Condition Analysis
AI-powered assessment using site data and 14-day weather history
The rock had five fully dry days (Aug 21–25) after 8.8mm on Aug 20, which in summer warmth should have allowed reasonable drying, but today's trace precipitation and very high overnight humidity may have re-dampened surfaces. With 22.9mm forecast tomorrow and continued heavy rain through the weekend, today's late afternoon offers the only realistic climbing window before a prolonged wet spell.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley is a woodland venue — tree canopy traps humidity and limits airflow, significantly slowing drying compared to open moorland gritstone edges.
- The NW aspect means virtually no direct sun reaches the rock, so drying relies almost entirely on wind and ambient temperature rather than solar heating.
- The Roadside Boulders sit lower and closer to the road in denser woodland, and tend to stay damper longer than The Main Crag higher up the hill where wind exposure is slightly better.
- Seepage and ground moisture around the base of problems is common after wet periods — check the soil and leaf litter at the base; if damp, the rock likely still holds internal moisture.
Warnings
2
- Heavy rain (22.9mm) is forecast for tomorrow — do not climb at Caley from Aug 27 onwards until a sustained dry spell allows full drying.
- The woodland canopy can make surfaces feel deceptively dry while the rock retains internal moisture — always check the base soil and lower sections of problems.
Reasoning
After 8.8mm on Aug 20 followed by five dry days with moderate temperatures (17–20°C) and moderate wind, the rock should have substantially dried, but today's trace rain (0.3mm scattered through midday) and very high overnight humidity (88–94%) may have re-wetted surfaces.
The NW aspect and woodland setting severely limit solar drying, but five consecutive dry days with westerly winds at 10–20 km/h and summer temperatures around 18–20°C should have been sufficient for deeper drying of the 8.8mm event, though the sheltered canopy slows the process.
With the bulk of drying from the Aug 20 rain likely complete, structural risk from internal saturation is low, but any surface re-wetting from today's trace precipitation or condensation could still reduce friction and compromise hold integrity on the finer-grained features.
Mid-to-late summer provides the best drying conditions of the year, though the incoming frontal system from tomorrow will reset conditions to fully wet for an extended period.
Contributing Factors
6
Five consecutive dry days (Aug 21–25) after the 8.8mm event on Aug 20 provided good drying opportunity in summer warmth.
The north-west facing, tree-sheltered setting receives virtually no direct sun and limited airflow, substantially slowing evaporation.
Scattered light showers through midday (0.3mm total) and very high overnight humidity (up to 94%) may have dampened rock surfaces.
From roughly 15:00–19:00 today, humidity drops to 54–66% with moderate wind (15–19 km/h), offering a brief drying and climbing window.
22.9mm forecast tomorrow followed by continued rain through Aug 30 (46mm total) will fully saturate the rock for days.
Daytime highs of 18–23°C over the drying period support reasonable evaporation rates even without direct sun.
Recommendations
3
- If climbing today, wait until mid-to-late afternoon (after 15:00) when humidity drops and wind picks up, and physically check the rock and ground for dampness before committing.
- Favour The Main Crag higher up the hill where wind exposure is better and drying will be more advanced than the sheltered Roadside Boulders.
- Do not plan any climbing from tomorrow (Aug 27) through the weekend — the incoming heavy rain will fully saturate the gritstone and require several dry days to recover.
Previous Analyses
Marginal — Assess Conditions
62%
57 days ago
Four consecutive dry days following 8.8mm of rain on Aug 20 and smaller showers on Aug 16–19 have allowed reasonable drying, but the NW aspect, woodland setting, and moderate humidity mean some sheltered areas may still hold residual moisture. Conditions are likely acceptable on exposed faces this afternoon, but a visual check on arrival is essential — and climbers should be aware that a major wet spell (75mm+) arrives from tomorrow onwards.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting traps humidity and shields the rock from direct airflow, significantly slowing drying compared to open moorland gritstone edges.
- The Roadside Boulders sit lower and closer to the road with more tree cover, so they dry more slowly than the higher Main Crag which catches more breeze.
