Condition Analysis
AI-powered assessment using site data and 14-day weather history
Caley Crags has received repeated light rain over the past week (7.1mm in 7 days across multiple events), with the most recent precipitation today (0.3mm) and 2.1mm yesterday. The NW-facing aspect, woodland setting, and lack of consecutive dry days mean the gritstone is very unlikely to have dried adequately, and further rain is forecast tomorrow and Tuesday.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly reduces airflow and direct sunlight at rock level, trapping moisture and extending drying times well beyond open moorland gritstone venues.
- The Roadside Boulders sit lower in the trees and tend to stay damper longer than the Main Crag higher up the hill, which catches slightly more breeze.
- The NW aspect means the crag receives almost no direct sun until late afternoon/evening in spring, severely limiting solar drying — this venue is genuinely best reserved for hot summer conditions.
- Caley's classic slab problems and delicate holds are particularly vulnerable to wet-rock damage; the tenuous friction-dependent nature of many problems makes even marginal dampness a safety and conservation concern.
Warnings
3
- Gritstone that appears surface-dry in woodland settings can still be significantly weakened internally — do not rely on touch tests alone at Caley.
- Climbing on damp gritstone at Caley risks permanent damage to the delicate slab holds and friction-dependent problems that define this venue.
- Check BMC RAD for any bird nesting restrictions before visiting — peregrine and raven restrictions may apply at nearby crags during April.
Reasoning
Multiple rain events over the past two weeks (40.1mm in 28 days) with no consecutive dry days — the gritstone is almost certainly retaining significant internal moisture despite any surface drying.
The NW aspect and sheltered woodland setting severely limit solar drying; moderate winds from the SW/W provide some help but cannot compensate for repeated wetting events and high humidity (72% average over 7 days).
With repeated wetting and no sustained dry period, the gritstone is at elevated risk of strength loss and grain loosening — climbing on holds that appear dry but are internally saturated could cause permanent breakage.
Early April in Yorkshire means cool temperatures (8.4°C average) and short effective drying windows; the crag is still in its marginal late-winter/early-spring condition phase and won't reliably dry quickly until warmer, longer days arrive.
Contributing Factors
8
Rain fell on 5 of the last 7 days (totalling 7.1mm) with 0.3mm today, meaning there have been zero consecutive fully dry days for the rock to begin meaningful drying.
The north-west facing aspect receives negligible direct sun in spring, drastically slowing evaporative drying compared to south-facing venues.
The classic woodland setting traps humid air around the boulders and blocks what little sun might reach them, further prolonging drying times.
Partial wind exposure with moderate SW/W winds (17–42 km/h recently) provides some drying benefit, but is insufficient to overcome the repeated wetting and sheltered tree cover.
Average temperatures of 8.4°C over the past week are too cool to drive rapid evaporation from porous gritstone.
Average humidity of 72% over the past 7 days limits the moisture gradient needed for effective evaporative drying.
40.1mm over 28 days with frequent wetting events means the rock has been in a near-continuously damp state with no opportunity for deep drying.
1.9mm forecast tomorrow and 3.1mm on Tuesday will re-wet any surface drying that occurs today, perpetuating the cycle.
Recommendations
3
- Do not climb at Caley today — the gritstone has had zero consecutive dry days and the rock will be internally damp despite any surface appearance.
- Wait for at least 48–72 hours of genuinely dry weather with low humidity before visiting; the current forecast does not offer this window until Thursday at the earliest.
- If you need to climb this week, consider a non-porous alternative such as limestone or whinstone where structural damage from dampness is not a concern.
Previous Analyses
Do Not Climb
85%
2 days ago
Caley Crags has received rain today (1.8mm) on top of 3.7mm yesterday and repeated light precipitation throughout the past week, with zero consecutive dry days. The NW-facing woodland setting at 200m will retain moisture extensively, and the gritstone will not have had adequate drying time.
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 direct sun, dramatically slowing drying compared to open moorland gritstone venues.
- The Roadside Boulders sit lower and closer to the road with tree cover overhead, meaning they dry even more slowly than the Main Crag higher up the hill.
- NW aspect means the crag receives no meaningful direct sun until late afternoon/evening in summer — in early April, solar drying contribution is negligible.
- Caley's renowned slab problems and delicate holds are especially vulnerable to wet-rock damage; the tenuous friction-dependent climbing makes even slight dampness both dangerous and destructive.
