb
45%
59 days ago
Despite two dry days since the last significant rain (7.7mm on Aug 19, 3.0mm on Aug 20), persistently high humidity (~86% average over the past week) and moderate temperatures at 323m altitude are slowing drying considerably. The rock may appear surface-dry but is likely still holding internal moisture from the repeated wetting cycle of the past week.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Callerhues sits at 323m on open moorland and catches good breeze, but the prevailing northerly winds of the last two days offer less direct solar warming on this SW-facing crag than usual.
- The past week has seen three separate rain events totalling ~19mm (Aug 17, 19, 20), creating a cumulative saturation problem where the rock never fully dried between wettings.
- The 40-minute boggy approach via the Pennine Way is a useful proxy — if the moorland is still waterlogged, the crag base and lower routes are very likely still damp internally.
- Permission from Blakelaw Farm is required for access; plan ahead as this is a remote venue with no mobile signal in the valley.
Warnings
2
- Do not rely on surface appearance alone — Fell Sandstone can look dry while retaining damaging internal moisture, especially after repeated wetting.
- The iron-oxide holds at Callerhues are small and particularly vulnerable to breakage when the rock is weakened by moisture — broken holds are permanent damage to these irreplaceable routes.
Reasoning
Three rain events in five days (Aug 17: 7.9mm, Aug 19: 7.7mm, Aug 20: 3.0mm) will have repeatedly saturated the porous Fell Sandstone, and only two fully dry days have elapsed since — insufficient for confident internal drying given the high average humidity of 86%.
The SW aspect is currently receiving reduced benefit as recent winds have been northerly (N then NW), and while the exposed hilltop setting helps, temperatures averaging only ~11°C and humidity rarely dropping below 76% mean evaporative drying is proceeding slowly.
With repeated wetting over the past week and inadequate drying time, there is a meaningful risk of weakened iron-oxide cemented holds — the small crimps and edges typical of Callerhues are particularly vulnerable to grain loosening.
Late August at 323m brings shortening days and cooler overnight temperatures (lows of 3–6°C recently), which slow overnight drying and can leave condensation or dew on the rock face in early mornings.
Contributing Factors
6
Three separate rain events totalling ~19mm between Aug 17–20 created cumulative saturation with no chance for the rock to fully dry between them.
The community standard of at least two dry days is barely met, and given the high humidity and moderate temperatures, effective drying time has been shorter than calendar time suggests.
Average humidity of 86% over the past week severely limits net evaporation from the rock surface, extending internal drying times well beyond the two-day minimum.
The exposed moorland position at 323m ensures consistent airflow across the crag face, which is the single most helpful drying factor at this site.
The south-westerly aspect receives good afternoon solar radiation in August, aiding surface and near-surface drying when the sun is out.
Average temperatures of only ~11°C over the past week, with overnight lows dropping to 3–6°C, significantly slow the rate of evaporative drying compared to warmer lowland sites.
Recommendations
3
- Wait at least one more full dry day before visiting — if Aug 23 stays dry and humidity drops, conditions may improve to 'assess on arrival' by Aug 24.
- Check the moorland approach carefully: if the Pennine Way is waterlogged and the crag base feels damp, the rock is almost certainly still wet internally.
- If you do visit, test lower holds and shaded sections with the back of your hand — any coolness or tackiness indicates residual moisture and you should not climb.
Do Not Climb
35%
60 days ago
Callerhues has received significant rain over the past week (20.8mm in 7 days), with the most recent meaningful precipitation being 7.7mm on Aug 19 and 3.0mm on Aug 20, followed by only a trace today — far short of the minimum 2 dry days required. Despite the exposed SW aspect, high ambient humidity (86% average) and cool temperatures (~12°C) are severely limiting drying, and the rock is almost certainly still holding internal moisture.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The exposed hilltop position and SW aspect are strong drying assets, but the persistent high humidity (86% over the past week) is significantly throttling evaporation despite wind.
- The approach via the Pennine Way crosses boggy moorland, which after 20.8mm of rain in the last week will be very wet — waterproof boots and gaiters advisable even when the crag itself is dry.
- At 323m altitude, temperatures have been notably cool for August (averaging under 12°C this week), slowing the drying process considerably compared to lowland Fell Sandstone venues.
- The cumulative rainfall pattern — repeated small-to-moderate events throughout late July and August with few extended dry windows — means the sandstone has had little opportunity to fully dry out internally for weeks.
Warnings
2
- Do not climb today or tomorrow — the rock has had far too little drying time since 10.7mm of rain fell on Aug 19–20 and internal moisture will be high.