- NW-facing aspect means the crag receives almost no direct sun — drying relies heavily on wind and ambient temperature rather than solar heating.
- Seepage and drainage from the hillside above can keep base sections and cracks damp for days after rain, especially around the Main Crag area.
Warnings
2
- A very heavy wet spell (75mm+) is forecast from Aug 25–29; do not plan any gritstone climbing for the rest of this week after today.
- Ground conditions at the base of the crag are the best field test — if the soil/leaf litter is damp, the rock is still too wet internally.
Reasoning
The most significant rain was 8.8mm on Aug 20, preceded by a cluster of light showers (Aug 16–19 totalling ~5.2mm); four dry days have elapsed since, but the NW aspect and woodland canopy limit evaporative drying.
Moderate westerly-to-easterly winds (10–19 km/h) and temperatures around 17–19°C over the last four days provide decent drying, though the sheltered woodland reduces effective wind speed at the rock face.
With four days of drying after moderate rain, surface gritstone should have regained most strength, but sheltered lower sections and crack systems may retain enough internal moisture to pose hold-breakage risk.
Mid-summer temperatures and daylight hours are favourable for drying, though recent weeks have been cooler than average and the upcoming forecast is very wet — this is the last reasonable window before a prolonged soaking.
Contributing Factors
7
No measurable precipitation since Aug 20 (8.8mm), giving four full days of drying in summer conditions.
The NW-facing crag receives negligible direct sun, so drying depends almost entirely on wind and ambient warmth.
Dense tree cover around the boulders reduces airflow and traps humidity against the rock, slowing evaporation.
Cumulative rainfall of ~14mm over five days (Aug 16–20) means the rock absorbed repeated wettings before the current dry spell began.
Winds of 10–19 km/h and daytime temperatures of 17–19°C over the dry spell provide reasonable evaporative conditions.
Humidity drops to 46–52% this afternoon with decent breeze, creating a good drying window for exposed surfaces.
Over 75mm of rain is forecast from Aug 25–29, which will thoroughly saturate the rock for an extended period.
Recommendations
3
- If climbing today, go in the afternoon when humidity is lowest (46–52%) and check that the rock surface feels completely dry and friction is good before committing to problems.
- Prioritise the higher Main Crag boulders which catch more breeze and drain better than the sheltered Roadside Boulders lower down.
- Avoid any problems with visible damp patches, seepage lines, or green/mossy holds — these indicate persistent internal moisture.
Marginal — Assess Conditions
65%
58 days ago
Three dry days have followed a moderate rain event (8.8mm on Aug 20) and several days of light drizzle, but the NW aspect, woodland setting, and elevated humidity (~74%) mean drying has been slower than ideal. The rock is likely approaching climbable condition on exposed surfaces, but sheltered and lower boulders may still harbour residual moisture.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly retards drying — tree canopy traps humidity and blocks wind from reaching many boulders, especially the Roadside Boulders lower down.
- The NW aspect means the crag receives very limited direct sunlight even in summer, so drying relies heavily on wind and ambient temperature rather than solar heating.
- The Main Crag higher up the hill is more exposed to wind and will have dried faster than the sheltered Roadside Boulders — climbers should prioritise the upper area.
- A major rainfall event (40.8mm) is forecast for Aug 27, followed by another 23.3mm on Aug 28 — conditions will deteriorate sharply later in the week and require extended drying afterwards.
Warnings
2
- Very heavy rain (40.8mm + 23.3mm) is forecast for Aug 27–28 — do not climb during or shortly after this event; extended drying will be required.
- Caley's tenuous slab holds are particularly vulnerable to breakage on internally damp gritstone — err on the side of caution even if surfaces appear dry.
Reasoning
The 8.8mm event on Aug 20 was preceded by four consecutive days of light rain (totalling ~5.2mm from Aug 16–19), meaning the rock entered the heavier rain already partially saturated — three dry days at moderate temperatures (16–19°C) and 72–74% humidity provide marginal drying for a NW-facing, wooded gritstone venue.
