Condition Analysis
AI-powered assessment using site data and 14-day weather history
Corby's Crag is currently saturated and unsafe for climbing. The past two weeks have seen nearly 50mm of rain with barely any consecutive dry days, today has already received 4.6mm with more forecast this evening, and the sheltered below-road-level position means the rock will be holding significant internal moisture despite any surface drying.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's below-road-level position channels runoff from the road and surrounding ground onto the rock face, meaning it receives more water than open-air rainfall totals suggest.
- The crag is noted for developing 'scrittle' — loose grit on holds — after wet periods, which persists even when the surface appears dry and requires a prolonged dry spell to clear.
- The sheltered setting with minimal air movement drastically slows evaporation; the crag's own condition notes state a 'long sustained period of dry, windy weather' is needed to properly dry.
- The NW-facing sections will be particularly slow to dry given limited direct sun exposure, while the S-facing sections may appear deceptively dry on the surface while remaining wet internally.
Warnings
3
- Climbing today or in the coming days risks permanent damage to this soft Fell Sandstone crag — holds will be weakened by 30–50% and may break under load.
- The rock surface may appear dry in sheltered patches while remaining dangerously saturated internally; do not be deceived by surface appearance.
- The prolonged wet period means 'scrittle' is very likely present on holds, creating a serious slip hazard even where the rock feels superficially dry.
Reasoning
With 14.6mm in the last 7 days, 49.1mm in 28 days, zero consecutive dry days, and today's 4.6mm of rain, the rock is almost certainly saturated throughout — particularly given the sheltered, below-road position that channels additional runoff.
There has been essentially no meaningful drying window; the last significant dry spell ended around June 12, but only lasted ~1.5 days before 0.8mm on June 15 and 4.6mm today — far too short for this sheltered, porous crag to shed moisture.
The friable, high-porosity Fell Sandstone at Corby's is at serious risk of hold breakage and grain loosening; the prolonged saturation over recent weeks means internal strength reduction is likely near the 30–50% range, making climbing genuinely dangerous.
Early-to-mid June should offer reasonable drying conditions, but this has been an unusually wet spell with below-average temperatures (10.8°C average) and persistently high humidity (80% average), negating the seasonal advantage.
Contributing Factors
6
Nearly 50mm over 28 days with repeated rain events every few days means the rock has had no opportunity to dry internally.
Today received 4.6mm with more rain this evening, so there is no drying clock running at all.
The crag's sheltered, sunken position channels runoff from above and prevents wind-assisted drying, making it one of the slowest-drying venues in Northumberland.
Average humidity of 80% over the past week with today at 90% severely limits evaporative drying potential.
SW winds of 20–28 km/h are forecast for coming days, which would aid drying if rain stops — but the sheltered position limits their effect at crag level.
Every forecast day through June 21 shows further precipitation (0.5–3.6mm), preventing any sustained drying period from beginning.
Recommendations
3
- Do not visit Corby's Crag until at least 48–72 hours of continuous dry, breezy weather have elapsed — which the current forecast does not show until June 22 at the earliest.
- If visiting after a dry spell eventually arrives, check the crag top and base for dampness before committing; if the ground at the base is moist or holds feel gritty ('scrittle'), walk away.
- Consider alternative non-porous venues (e.g. Whinstone crags like Kyloe or the Whin Sill) for the coming week, as sandstone is not appropriate in these conditions.
Previous Analyses
Do Not Climb
92%
2 days ago
Corby's Crag has received repeated rain over the past two weeks (44.8mm in 28 days, 12.1mm in the last 7 days alone) with no meaningful dry spell, and further rain is forecast today and throughout the coming week. The rock will be thoroughly saturated internally despite any surface drying, and the crag's sheltered, below-road-level position means it will retain moisture far longer than other Northumberland venues.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's below-road-level position channels runoff from above onto the rock face, meaning it receives additional water beyond direct rainfall — it can be wet when other local crags are dry.
- The rock here is noted as more friable and porous than typical Northumberland Fell Sandstone, developing 'scrittle' (loose surface grit) after rain that persists even when the surface looks dry.
- The sheltered position with minimal wind penetration dramatically slows evaporation; a long sustained dry spell with wind is needed to properly clear moisture from this crag.
- The NW-facing sections will be especially slow to dry given minimal direct sun, while the S-facing sections may appear deceptively dry on the surface while remaining damp internally.