- Fell Sandstone loses up to 50% of its compressive strength when wet; holds that feel solid when dry can snap under body weight when the rock is internally saturated.
Reasoning
With 7.7mm on Aug 19 and 3.0mm on Aug 20, plus only a trace today (0.1mm), the rock has had less than one full dry day since the last significant wetting — it is almost certainly still saturated internally despite any surface drying.
The SW aspect and exposed position provide good drying potential, but with average humidity at 86%, temperatures around 12°C, and moderate winds from the north today (limiting direct solar warming of the SW face), effective drying has been minimal since the rain on Aug 19–20.
Given the repeated wetting cycles throughout August with little opportunity for thorough drying, there is elevated risk of weakened holds and grain loosening on this high-porosity Fell Sandstone — climbing now risks both hold breakage and permanent route damage.
Summer conditions should be favourable, but this has been an unusually cool and wet spell for August at altitude, and the rock has behaved more like an autumn pattern with persistent dampness.
Contributing Factors
6
7.7mm on Aug 19 and 3.0mm on Aug 20 delivered over 10mm in two days, requiring a minimum 48–72 hours of dry weather to begin approaching safe conditions.
Only one day has elapsed since the last significant rain (Aug 20), well short of the 2-day minimum dry period required for Fell Sandstone.
Average humidity of 86% over the past week severely limits evaporation rates, meaning even wind and sun cannot compensate adequately.
Average temperatures around 12°C at 323m are well below summer norms and slow the drying process significantly.
The exposed hilltop with SW aspect maximises available solar radiation and wind, providing the best possible drying conditions for this rock type.
Repeated rain events throughout August (45.9mm in 28 days) have given the porous sandstone very few windows to dry out internally, meaning background saturation is elevated.
Recommendations
3
- Wait at least until Aug 24 before considering a visit — by then the rock will have had 4 dry days with improving conditions, though an on-site check will still be essential.
- On arrival, check the ground at the base of the crag: if the soil or sand is visibly moist, the rock is almost certainly still holding internal moisture and should not be climbed.
- Be prepared for a very wet approach across moorland — waterproof footwear is essential and add extra time to the 40-minute walk in.
Do Not Climb
92%
61 days ago
Callerhues received 6.7mm of rain today on top of 7.5mm yesterday and 7.9mm on August 17th — the rock is thoroughly saturated and needs at least two full dry days to begin recovering. With high humidity (85% average over the past week) and cool temperatures, internal moisture levels will remain dangerously high despite the crag's exposed, SW-facing position.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The crag's exposed hilltop position at 323m catches wind well, but northerly winds forecast for Aug 20–21 blow across the SW-facing rock rather than onto it, reducing their drying effectiveness on the climbing surface.
- The 40-minute approach crosses boggy moorland which will be exceptionally waterlogged after the recent wet spell — wet, heavy conditions underfoot are a strong indicator the crag itself is saturated.
- Fell Sandstone at this altitude has experienced repeated wetting events through July and August (49.3mm in 28 days across many small events), meaning the rock has rarely had time to fully dry internally — cumulative saturation is a real concern.
- Routes at Callerhues are bold and committing with limited protection; climbing on weakened, moisture-compromised holds adds unacceptable risk on routes that already demand full confidence in the rock.
Warnings
2
- Fell Sandstone loses up to 50% of its compressive strength when wet — hold breakage is a real danger, especially on Callerhues' bold, sparsely-protected routes.
- The surface may appear dry before the interior has recovered; do not trust visual dryness alone after this prolonged wet spell.
Reasoning
The rock received 6.7mm today, 7.5mm yesterday, and has had only scattered short dry spells amid a persistently wet fortnight (24.2mm in the last 7 days alone), leaving internal moisture levels very high.
Despite the SW aspect and exposed position, the crag has had zero consecutive dry days and humidity has averaged 85% over the past week, so meaningful evaporative drying has not occurred since the last significant rain.
With repeated wetting cycles and no sustained drying period, the sandstone is likely near or above 60% pore saturation, meaning iron oxide cemented holds are significantly weakened and at serious risk of breakage.
Mid-August should offer reasonable drying potential, but this spell of cool, humid, unsettled weather has negated the seasonal advantage, and temperatures have been well below summer norms for Northumberland.
Contributing Factors
6
6.7mm today plus 7.5mm yesterday and 7.9mm on Aug 17th mean the rock has been repeatedly saturated with no recovery window.