Three days of dry weather with moderate westerly-to-easterly winds (9–17 km/h) and temps around 17–19°C provide reasonable but not ideal drying; the NW aspect and woodland canopy reduce effective evaporation, so exposed upper sections should be approaching dry while sheltered lower boulders may lag behind.
Internal moisture from the cumulative wet period (Aug 16–20) may persist in thicker blocks despite surface-dry appearance, posing some risk of hold weakening on delicate slab features — Caley's characteristic tenuous holds are particularly vulnerable.
Mid-summer temperatures and day length are helpful for drying, but the recent below-average temperatures (14°C average over the past week) and elevated humidity (80% average) have underperformed typical August drying potential.
Contributing Factors
7
No precipitation since Aug 20 provides a meaningful drying window, though marginal for the cumulative rainfall that preceded it.
The NW-facing aspect receives minimal direct sun even in summer, making the crag heavily reliant on wind and ambient conditions for drying.
The wooded setting reduces airflow and traps humidity around the boulders, significantly slowing evaporation compared to open moorland gritstone.
Winds of 10–17 km/h and temperatures around 17–19°C provide reasonable drying conditions, though not exceptional.
Average humidity of 72–74% over the past three days limits evaporative potential, particularly in sheltered spots.
Four days of light rain (Aug 16–19) preceded the 8.8mm event on Aug 20, meaning the rock was already partially saturated before the heaviest rain fell.
Over 64mm of rain is forecast for Aug 27–28, which will fully re-saturate the rock and require an extended drying period afterward.
Recommendations
3
- Prioritise the more exposed Main Crag boulders higher up the hill over the sheltered Roadside Boulders, which will have dried more slowly.
- Perform a thorough touch-test on holds before committing — if any dampness is felt, or the ground at the base of boulders is moist, back off.
- Plan sessions for today through Aug 26 at the latest; the major storm arriving Aug 27–28 (64mm+) will close this window and require at least 3–4 days of subsequent drying.
Do Not Climb
40%
59 days ago
Caley Crags received 8.8mm of rain just two days ago (Aug 20), preceded by several days of light but persistent rain, and the NW-facing woodland setting significantly slows drying. With only two dry days elapsed, moderate temperatures, and humidity averaging 80% over the past week, the rock is very likely still damp internally despite potentially appearing surface-dry in places.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting traps humidity and shields the rock from wind and sun, dramatically slowing drying compared to open moorland gritstone venues.
- The NW aspect means the crag receives almost no direct sun, especially on the Main Crag higher up the hill — drying relies almost entirely on wind and ambient temperature.
- The Roadside Boulders sit low and close to the road in dense tree cover, making them the slowest-drying problems on site; the Main Crag higher up may catch slightly more breeze but is still heavily shaded.
- Seepage and ground moisture are common after wet spells — check the soil at the base of boulders as a proxy for internal rock moisture.
Warnings
2
- The rock surface may appear dry while the interior remains saturated — do not rely on visual or touch assessment alone after only two dry days.
- Repeated wetting over the past week increases the risk of hold breakage; even familiar holds may be weaker than usual.
Reasoning
The 8.8mm rainfall on Aug 20, following cumulative light rain on Aug 16–19 (totalling ~5.2mm), means the rock was thoroughly wetted; with only two dry days since, internal moisture is very likely still elevated well above safe levels.
Drying has been slow: the NW aspect receives negligible direct sun, wind has been light-to-moderate (14–17 km/h), humidity has remained around 73–74%, and temperatures have been cool for August (16–18°C) — these conditions collectively suggest inadequate drying time for 8.8mm of rain on porous gritstone.
Gritstone that has been repeatedly wetted over the past week (rain on 5 of the last 7 days) is at elevated risk of grain loosening and hold breakage, even if the surface feels dry to the touch.
Mid-to-late August offers reasonable but not peak drying conditions; the recent cool, humid spell has reduced drying potential well below summer averages.