Warnings
3
- Climbing on wet gritstone causes permanent, irreversible damage to holds — Caley's delicate slab problems are especially vulnerable.
- The rock surface may appear dry in places while remaining saturated internally; do not be fooled by surface appearance.
- Freeze-thaw risk exists over the coming nights with sub-zero forecasts on saturated rock — this causes cumulative structural damage.
Reasoning
Rain today (1.8mm), yesterday (3.7mm), and frequent light showers over the past week (6.5mm in 7 days, 42.2mm in 28 days) mean the gritstone is almost certainly saturated or near-saturated internally, despite potentially appearing surface-dry in places.
With zero consecutive dry days, NW aspect providing minimal solar input in early spring, and the sheltered woodland setting reducing wind effect, there has been no meaningful drying window — even the brief dry spell on April 6–8 was interrupted before full drying could occur.
Gritstone at even ~1% saturation suffers significant strength loss; the repeated wetting cycles over the past month without adequate drying periods mean hold breakage risk is elevated, particularly on Caley's delicate slab features.
Early April at 200m with overnight lows near or below freezing (min -0.2°C forecast for April 14) introduces freeze-thaw risk on saturated rock, compounding structural concerns from the prolonged wet spring period.
Contributing Factors
7
1.8mm today following 3.7mm yesterday means the rock surface is freshly wet with no drying window.
There have been no consecutive dry days, so drying has not even begun — the minimum 48-hour rule for porous rock is far from met.
6.5mm over the past 7 days and 42.2mm over 28 days indicate a prolonged wet period keeping the rock chronically saturated.
The NW-facing, tree-sheltered setting receives minimal direct sun in early spring and reduced wind, severely limiting evaporative drying.
Today's 29 km/h SW wind provides some airflow but the partial shelter of the woodland canopy limits its drying benefit, and it cannot compensate for ongoing rain.
Overnight lows near 0°C (forecast -0.2°C on April 14) on saturated rock create freeze-thaw damage potential above the critical 60% pore saturation threshold.
Early April is a transitional period with unpredictable weather, cool temperatures averaging 8.5°C, and insufficient warmth to drive rapid drying.
Recommendations
3
- Do not climb at Caley today — the rock is wet from today's rain and has had no drying period after repeated recent precipitation.
- Wait for at least 48–72 hours of completely dry weather with temperatures above 10°C before visiting; given the woodland setting and NW aspect, err towards the longer end.
- If desperate to climb, consider a south-facing, open, non-porous venue such as a limestone sport crag where wet-rock ethics do not apply in the same way.
Do Not Climb
75%
3 days ago
Caley Crags received 2.5mm of rain today and has had repeated light precipitation events over the past week, with no consecutive dry days accumulated. The NW-facing woodland setting, moderate humidity, and cool spring temperatures mean the gritstone is very likely still holding moisture internally despite any surface drying between showers.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly slows drying — the tree canopy traps humidity and blocks what little direct sun the NW aspect receives, meaning the rock retains moisture far longer than open gritstone edges.
- The Roadside Boulders sit lower in the hillside and are more sheltered, so they dry slower than the Main Crag higher up; the Main Crag gets slightly more airflow but is still predominantly shaded.
- Caley's famous slabs and delicate holds are particularly vulnerable to wet-rock damage — tenuous smears and friction-dependent moves on weakened gritstone are both an ethical and safety concern.
- Seepage and ground moisture around the woodland base of the boulders is a reliable indicator of internal rock moisture — if the leaf litter and soil are damp, the rock almost certainly is too.
Warnings
2
- Climbing on wet gritstone at Caley risks permanent damage to the delicate slab holds and friction-dependent problems that define this venue.
- Overnight frost forecast on April 13–14 (lows of 0.4°C and -0.6°C) could cause freeze-thaw damage if the rock remains internally saturated.
Reasoning
With 2.5mm of rain today and repeated light showers on April 9, 10, and earlier in the week (totalling ~5.7mm in the last 7 days), the gritstone is very likely wet internally despite any brief surface drying between events.
Although there have been reasonable westerly winds (29–42 km/h) over recent days, the NW aspect and woodland shelter at Caley substantially reduce effective drying, and the rock has had zero consecutive fully dry days to recover.