There have been no fully dry days since Aug 15th, and even that followed only a brief 4-day dry spell, so internal drying has been negligible.
Average humidity of 85% over the past week severely limits evaporative drying even on an exposed crag.
The hilltop exposure and south-westerly aspect will aid drying once dry weather arrives, but currently this advantage is overwhelmed by the persistent moisture.
Temperatures averaging only 13°C over the past week slow evaporation significantly compared to typical summer conditions.
49.3mm across 28 days with frequent small wetting events means the rock has rarely had a chance to dry internally, raising baseline saturation.
Recommendations
3
- Do not climb today or tomorrow — the rock is saturated and structurally compromised; wait for at least two full dry days.
- Monitor conditions from August 23rd onwards if the forecast dry spell holds, but visually assess the rock and check the base of the crag for residual dampness before committing.
- Check the boggy approach conditions — if the ground is waterlogged at the crag base, the rock is almost certainly still too wet internally.
Do Not Climb
90%
62 days ago
Callerhues has received nearly 13mm of rain in the past 7 days, including 7.9mm on August 17th and 2.9mm today, with further light precipitation still falling; the rock will be thoroughly wet internally. With high humidity (82% average over the past week) and ongoing drizzle today, meaningful drying has not begun and conditions are clearly unsuitable for climbing on this highly porous Fell Sandstone.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The 40-minute Pennine Way approach crosses boggy moorland that will be very wet after recent rain — boots and gaiters recommended even for a recce visit.
- Despite the exposed SW aspect that normally aids drying, the recent run of high humidity (82–90%) and frequent light precipitation has prevented effective evaporation from the porous sandstone.
- At 323m altitude the crag is prone to low cloud and mist, which the 100% cloud cover and near-saturating humidity readings today confirm — this effectively halts surface drying.
- The cumulative 38mm over 28 days represents a prolonged wetting cycle; even during the dry spell (Aug 10–15), humidity remained moderate and the rock likely never fully dried before the latest rain arrived.
Warnings
2
- Climbing on wet Fell Sandstone causes permanent, irreversible damage to holds — the iron oxide features that define Callerhues' routes are especially fragile when saturated.
- The boggy Pennine Way approach will be treacherous after this wet spell; allow extra time and take care on the moorland crossing.
Reasoning
The rock has received 7.9mm on Aug 17, 0.4mm on Aug 18, and 2.9mm today (Aug 19), with drizzle continuing through the afternoon and evening — the sandstone is saturated or near-saturated internally.
No meaningful drying has occurred since the Aug 17 heavy rain; humidity has been 86–99% with intermittent precipitation every day since, and the SW aspect has had no sun through 100% cloud cover today.
With the rock likely at or above 60% pore saturation from cumulative recent wetting, compressive strength will be significantly reduced (potentially 30%+ loss), making hold breakage and permanent surface damage a serious risk.
Mid-August should be a reasonable climbing window, but this unsettled spell with cool temperatures (14–16°C) and persistent high humidity is producing winter-like drying conditions that demand extra patience.
Contributing Factors
6
7.9mm fell on Aug 17, followed by 0.4mm on Aug 18, and 2.9mm today — a cumulative wetting event on already-moist rock.
Today's hourly data shows ~2.9mm of drizzle scattered throughout the day with more forecast into the evening, meaning zero drying hours have elapsed.
Humidity has averaged 82% over the past week with peaks near 99%, severely limiting evaporative drying even when rain pauses.
The hilltop exposure and SW facing would normally accelerate drying, but this advantage is negated by overcast skies and saturating humidity.
38mm over 28 days with only brief dry spells means the sandstone has been subjected to repeated wetting cycles without adequate time to fully dry between events.
Temperatures of 11–15°C with 100% cloud cover today provide minimal thermal energy to drive evaporation from the rock.
Recommendations
3
- Do not climb today or tomorrow — the rock is wet from ongoing rain and needs at least 2 full dry days before conditions can be assessed.
- Monitor the forecast from Aug 22 onwards; if the dry spell holds with dropping humidity, an on-site assessment may be warranted by Aug 23.
- If visiting, use the muddy-ground field test at the crag base: if the soil and sand beneath the crag are not bone-dry, the rock interior is still holding moisture.
Do Not Climb
92%
63 days ago
The rock is wet today: 7.2mm fell on the 17th, 1.6mm today (mostly overnight), and there have been zero consecutive dry days. With further rain forecast tomorrow (4.4mm) and a heavy event on the 20th (18.4mm), conditions will not be suitable for climbing for several days.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Callerhues sits at 323m on exposed moorland, so the 40-minute Pennine Way approach crosses boggy ground that will be very wet after recent rain — boots and gaiters advisable even for a recce.