Contributing Factors
6
8.8mm fell on Aug 20, with an additional 5.2mm across the four preceding days (Aug 16–19), thoroughly saturating the porous gritstone.
Two days of drying is insufficient after ~14mm of rain in 5 days, especially given the unfavourable drying environment at this venue.
The NW-facing, tree-sheltered setting means virtually no direct sun reaches the rock, so drying depends entirely on ambient evaporation which is slow at 73% humidity.
Wind at 14–17 km/h from W and N provides some drying assistance, but the woodland canopy significantly reduces effective airflow at rock level.
Temperatures of 16–18°C are helpful for drying compared to winter, though cooler than the recent hot spell (30°C+ on Aug 12–13).
Humidity has dropped from 87% on Aug 20 to 73% today, which aids surface evaporation, though not enough to compensate for the short drying window.
Recommendations
3
- Wait at least 2–3 more completely dry days before visiting — aim for Aug 25 at the earliest, but check conditions carefully on arrival.
- On arrival, test the soil at the base of the boulders: if the ground is damp or muddy, the rock is almost certainly still wet internally.
- If you do visit, consider non-porous alternatives in the area (e.g. Almscliff's gritstone also needs drying, but Brimham or limestone venues may be drier).
Do Not Climb
35%
60 days ago
Caley Crags received 8.8mm of rain yesterday (Aug 20) followed by only one dry day so far, which is insufficient drying time for this NW-facing woodland gritstone venue. With high recent humidity averaging 80% and moderate temperatures, internal moisture is very likely still present despite any surface drying.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly reduces airflow and sun exposure at the Roadside Boulders, meaning these dry much slower than the more open Main Crag higher up the hill.
- The NW aspect means the crag receives virtually no direct sun until late afternoon/evening, and even then only in summer — drying relies heavily on wind and ambient temperature rather than solar heating.
- Seepage and moss are common on the slab problems and in gullies between boulders; these areas will remain damp long after more exposed faces have dried.
- The recent pattern of repeated light rain events (Aug 16–19) before the heavier 8.8mm on Aug 20 means the rock entered yesterday's rain already partially saturated, extending the required drying time.
Warnings
2
- Do not climb today — the gritstone is almost certainly still saturated internally after 8.8mm of rain yesterday on pre-wetted rock.
- Caley's famous delicate slab problems and thin edges are especially vulnerable to permanent damage from climbing on damp gritstone.
Reasoning
8.8mm of rain fell on Aug 20 on top of a week of repeated light showers (Aug 16–19 totalling ~5.2mm), meaning the rock was pre-saturated before the heaviest event — internal moisture levels are almost certainly still elevated.
Only one dry day has elapsed since significant rain, with moderate temperatures (~16°C), 74% humidity, and light northerly wind at a shaded NW-facing woodland crag — far short of the 48–72+ hours needed after heavy rain on porous gritstone.
Gritstone at this moisture level is at serious risk of hold breakage and grain loosening, particularly on the delicate slab problems and thin edges Caley is famous for.
Mid-summer temperatures are helpful but the current cool spell (15–18°C) combined with high humidity is limiting evaporation rates; no freeze-thaw concern at this time of year.
Contributing Factors
7
8.8mm fell on Aug 20 on already-damp rock, and only one dry day has elapsed since — well short of the 48–72 hour minimum for heavy rain on gritstone.
Repeated light rain from Aug 16–19 (~5.2mm cumulative) meant the rock entered the heavier Aug 20 rain already partially saturated, extending drying time significantly.
The NW-facing aspect receives very little direct sunlight even in summer, so drying depends almost entirely on wind and ambient conditions rather than solar evaporation.
Caley's classic woodland setting traps humid air and blocks wind at the lower Roadside Boulders, substantially slowing evaporation compared to open moorland crags.
Average humidity over the last 7 days is 80%, severely limiting the moisture gradient needed for effective evaporation from the rock surface.
15 km/h wind from the north provides some drying benefit, though partial shelter and the NW aspect limit its effectiveness at the crag face.