Repeated wetting without adequate drying keeps the gritstone near its weakened state — climbing on friction-dependent slab problems risks both hold breakage and accelerated surface erosion on this heavily-used venue.
Early April in Yorkshire at 200m means cool temperatures (averaging ~8°C), with overnight lows near or below freezing forecast in coming days, which further slows drying and introduces mild freeze-thaw risk on any residual internal moisture.
Contributing Factors
7
2.5mm of rain today means the rock surface is actively wet or freshly wetted, resetting any drying progress from recent dry spells.
The last week has seen rain on most days (April 3, 4, 5, 9, 10, 11), preventing the gritstone from achieving the minimum 48-hour dry window needed.
The north-west facing, tree-covered setting receives minimal direct sunlight and traps humidity, dramatically slowing evaporation from the porous gritstone.
Southerly winds at ~30 km/h today provide some drying assistance, though the woodland canopy limits wind penetration to the rock surfaces.
Average temperatures around 8–10°C provide only modest evaporative drive, and overnight lows near freezing further limit drying capacity.
Today's 63% humidity is reasonable for drying but insufficient to overcome the combined effect of fresh rain and sheltered aspect.
Nearly 40mm over the past 28 days with frequent wetting events means the gritstone has been repeatedly saturated without adequate recovery time.
Recommendations
3
- Do not climb at Caley today — the rock received rain today and has had no meaningful dry period; wait for at least 48 hours of dry, breezy weather before visiting.
- Check the soil and leaf litter at the base of the boulders as a proxy for internal rock moisture — if the ground is damp, the gritstone certainly is too.
- Consider switching to a non-porous alternative such as Almscliff (whinstone top) or limestone venues in the Dales which can be climbed when damp without ethical concerns.
Do Not Climb
45%
4 days ago
Despite a promising dry spell from April 6–8 with warm temperatures, light rain returned on April 9 (0.7mm) and today (0.1mm), resetting the drying clock on this NW-facing woodland crag. The combination of high recent cumulative rainfall (41mm in 28 days), the sheltered woodland setting, and the NW aspect means internal moisture levels are likely still elevated even where surfaces may appear dry.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly reduces airflow at rock level, trapping humid air and slowing evaporation despite moderate wind readings at exposed weather stations.
- The Roadside Boulders sit lower and closer to the road in denser tree cover, drying more slowly than The Main Crag higher up the hillside where there is slightly better air circulation.
- NW-facing aspect means very limited direct sun even on clear days — in early April the sun angle is still low and the crag receives almost no direct solar heating to drive moisture out.
- Known seepage issues on several popular problems, particularly on the slabbier faces where water tracks through horizontal breaks and can persist for days after rain.
Warnings
2
- Caley's delicate slab problems with small crystalline holds are particularly vulnerable to breakage when gritstone is internally damp — damage is irreversible.
- Surface-dry gritstone can still be critically weakened internally; do not rely on touch alone to judge conditions at this sheltered woodland crag.
Reasoning
The 11.9mm event on March 24 followed by repeated small rain events (totalling ~14mm since March 25) means the rock has had no sustained dry period long enough to fully dry internally, despite brief warm spells.
The three dry days April 6–8 with temperatures up to 20°C would have helped surface drying considerably, but the NW aspect and woodland shelter limit this benefit, and the 0.7mm on April 9 has re-wetted surfaces before internal moisture could fully dissipate.
With 41mm of rain over 28 days and no extended dry period, internal moisture content is likely above the critical threshold where gritstone experiences significant strength loss, posing hold breakage risk especially on Caley's delicate slab holds.
Early April in Yorkshire is still a transitional period with cool average temperatures (~8°C) that slow evaporation, and overnight lows near or below freezing adding minor freeze-thaw concerns for saturated rock.
Contributing Factors
7
Rain on April 5 (2.2mm), April 9 (0.7mm), and today (0.1mm) has kept re-wetting surfaces and preventing a clean drying window from establishing.
The NW-facing aspect receives negligible direct sunlight in early April, severely limiting solar-driven evaporation from the rock surface.
The classic woodland setting traps humidity around the boulders and blocks wind at rock level, significantly reducing effective drying rates.
Three consecutive dry days peaking at 20.3°C on April 8 would have driven meaningful surface drying and some internal moisture reduction.