- The SW aspect and hilltop exposure are the crag's biggest drying assets, but 100% cloud cover today and high humidity negate much of that advantage.
- The crag's bold, committing routes (often unprotected highball style) make damp holds especially dangerous — a slip from poor friction on weakened sandstone could be serious with limited gear.
- Seepage at the base of the crag is likely given cumulative rainfall of ~10.5mm in the last 7 days; check for damp ground at the cliff foot as a reliable proxy for internal moisture.
Warnings
2
- Climbing on wet Fell Sandstone causes permanent, irreversible damage to holds — the iron-oxide features that define routes here cannot regenerate.
- The bold highball nature of many routes at Callerhues means a slip on damp, weakened rock could result in a ground fall with serious injury.
Reasoning
With 7.2mm on Aug 17, 1.6mm today, and no dry days since, the rock is almost certainly saturated internally despite any surface drying from the strong westerly wind.
The exposed SW aspect and 25–33 km/h winds today would normally aid drying, but 100% cloud cover, humidity in the 70–99% range, and ongoing light precipitation prevent meaningful evaporation.
Fell Sandstone loses up to 50% compressive strength when wet, and with recent repeated wetting events over the past two weeks (35.6mm in 28 days with no sustained dry spells), the iron-oxide holds are at significant breakage risk.
Mid-August should be prime season, but this has been an unsettled spell with above-average rainfall; the pattern of repeated light wetting without sustained drying periods means cumulative moisture is high.
Contributing Factors
6
7.2mm on Aug 17 plus 1.6mm today means the rock has been freshly wetted with no drying window.
There has not been a single fully dry day since Aug 15, and before that the last proper dry spell was Aug 10–15.
The past 28 days have seen 35.6mm spread across many small events, preventing the rock from ever fully drying out internally.
Sustained 20–33 km/h westerly winds on this exposed hilltop would accelerate surface drying if rain stopped.
Humidity has averaged 79% over the past week and today's cloud cover is 100%, severely limiting evaporative drying.
4.4mm forecast tomorrow and 18.4mm on Aug 20 will reset any drying progress and saturate the rock further.
Recommendations
3
- Do not climb today or in the next few days — wait for at least two full dry days after the heavy rain forecast on Aug 20.
- The earliest realistic window is Aug 22–23 if the forecast holds dry; check ground moisture at the crag base before touching the rock.
- Use the waiting time to plan the approach logistics — confirm permission from Blakelaw Farm and prepare for the boggy Pennine Way walk-in.
Do Not Climb
95%
64 days ago
Callerhues is currently wet and receiving more rain today, with a prolonged wet spell forecast through at least August 21st. The rock has had no meaningful drying window since the last significant rainfall on August 16th (1.1mm) and today's 8.4mm, and further rain is expected every day until August 22nd — the crag will remain saturated throughout.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The 40-minute boggy Pennine Way approach will be extremely waterlogged after the recent and ongoing wet spell, making access unpleasant and slow.
- Despite the SW aspect and exposed hilltop aiding drying in good conditions, persistent high humidity (86%+) and continuous rain negate these advantages entirely.
- The crag has seen a cumulative ~35mm over the past 28 days with no sustained dry period longer than 5 days, meaning the sandstone's internal moisture level is likely elevated even before recent rain.
- At 323m altitude, temperatures are forecast to drop to ~13–15°C with high humidity, further slowing any drying that might otherwise occur between showers.
Warnings
2
- Climbing today or in the coming days would risk permanent damage to irreplaceable Fell Sandstone holds — the rock is saturated and structurally weakened.
- The boggy Pennine Way approach will be treacherous in current conditions; plan for significantly longer approach times if visiting later.
Reasoning
The rock is almost certainly saturated: 8.4mm fell today with additional heavy rain tonight (6.8mm forecast from 22:00–23:00), following 1.1mm yesterday, and the preceding weeks have been intermittently wet with no extended dry period.
Despite the SW aspect and exposed position, there has been zero effective drying since the last rain — today's humidity reached 94–99% overnight and rain continues this evening, with further rain forecast daily through August 21st.
With the sandstone likely at or above 60% pore saturation from cumulative recent rainfall, climbing would risk significant hold breakage and permanent route damage given Fell Sandstone's 10–50% compressive strength loss when wet.