Temperatures around 15–18°C are adequate for drying but well below the recent heatwave levels (30°C+) that would accelerate evaporation significantly.
Recommendations
3
- Wait at least another 1–2 full dry days before visiting; the earliest reasonable window is Aug 23 if dry weather holds and humidity drops.
- If you do visit, test the ground at the base of boulders — if soil or leaf litter is damp, the rock is almost certainly still wet internally.
- Prioritise the more exposed Main Crag boulders higher up the hill over the sheltered Roadside Boulders, which will dry last.
Do Not Climb
92%
61 days ago
Caley Crags is currently wet and unsuitable for climbing. Today has seen 4.7mm of rain on top of a persistently damp week (10.1mm in the last 7 days), with high humidity and the NW-facing aspect receiving no direct sun to aid drying. The earliest realistic window would be August 22nd–23rd, but even then conditions should be assessed carefully on arrival.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly slows drying — tree canopy traps humidity and blocks what little sun reaches this NW-facing crag, meaning moisture lingers much longer than at open gritstone edges.
- The Roadside Boulders sit lower in the woodland and tend to stay damper longer than The Main Crag higher up the hill, so check both areas independently.
- Gritstone slabs and delicate friction-dependent problems (a Caley speciality) are especially vulnerable to residual moisture — even surface dampness that wouldn't concern you on steeper rock can cause hold breakage on slabs.
- Seepage and run-off from the hillside above can keep the base of The Main Crag wet for days after rain, particularly after the cumulative rainfall seen this week.
Warnings
2
- Caley's delicate slab problems are especially prone to hold breakage when the gritstone is internally damp — surface-dry appearance is not sufficient.
- Heavy rain (15.4mm) is forecast for August 25th which will reset drying entirely, so any climbing window this week is narrow at best.
Reasoning
With 4.7mm of rain today, 1.8mm yesterday, and 1.6mm the day before — totalling over 10mm in the last week — the gritstone is thoroughly saturated internally despite any brief surface drying between showers.
The NW aspect receives virtually no direct sun, the woodland setting traps humid air, and today's humidity has been above 90% for most of the day, meaning almost no effective drying has occurred and won't begin meaningfully until conditions improve tomorrow at the earliest.
At current saturation levels, gritstone compressive strength is substantially reduced (potentially 30%+), making hold breakage on Caley's characteristically delicate features a serious risk.
Mid-August should offer reasonable drying potential in theory, but this unsettled spell with below-average temperatures (15–17°C) and persistent cloud cover is limiting the seasonal advantage considerably.
Contributing Factors
7
4.7mm of rain today, mostly falling overnight and through the morning, has thoroughly wetted the rock surface and recharged internal moisture.
Over 10mm in the last 7 days across multiple rain events means the gritstone has had no opportunity to dry out internally between showers.
The north-west facing aspect receives minimal direct sunlight, dramatically slowing evaporation compared to south-facing crags.
The sheltered woodland environment reduces airflow at the rock surface and maintains higher local humidity, prolonging drying times significantly.
Humidity has averaged 79% over the past week with today peaking above 95%, severely limiting the evaporative potential needed for drying.
Partial wind exposure with 20+ km/h winds forecast provides some drying assistance, though the woodland canopy reduces its effectiveness at rock level.
Two consecutive dry days forecast for August 22–23 with lower humidity and moderate temperatures could allow meaningful surface drying.
Recommendations
3
- Do not climb at Caley today — the rock is wet from ongoing rain and internally saturated from a week of repeated showers.
- The earliest possible window is the afternoon of August 23rd after two dry days, but visually inspect the rock and check the base of the crag for dampness before committing.
- Consider south-facing gritstone venues instead if you need to climb this week, as they will dry significantly faster than Caley's NW aspect.