Today's 39 km/h SW wind and low 63% humidity are helpful for surface drying, though the partial shelter limits how much reaches the rock.
Over 41mm in 28 days with no sustained dry window means the rock's pore network has been repeatedly recharged with moisture throughout the period.
The 7-day average of 8.3°C limits evaporation rates, and overnight lows near 1–3°C further slow the drying process.
Recommendations
3
- Wait for at least 48 hours of confirmed dry weather with temperatures above 10°C before visiting — the forecast does not currently offer this window.
- 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 other venues with better aspect (south-facing) or non-porous rock types until a sustained dry spell arrives.
Marginal — Assess Conditions
62%
5 days ago
Four consecutive dry days including yesterday's warm spell (20°C) with moderate wind have provided reasonable drying, but the NW aspect, woodland setting, and preceding wet period (53.9mm in 28 days with frequent light showers through early April) mean internal moisture may linger. Climbers should visually and physically assess rock conditions on arrival before committing to climb.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly reduces airflow and direct sunlight at the Roadside Boulders, meaning these will dry considerably 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 — even yesterday's 20°C warmth would have had limited direct drying effect on the rock face itself.
- Seepage is common at Caley after wet periods, particularly on the Main Crag where water percolates through the hillside above; check for dark patches and damp streaks before climbing.
- The classic tenuous slabs and delicate holds at Caley are especially vulnerable to grain loosening when damp — even marginal moisture makes these features dangerous and risks permanent damage.
Warnings
2
- Do not climb on any rock that feels cool and damp to the touch — surface-dry gritstone can still be dangerously weakened internally after the recent wet period.
- Caley's delicate slab holds are particularly vulnerable to irreversible breakage if climbed on while damp; err strongly on the side of caution.
Reasoning
The last significant rain was 2.2mm on April 5th (4 days ago), but repeated light showers through late March and early April have kept the rock periodically wetted, and the high 28-day total of 53.9mm suggests the gritstone may retain internal moisture despite surface drying.
Four dry days with yesterday reaching 20°C and moderate winds today (31.7 km/h W) have provided decent drying conditions, but the NW aspect and sheltered woodland setting significantly limit evaporation, meaning drying has been slower than these temperatures would suggest for an open, south-facing crag.
Gritstone is highly susceptible to grain loosening when damp, and the repeated wetting cycles through March into April mean holds — particularly on Caley's famous delicate slabs — could still be weakened internally even if surfaces appear dry.
Early April in Yorkshire is transitional with improving but unreliable conditions; overnight temperatures dropping to 1-5°C slow drying, and the high overnight humidity (84-87%) means dew formation may be re-wetting surfaces each morning.
Contributing Factors
7
No measurable rain since April 5th (2.2mm), giving the rock four full days of drying time which approaches the minimum guideline for light rain.
Yesterday reached 20.3°C with low afternoon humidity (47-54%), providing the best single drying day in weeks.
The north-west facing aspect receives minimal direct sun, and the woodland setting at the Roadside Boulders traps humid air and blocks wind, dramatically slowing evaporation.
Frequent light showers from March 24 through April 5 (multiple days with 0.5-4.3mm) kept the rock periodically re-saturated, preventing deep drying between events.
Overnight humidity consistently 82-87% with dew point conditions likely causing surface re-wetting each night, partially negating daytime drying.
Today's 31.7 km/h westerly wind will help move moist air from the rock surface, aiding continued drying through the day.
53.9mm over 28 days reflects a wet late-winter/early-spring pattern that can leave porous gritstone with elevated baseline moisture content even after short dry spells.
Recommendations
3
- Perform a thorough touch test on multiple areas of rock — particularly lower sections and shaded faces — before climbing; if any dampness is detected, do not climb.
- Favour the Main Crag higher up the hill over the Roadside Boulders, as it has slightly better exposure to wind and any late-afternoon sun.
- Avoid any problems with visible seepage, dark patches, or moss-covered sections, and consider returning on a dry afternoon later in the week if conditions feel marginal today.
Marginal — Assess Conditions
62%
6 days ago
Three full dry days following light rain on April 5th (2.2mm), with two warm sunny days (April 7–8 reaching 17–19°C), suggest surface conditions are likely dry, but the NW aspect, woodland setting, and persistent background moisture from a wet preceding month (54.8mm in 28 days) mean internal dampness cannot be ruled out. Climbers should visually and physically assess rock conditions on arrival before committing to climb.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting traps humidity and limits airflow around the Roadside Boulders especially, significantly slowing drying compared to open moorland gritstone venues.