Mid-August should offer reasonable drying potential, but this particular spell is unusually wet and cool for summer, with temperatures and humidity more typical of autumn conditions at this altitude.
Contributing Factors
6
8.4mm has fallen or is falling today, with a further ~7mm forecast this evening, thoroughly wetting the rock.
Zero consecutive dry days — the minimum 2-day drying requirement for Fell Sandstone cannot begin until rain stops.
Rain is forecast every day from August 18th through August 21st (totalling ~18mm), preventing any drying window from opening.
Average humidity over the last 7 days is 77% and forecast to remain 84–93% through midweek, severely limiting evaporative drying.
Normally a strong drying advantage, but irrelevant when rain is actively falling and humidity remains above 80%.
34.6mm over 28 days with frequent wetting events means the sandstone has had limited opportunity to dry out internally.
Recommendations
3
- Do not visit Callerhues until at least August 24th — a minimum of two full dry days after the last forecast rain on August 21st is needed.
- Monitor conditions closely: if August 22nd and 23rd are genuinely dry with low humidity, an assess-conditions visit on August 24th may be feasible.
- Consider non-porous alternatives such as Whin Sill crags (e.g. Crag Lough, Peel Crag) which can be climbed more safely in damp conditions.
Do Not Climb
75%
65 days ago
Today has seen 2mm of rain with high humidity (88%), breaking a 6-day dry spell, and the forecast shows further rain over the next three days totalling ~17.5mm. Although the preceding dry spell (Aug 10–15) would have dried the rock well, today's rain and the incoming wet spell mean conditions are unsuitable now and will remain poor until at least August 21.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Callerhues sits at 323m on exposed moorland with a SW aspect, so it catches wind and sun effectively — this is one of the fastest-drying Fell Sandstone crags, but even so the incoming multi-day wet spell will saturate the rock thoroughly.
- The 40-minute approach via the Pennine Way crosses notoriously boggy ground that will be significantly worse after the forecast rain — wellies or gaiters advisable even when the crag itself is dry.
- Routes here blur trad and highball bouldering with bold, committing character — any residual moisture makes the consequences of hold failure or a slip especially serious given the lack of reliable protection on many lines.
- Permission from Blakelaw Farm is required and no dogs are allowed — plan ahead and confirm access before making the walk in.
Warnings
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- Do not climb on Fell Sandstone that has not had at least two full dry days — internal moisture causes hold breakage and permanent route damage even when the surface appears dry.
- The bold, highball nature of many Callerhues routes means a slip on damp rock could result in a serious ground fall with minimal protection.
Reasoning
Today's 2mm of rain on already-humid air (88%) has wetted the rock surface, ending the 6-day dry spell that had likely brought the crag close to fully dry condition after the 1.9mm on August 9.
The excellent 6-day drying window (Aug 10–15) with warm temperatures up to 27°C and moderate winds would have thoroughly dried the rock, but today's rain resets the clock and the forecast wet spell (17.5mm over Aug 17–20) will re-saturate the sandstone before any meaningful drying can occur.
The cumulative ~19.5mm of rain from today through August 20, combined with high humidity (83–94%), will push pore saturation well above the threshold where compressive strength loss becomes significant — hold breakage risk is real on these bold, unprotected lines.
Mid-August is typically a reasonable window for Fell Sandstone, but this unsettled spell with below-average temperatures (11–17°C) and high humidity will slow drying considerably compared to the warm spell just ended.
Contributing Factors
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2mm today followed by 4.7mm, 3.8mm, and 9mm over the next three days will keep the rock saturated through at least August 20.
Humidity averaging 83–94% over the next four days severely limits evaporative drying even between showers.
The hilltop exposure and south-westerly aspect maximise wind and sun contact, meaning the crag will dry faster than most Fell Sandstone once the rain stops.
Winds of 12–28 km/h persist through the forecast period, which will aid drying once precipitation ceases.
The warm dry period Aug 10–15 had fully dried the rock, but today's rain negates this benefit and the slate is effectively reset.
Forecast highs of only 11–17°C with a minimum of 2°C on Aug 21 will slow drying compared to the preceding warm spell.
Recommendations
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- Wait until at least August 22 — the rock needs a minimum of two full dry days after the last rain (forecast to end Aug 20–21) before climbing is responsible.
- Check the ground at the crag base on arrival: if the soil or peat is still damp, the sandstone almost certainly retains internal moisture despite any surface drying.
- Consider the boggy approach conditions — the Pennine Way section will be very wet after this rain spell, so allow extra time and bring appropriate footwear.
Climbing Outlook