Do Not Climb
88%
62 days ago
Caley Crags has received intermittent rain over the past four days (0.8mm on Aug 16, 1.2mm on Aug 17, 1.1mm on Aug 18, and 2.9mm today including a 2.2mm burst this morning), with 18.5mm of heavy rain forecast for tomorrow. The NW-facing woodland setting, high humidity, and lack of direct sun mean the rock is unlikely to be dry now, and conditions will deteriorate significantly after tomorrow's downpour.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting traps moisture and blocks airflow, significantly slowing drying compared to open moorland gritstone edges.
- The Roadside Boulders sit lower and closer to the road in heavier tree cover, and typically retain moisture longer than The Main Crag higher up the hill.
- The NW aspect means virtually no direct sun reaches the rock faces, making Caley one of the slowest-drying gritstone venues in the Wharfedale area.
- Many of Caley's classic problems feature delicate slopers and friction-dependent slabs that are exceptionally sensitive to residual moisture — even slight dampness makes these dangerous and damaging.
Warnings
2
- 18.5mm of rain is forecast for tomorrow (Aug 20), which will thoroughly saturate the gritstone and require extended drying time.
- Caley's friction-dependent slabs and slopers become extremely dangerous when damp — surface-dry appearance can mask dangerous internal moisture in this sheltered woodland setting.
Reasoning
The rock has received repeated light rain events over the past four days (cumulative ~6mm since Aug 16) with high humidity averaging 75–93%, meaning the gritstone will be holding significant internal moisture despite individually small totals.
Although there has been moderate westerly wind (20–27 km/h), the NW-facing aspect and woodland shelter severely limit evaporation, and the persistent high humidity (80%+ overnight, only briefly dropping to ~53% mid-afternoon today) means effective drying has been minimal.
Gritstone that has been repeatedly wetted over four days without a proper drying window will have substantially reduced compressive strength, and climbing on it risks hold breakage and accelerated erosion of Caley's characteristically delicate features.
Late August conditions are deteriorating with shorter days and increasing rainfall frequency; the 18.5mm forecast for tomorrow will reset any drying progress and saturate the rock further.
Contributing Factors
6
Four consecutive days of light rain (Aug 16–19, totalling ~6mm) have kept the rock in a persistently damp state with no meaningful drying window.
18.5mm forecast for Aug 20 will thoroughly saturate the gritstone and reset any partial drying.
The north-west facing aspect receives virtually no direct sun, and the dense woodland setting traps humidity and blocks wind, dramatically slowing evaporation.
Humidity has averaged 75–93% over recent days and nights, severely limiting the rock's ability to shed internal moisture.
Westerly winds of 15–27 km/h provide some drying assistance, but the woodland canopy at Caley significantly reduces effective wind speed at the rock surface.
Daytime temperatures around 17–19°C provide some evaporative capacity, though this is modest and largely offset by the shaded aspect.
Recommendations
3
- Do not climb at Caley today or in the coming days — the rock has been repeatedly wetted and heavy rain is imminent tomorrow.
- After the rain clears on Aug 21, allow a minimum of 48–72 hours of dry weather before visiting; realistically Aug 24 at the earliest for an on-site assessment.
- If visiting later in the week, check the base of boulders for damp ground and perform touch tests on shaded lower sections before committing to any problem.
Do Not Climb
92%
63 days ago
Caley Crags has received rain today (1.8mm) on top of recent showers on the 16th and 17th, and more rain is forecast tomorrow and heavily on the 20th. The gritstone will be wet now and has no realistic drying window in the immediate future; climbing today or in the next two days would risk both hold damage and injury.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly slows drying by reducing airflow and trapping humidity around the boulders, even when open hillside conditions appear dry.
- The NW aspect means the crag receives virtually no direct sun during most of the day, making it one of the slowest-drying gritstone venues in the Leeds area.
- The Roadside Boulders sit lower and closer to the tree canopy than The Main Crag, so they tend to hold moisture longer — check these last if assessing conditions.
- Seepage and moss are common on many of the classic slabs and lower walls, which can remain damp for days after apparently light rainfall.
Warnings
2
- Climbing on wet gritstone causes permanent hold breakage and route damage — Caley's delicate slabs and quirky holds are especially vulnerable.