- The NW aspect means direct sun only reaches the crag on long summer evenings; in early April the sun angle is still low and drying relies primarily on ambient temperature and wind rather than solar heating.
- The Main Crag higher up the hill may benefit from slightly better wind exposure and drainage compared to the sheltered Roadside Boulders — conditions can vary significantly between the two areas.
- Seepage and moss are common at Caley, particularly on the slabs and lower sections; these areas will retain moisture long after the more overhanging problems have dried.
Warnings
2
- Do not climb if any dampness is detected on the rock surface or if the ground beneath boulders is wet — gritstone loses significant strength at even 1% saturation.
- The surface may appear dry while the interior remains damp after the wet March; test edges and holds gently before committing to harder moves.
Reasoning
The last significant rain was 2.2mm on April 5th, giving approximately 3 dry days, but the preceding weeks saw frequent light-to-moderate rain totalling 54.8mm over 28 days, meaning the rock's pore network has been repeatedly recharged and background saturation levels may still be elevated.
Two excellent drying days on April 6–7 (warm, low humidity dropping to 41%, moderate wind) and today's warm conditions (19.6°C) have provided reasonable surface drying, but NW aspect and woodland shelter substantially reduce effective evaporation compared to exposed south-facing crags.
The repeated wetting-drying cycles through March and the cumulative 54.8mm over 28 days mean gritstone grain bonds may be weakened even if the surface feels dry; particular caution is warranted on delicate slopers and fragile edges.
Early April is transitional — improving temperatures help but overnight lows near 1–4°C and high overnight humidity (80–90%) cause condensation that re-wets surfaces and slows the drying process each night.
Contributing Factors
8
No rain since April 5th (2.2mm), providing approximately 72 hours of drying time which meets the minimum threshold for light rain in reasonable conditions.
Today's forecast high of 19.6°C is excellent for evaporation and significantly above the seasonal average, boosting drying potential.
The north-west facing aspect receives minimal direct sun in early April, meaning drying relies on ambient warmth and wind rather than direct solar heating of the rock surface.
The sheltered woodland environment at Caley reduces airflow and traps humidity around the boulders, significantly slowing drying compared to open gritstone edges.
Overnight humidity consistently reaching 80–91% with lows near 2–4°C causes condensation on rock surfaces, partially reversing daytime drying gains.
54.8mm of rain over the past 28 days with frequent wetting events means the rock has been repeatedly saturated, and deep pore moisture may persist despite surface drying.
Wind speeds of 40–48 km/h on April 3–5 and moderate winds since have helped move moist air away from rock surfaces and accelerate drying.
Humidity dropped to 41% yesterday afternoon with 17°C and moderate wind, providing an extended period of excellent evaporative conditions.
Recommendations
3
- Check the ground at the base of boulders — if soil or leaf litter is damp, the rock is very likely still holding internal moisture and you should not climb.
- Prioritise the Main Crag's steeper, more exposed problems over the sheltered Roadside Boulders, as the higher area will have dried more effectively.
- Avoid slabs, seepage-prone faces, and any areas with visible moss or damp patches — these will be the last to dry and present the greatest risk of hold damage.
Do Not Climb
45%
8 days ago
Caley Crags received 2.2mm of scattered rain throughout yesterday (April 5th), and only one dry day has elapsed since. Given the NW aspect, woodland setting, and high background moisture from 54.8mm over the past 28 days, the gritstone is very likely still holding internal moisture despite any surface drying today.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly slows drying — the tree canopy reduces airflow and traps humidity around the boulders, particularly at the Roadside Boulders which sit lower and more sheltered than The Main Crag.
- The NW aspect means these boulders receive almost no direct sun until late afternoon/evening in spring, so solar drying contribution is minimal at this time of year.
- The split between Roadside Boulders (lower, more sheltered, slower to dry) and Main Crag (higher, slightly more exposed) means conditions can vary significantly across the venue — Main Crag may dry faster.
- Caley's famous tenuous slabs and delicate holds are especially vulnerable to damage when the gritstone is internally damp — these style of problems demand conservative ethics around moisture.