- The rock surface may appear dry in sheltered spots while remaining saturated internally — do not be deceived by surface appearance alone.
Reasoning
Rain fell overnight and into the early morning today (1.8mm total), following 0.8mm on the 16th and 1.1mm on the 17th in high humidity (93%), meaning the gritstone is currently wet through with no meaningful drying interval.
Despite moderate westerly winds today (~25 km/h), 100% cloud cover, high humidity (73–95%), and the NW aspect with woodland shelter mean evaporation rates are very low and no effective drying has occurred.
With repeated wetting over recent days and no drying window, the gritstone will be at significantly reduced compressive strength — climbing risks hold breakage and permanent route damage.
Mid-August should offer good conditions, but this unsettled spell with cool temperatures (15–17°C) and persistent cloud is producing poor drying conditions atypical for summer.
Contributing Factors
5
1.8mm today on top of 0.8mm (16th), 1.1mm (17th in 93% humidity), and scattered light rain earlier in the week means the rock has been repeatedly wetted with no drying break.
The north-west facing aspect receives minimal direct sunlight and the woodland setting traps moisture, making Caley one of the slowest-drying gritstone venues in the area.
Humidity has been 73–96% today under 100% cloud cover, severely limiting evaporation from the rock surface.
1.6mm is forecast for the 19th and a substantial 8.5mm on the 20th, meaning any partial drying will be immediately reversed.
Winds of 20–25 km/h from the west provide some air movement, but the woodland canopy limits penetration to the rock faces, reducing the drying benefit.
Recommendations
3
- Do not climb at Caley today or in the next few days — the gritstone is wet and more rain is imminent.
- The earliest realistic window for dry conditions is Saturday 22nd or Sunday 23rd, after two full dry days following the heavy rain on the 20th — but check conditions on arrival.
- If you must climb this week, consider a non-porous alternative such as Almscliff (also gritstone and similarly affected) or a limestone venue like Malham or Kilnsey which can be climbed when damp without structural damage.
Do Not Climb
70%
64 days ago
Caley received light rain early this morning (0.5mm) with further showers forecast this evening and tomorrow (5.1mm), all under very high humidity and near-zero wind — conditions are not suitable for climbing today and the outlook for the next few days is poor. The NW aspect and woodland setting mean drying will be slow even when rain stops.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting traps moisture and limits airflow, meaning the Roadside Boulders in particular can stay damp well after the Main Crag higher up begins to dry.
- The NW aspect receives virtually no direct sun until late afternoon/evening in summer, so solar drying is minimal compared to south-facing gritstone edges.
- Many classic problems at Caley rely on friction-dependent slab climbing and delicate holds — even marginal dampness makes these both dangerous and damaging.
- The boulders at ground level sit among vegetation and leaf litter that retain moisture, so checking the ground and base of the rock is a reliable indicator of internal dampness.
Warnings
2
- Climbing on damp gritstone causes permanent hold breakage and route damage — Caley's delicate slab problems are especially vulnerable.
- The rock surface may feel dry in sheltered spots while still being saturated internally; do not be deceived by surface appearance alone.
Reasoning
Rain fell early this morning (0.5mm at midnight), following 2.0mm on Aug 16 and scattered light showers over recent days, meaning the rock has had no meaningful continuous dry period and is likely holding internal moisture despite surface appearances.
Today's wind is exceptionally light (mostly 1–4 km/h) with humidity above 85% for much of the day and 100% cloud cover, so virtually no evaporative drying is occurring — the NW-facing woodland setting compounds this.
Gritstone at Caley is porous Millstone Grit that weakens significantly at low saturation levels; with repeated light wettings and poor drying conditions, internal moisture likely persists and hold breakage risk is elevated.
Mid-August should be favourable for drying, but the current spell of cool, humid, unsettled weather with temperatures only reaching ~19°C negates much of the seasonal advantage.
Contributing Factors
6
Rain this morning (0.5mm) follows 2.0mm yesterday, with no consecutive dry days recorded and further rain forecast tonight and tomorrow.