Warnings
2
- Do not climb today — the gritstone is almost certainly still damp internally after yesterday's rain, and climbing risks permanent hold damage on Caley's delicate problems.
- The prolonged wet March (54.8mm in 28 days) means deep moisture levels will be elevated even when surfaces appear dry — surface dryness is not a reliable indicator of safety at this time.
Reasoning
With 2.2mm of rain spread across yesterday and only one dry day since, combined with 54.8mm over the past 28 days keeping background saturation elevated, the gritstone is very likely still damp internally despite any surface drying.
Today is dry with moderate temperatures (13°C) and low-ish humidity (69%), but the south wind at only 14.8 km/h provides limited drying benefit to this NW-facing, woodland-sheltered crag — one day is insufficient drying time after yesterday's rain on already-saturated rock.
The gritstone will have reduced compressive strength from persistent moisture over recent weeks, and climbing on subtly damp holds risks permanent grain loosening and hold breakage, particularly on the delicate slab problems Caley is known for.
Early April in Yorkshire still presents cool overnight temperatures (1°C last night) and high background humidity, meaning drying rates remain slow; the woodland canopy is leafing out, further reducing airflow around the boulders.
Contributing Factors
7
2.2mm of rain fell across much of April 5th, with the last trace at 18:00, giving less than 24 hours of drying time.
54.8mm over the past 28 days with frequent wet spells means the gritstone has had little opportunity to dry out fully at depth.
The NW-facing aspect receives negligible direct sun in early April, severely limiting solar-assisted evaporation from the rock surface.
The classic woodland setting traps humid air around the boulders and blocks wind, significantly reducing drying rates compared to exposed crags.
Today is forecast dry at 13.2°C with 69% humidity and light southerly winds, which will begin the drying process.
Gritstone requires a minimum of 24–48 hours of good drying conditions after light rain, and significantly more given the saturated background state — only one day is insufficient.
Last night dropped to 1°C with humidity rising above 80%, likely causing condensation on rock surfaces and halting any drying progress overnight.
Recommendations
3
- Wait at least until April 8th after two warm, dry days (17°C+ forecast) before considering a visit, and even then assess conditions carefully on arrival.
- If visiting, check the ground at the base of boulders — if soil or leaf litter is damp, the rock is certainly still wet internally and should not be climbed.
- Prioritise The Main Crag over the Roadside Boulders as it sits higher with slightly better exposure, but still apply the touch-and-wait test before committing to any problem.
Do Not Climb
60%
9 days ago
Caley Crags has received frequent light-to-moderate rainfall over the past two weeks with no meaningful dry spell, and today itself has seen 2mm of rain. The NW-facing woodland setting retains moisture well, and despite strong winds, the rock is very likely still damp internally — conditions are not suitable for climbing today.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly reduces airflow at rock level and traps humidity, meaning the strong winds recorded at weather stations may not translate to effective drying at the boulders themselves.
- The Roadside Boulders sit lower and in denser tree cover, so they dry more slowly than The Main Crag higher up the hill — even when the upper crag feels dry, the lower problems may still be damp.
- NW-facing aspect means very limited direct sun in early spring, with the low sun angle providing almost no warming to the rock faces during March and early April.
- Gritstone slabs and tenuous holds at Caley are particularly vulnerable to grain loosening when wet — the bold slab problems that define this venue should be treated with extra caution regarding moisture.
Warnings
2
- Do not climb today — rain has fallen and the gritstone will be wet; climbing risks permanent hold damage on Caley's delicate features.
- Overnight frost on saturated rock (forecast -0.2°C on April 6th) poses freeze-thaw damage risk — avoid climbing early morning even if the surface looks dry.
Reasoning
With 2mm of rain today, 7.3mm in the last 7 days spread across multiple events, and 54.6mm over 28 days with no consecutive dry spell longer than a few days, the gritstone at Caley is almost certainly holding significant internal moisture despite any surface drying.
Strong westerly winds today (42.5 km/h) and moderate temperatures help surface evaporation, but the NW aspect and woodland shelter limit effective drying, and the absence of any sustained dry period means the rock has not had opportunity to dry through — each small rain event re-saturates the surface before the interior can release moisture.
Repeated wetting over the past month without adequate drying means the gritstone is likely above the critical ~1% saturation threshold where significant strength loss begins, posing real risk of hold breakage particularly on the delicate slab features Caley is known for.
Early April at 200m with NW aspect means cool conditions with limited solar gain; overnight temperatures dipping near or below freezing (forecast -0.2°C tomorrow morning) introduce freeze-thaw risk on saturated rock, adding cumulative structural damage concern.
Contributing Factors
7
2mm rain today with additional light precipitation on April 3rd (0.5mm) and April 4th (0.9mm) means the rock has had zero consecutive fully dry days and no chance to begin proper drying.
54.6mm over 28 days with rain falling on the majority of days means the rock has been in a state of near-continuous saturation throughout March.
The NW-facing woodland setting receives minimal direct sun in early spring and shelters the rock from the full force of drying winds, dramatically slowing evaporation.
42.5 km/h westerly wind aids surface evaporation, though its effect is substantially reduced by the woodland canopy around the boulders.
Temperatures around 8-9°C are adequate for some evaporation but far from the warm conditions needed for rapid drying of porous gritstone.
Tomorrow's forecast minimum of -0.2°C with likely-saturated rock creates freeze-thaw risk, potentially causing cumulative structural damage.
Humidity at 66% is the lowest in over a week and supports evaporation, but this benefit is offset by today's rain and the woodland microclimate.
Recommendations
3
- Wait for the forecast dry spell — April 7th or 8th look more promising after 2+ dry days with warmer temperatures, but verify conditions on arrival.
- If visiting later this week, prioritise The Main Crag higher up the hill over the Roadside Boulders, as it will dry faster with better air circulation.
- Check the base of the crag for damp ground before climbing — if the soil and leaf litter at the foot of the boulders are moist, the rock interior is almost certainly still wet.
Do Not Climb
70%
10 days ago
Caley Crags has received frequent light-to-moderate rain over the past two weeks (52.5mm in 28 days) with no consecutive dry days established, and today itself has seen 0.8mm of precipitation. The NW-facing woodland setting, high humidity, and lack of a sustained dry window mean the gritstone is very likely still holding internal moisture despite surface appearances.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting significantly slows drying — the tree canopy traps humidity and blocks what little direct sunlight could reach this NW-facing crag, meaning moisture lingers far longer than at open moorland gritstone venues.
- The Roadside Boulders sit lower and closer to road-level drainage, often staying damper than the Main Crag higher up the hill; climbers should check both areas independently.
- Many classic problems here rely on tenuous slab friction and small crystal edges — exactly the hold types most compromised by residual moisture, making Caley particularly unforgiving of marginal conditions.
- Seepage is common on parts of the Main Crag after sustained wet periods, and moss growth in the woodland setting retains moisture against the rock surface for extended periods.
Warnings
2
- Do not climb on gritstone that has not had at least two full dry days — surface-dry rock can still be critically weakened internally, risking irreversible hold breakage.
- Freeze-thaw risk exists with overnight temperatures near 0°C forecast for April 6; saturated rock undergoing freeze-thaw cycles suffers cumulative structural damage.
Reasoning
With 9.5mm in the last 7 days spread across multiple events (including rain today), zero consecutive dry days, and 52.5mm over 28 days, the gritstone is almost certainly retaining significant internal moisture despite potentially appearing dry on the surface.
Although strong SW/W winds (25–48 km/h) have been present recently, Caley's partial wind exposure and NW aspect in a woodland setting severely limit the drying benefit; humidity averaging 77% over the past week further suppresses evaporation.
Gritstone weakens substantially even at low saturation levels, and the repeated wetting cycles over the past month without adequate drying windows mean the rock is likely in a weakened state — climbing risks hold breakage and permanent route damage.
Early April in Yorkshire brings improving but unreliable conditions; overnight lows near or below freezing (−1.0°C on March 26, 0.0°C forecast April 6) combined with residual moisture create ongoing freeze-thaw risk that compounds structural vulnerability.
Contributing Factors
7
9.5mm over the last 7 days across multiple events with no consecutive dry days means the rock has had no opportunity to fully dry.
Zero consecutive dry days to date — the minimum community standard of two full dry days for porous rock has not been met.
The NW-facing aspect receives minimal direct sunlight, and the woodland canopy traps humidity, dramatically slowing evaporation from the gritstone.
Recent strong SW/W winds (30–48 km/h) provide some drying benefit, though the sheltered woodland setting limits their effectiveness at rock level.