Humidity has been above 85% for most of today with near-saturated air overnight, effectively halting evaporative drying.
Wind speeds are mostly 1–4 km/h throughout today, far too light to assist drying on a sheltered woodland crag.
The NW-facing, tree-enclosed setting receives minimal direct sun and limited airflow, significantly prolonging drying times.
Temperatures around 17–19°C provide some baseline evaporative potential, though this is largely negated by humidity and lack of wind.
5.1mm forecast for Aug 18 will reset any drying progress, followed by another 6.6mm on Aug 20.
Recommendations
3
- Do not climb at Caley today — the combination of recent rain, high humidity, negligible wind, and more rain incoming means the gritstone is almost certainly damp internally.
- The earliest realistic window may be August 22 or later, assuming the forecast rain on the 18th and 20th falls as predicted and is followed by sustained drying.
- If conditions appear dry on visual inspection later in the week, test the base of the boulders and surrounding ground — if either is damp, the rock is still holding moisture.
Marginal — Assess Conditions
70%
65 days ago
Caley has had an excellent extended dry spell from August 8–15 (8 days, no rain) with warm temperatures peaking above 30°C, which should have thoroughly dried the rock. However, today (Aug 16) has seen 0.6mm of light rain, and the forecast shows further light rain over the coming days, so a visual check on arrival is warranted.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting traps humidity and shields the rock from direct sun and wind, significantly slowing drying compared to open crags.
- The NW aspect means the crag receives very little direct sunlight even in summer, so drying relies heavily on ambient temperature and wind rather than solar heating.
- The Roadside Boulders sit lower and closer to the road with some tree shelter, while The Main Crag higher up the hill may catch slightly more breeze but also more precipitation.
- Seepage and moss are common on many of the slab problems — these retain moisture longer than the steeper arêtes and overhangs, so condition variation across the venue can be significant.
Warnings
2
- Further light rain is forecast for Aug 17–20; do not assume conditions will improve before Aug 21.
- Slab problems at Caley are particularly sensitive to residual moisture — even slightly damp gritstone slabs can be dangerously slippery and structurally compromised.
Reasoning
The extended dry spell from Aug 8–15 (8 consecutive dry days with temperatures up to 33°C) will have thoroughly dried the rock internally, but today's 0.6mm of light rain has re-wetted the surface and potentially begun shallow re-absorption.
The prior 8-day dry spell with high temperatures and moderate westerly winds provided excellent drying conditions even for this shaded NW-facing woodland crag; today's light rain is minor but the NW aspect and tree cover mean even small amounts take longer to clear.
Structural risk is low given the prolonged prior drying period — the rock's internal moisture content should be very low, and today's trace rain is unlikely to have penetrated deeply.
Mid-August is one of the best times of year for Caley, with long days, warm temperatures, and no freeze-thaw risk; the current cooler spell is still well within acceptable summer ranges.
Contributing Factors
6
Eight consecutive dry days (Aug 8–15) with temperatures reaching 33°C will have deeply dried the gritstone, building a substantial moisture deficit.
0.6mm of rain today has re-wetted the rock surface, though this trace amount on well-dried rock should not penetrate deeply.
The north-west facing aspect in a wooded setting receives minimal direct sun, slowing evaporation of today's surface moisture.
Westerly winds around 17–18 km/h provide some drying assistance, partially compensating for the lack of direct sun.
Temperatures around 18–22°C support reasonable evaporation rates even without direct solar heating.
Further light rain is forecast for Aug 17–20, meaning conditions are unlikely to improve in the short term and may worsen.
Recommendations
3
- Visit later today or tomorrow morning and perform a thorough touch-test on multiple surfaces before committing to climb — the rock should feel bone-dry, not cool or clammy.
- Prioritise steeper problems, arêtes, and overhanging faces which shed today's rain fastest; avoid slabs and mossy areas which retain moisture longest.
- Consider postponing to Aug 21 or later when the forecast shows a dry window with lower humidity, allowing proper drying after this week's scattered showers.
Climbing Outlook