Average humidity of 77% over the past week suppresses net evaporation, meaning even wind-driven drying is significantly reduced.
52.5mm over 28 days represents sustained wetting that will have deeply saturated the porous gritstone, requiring an extended dry spell to fully recover.
Overnight temperatures near or below freezing (forecast 0.0°C on April 6) combined with residual internal moisture create a freeze-thaw damage risk.
Recommendations
3
- Wait for the forecast dry spell from April 6–8 before visiting — by April 8, three consecutive dry days with warming temperatures and lower humidity should provide a much better window.
- If you do visit, check the ground at the crag base: if the soil or leaf litter is damp, the rock is almost certainly still wet internally and should not be climbed.
- Focus any session on the Main Crag higher up the hill rather than the Roadside Boulders, as the higher position drains and dries marginally faster.
Do Not Climb
70%
11 days ago
Caley Crags has received frequent light-to-moderate rain over the past two weeks (55mm in 28 days) with no meaningful dry spell, and today itself saw 0.9mm of precipitation. The NW-facing woodland setting, high humidity, and lack of direct sun make adequate drying very unlikely despite some strong winds.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Caley's woodland setting traps moisture and reduces airflow at boulder level, meaning the strong SW winds recorded recently will have had less drying effect on the lower Roadside Boulders than the exposed Main Crag higher up the hill.
- The NW aspect means virtually no direct sun reaches the rock faces during March–April, so drying relies almost entirely on wind and ambient temperature — both of which have been only moderate.
- Caley's famous slabs and delicate holds are particularly vulnerable to wet-rock damage; grain loosening on these friction-dependent problems would cause irreversible degradation.
- Seepage and moss are common on many of the boulders, especially on the north-facing sides and in the shaded woodland areas, and these will be holding moisture from the repeated recent rainfall events.
Warnings
2
- Today's rain (0.9mm) combined with repeated wetting events over the past two weeks means the gritstone is almost certainly damp internally — do not be misled by any surface dryness.
- Overnight lows near or below freezing (e.g. -1.0°C on March 26, -0.3°C forecast April 6) combined with saturated rock create active freeze-thaw damage risk.
Reasoning
With 9.7mm in the last 7 days spread across multiple events (most recently 0.9mm today and 0.7mm yesterday), and 55mm over 28 days with no dry spell longer than about 6 days, the gritstone is very likely saturated internally despite any surface drying.
Although there have been strong SW/W winds (25–42 km/h) in recent days which would help surface evaporation, the NW aspect and woodland canopy severely limit both solar heating and wind penetration to the rock, meaning drying has been far slower than the wind data alone would suggest.
Gritstone that has been repeatedly wetted over weeks without adequate drying is at significant risk of grain loosening and hold breakage — climbing on Caley's delicate friction problems in this state could cause permanent damage.
Early April in Yorkshire is a transitional period with cool temperatures (averaging ~7.5°C), still-high humidity, and limited solar angle — conditions that keep porous gritstone damp for extended periods after winter saturation.
Contributing Factors
7
Rain fell on at least 6 of the last 10 days totalling ~10mm, with no consecutive dry spell long enough to allow internal drying of porous gritstone.
The NW-facing rock receives almost no direct sunlight in early April, removing the most effective drying mechanism for porous stone.
The classic woodland setting at Caley reduces wind penetration and traps humid air around the boulders, significantly slowing evaporative drying.
Sustained winds of 25–42 km/h over the past week will have aided some surface drying, particularly on the more exposed Main Crag.
Average humidity of 77% over the past week limits evaporation rates, meaning even wind-assisted drying is slower than it would be in drier air.
With 55mm over 28 days and a generally wet late winter pattern, the gritstone is likely deeply saturated well beyond the surface layer.
An average of 7.5°C over the last week provides only modest evaporative energy, and overnight lows near or below freezing raise freeze-thaw concerns.
Recommendations
3
- Wait for a sustained dry spell of at least 48–72 hours with lower humidity before visiting — the forecast suggests April 6–7 may offer the first realistic window worth assessing.
- If visiting, check the ground at the base of boulders: if soil and leaf litter are damp, the rock is almost certainly still wet internally regardless of surface appearance.
- Prioritise the more exposed and elevated Main Crag over the sheltered Roadside Boulders, as the upper area will have benefited more from recent winds.
Climbing Outlook