Warnings
3
- Climbing on saturated Fell Sandstone risks permanent hold breakage and irreversible route damage — this crag's noted friability makes it especially vulnerable.
- The surface may appear dry in sheltered south-facing alcoves while the interior remains saturated; do not be deceived by surface appearance.
- Top-roping is explicitly noted as damaging at this crag on soft Fell Sandstone — avoid entirely when conditions are marginal.
Reasoning
The crag has received rain on 8 of the last 14 days totalling over 26mm, with rain again today (1.1mm) and only two consecutive dry days (June 13–14) in that entire period — the rock is almost certainly saturated internally.
The two dry days on June 13–14 featured decent wind (36 and 18 km/h) but humidity remained 70–77%, and the sheltered below-road position limits wind penetration significantly, so meaningful drying of this porous, friable sandstone would not have occurred in just two days.
With prolonged saturation over weeks, the Fell Sandstone will have lost 30%+ of its compressive strength, and the noted friability of this particular crag means hold breakage and grain loosening are a serious concern.
Early June should offer improving conditions, but this has been an unusually wet spell with below-average temperatures (10.6°C average over the last week), significantly slowing any drying.
Contributing Factors
6
Over 26mm of rain in the last 14 days spread across 8 separate rain days has kept the rock in a near-continuously wetted state with no opportunity for thorough drying.
The longest dry gap in the past two weeks was just two days (June 13–14), far short of the 48–72+ hours of good drying weather needed after heavy cumulative rainfall on porous sandstone.
The crag sits below road level in a sheltered hollow, severely limiting wind-driven evaporation and receiving additional runoff from above, making it one of the slowest-drying venues in Northumberland.
Average humidity over the past week is 78%, with today reaching 80%, which drastically reduces evaporation rate from the rock surface.
Further rain is forecast today (1.1mm) and on each of the next four days (totalling ~11mm), meaning no drying window is available in the near future.
The two dry days featured 18–36 km/h winds which would normally aid drying, but the sheltered position limits wind penetration to the rock face and the window was too brief to make a meaningful difference.
Recommendations
3
- Do not climb at Corby's Crag in current conditions — the rock is saturated from weeks of repeated rain and will be structurally weakened.
- Wait for at least 3–4 consecutive dry days with low humidity and some wind before reassessing; given the sheltered position and runoff issues, longer may be needed.
- If visiting the area, consider non-porous alternatives such as Whinstone crags (e.g. Kyloe-in or Great Wanney) which are far more tolerant of recent rain.
Do Not Climb
72%
3 days ago
Despite two dry days with good wind, the preceding ten days saw repeated rain totalling nearly 44mm over the month, and Corby's Crag's sheltered, below-road-level position with runoff from above means internal moisture is almost certainly still present. The rock may appear surface-dry but the porous, friable Fell Sandstone will not have dried through adequately in just two days given high humidity and moderate temperatures.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's Crag sits below road level and channels runoff from the road and hillside above onto the rock face, meaning it receives more water than open-aspect crags and stays wet longer.
- The rock here is noted as more friable and porous than typical Northumberland sandstone, developing 'scrittle' (loose surface grit) that persists even after the surface looks dry — a sign of incomplete internal drying.
- The sheltered position traps humid air around the crag, significantly slowing evaporation despite any regional wind; the 77% average humidity over the past week compounds this.
- South-facing sections will be in better condition than the NW-facing walls, but even these need more drying time given the cumulative rainfall of the past fortnight.
Warnings
3
- Climbing on this rock while internally damp risks permanent hold breakage on an already friable outcrop — damage to Fell Sandstone routes is irreversible.
- The surface can appear dry while the interior remains saturated; do not rely on visual assessment alone at this crag — check the crag top and base soil moisture as a proxy.
- Incoming rain on June 15–16 will re-wet the rock and reset the drying clock; do not assume today's marginal conditions will improve tomorrow.
Reasoning
With 13.8mm in the last 7 days across multiple rain events (most recently 1.3mm on June 12), and only two full dry days since, the porous Fell Sandstone — especially in this sheltered, runoff-prone setting — is very likely still holding significant internal moisture despite any surface drying.
Two dry days with moderate wind (33–36 km/h on June 13, dropping to 21 km/h today) and temperatures around 13–15°C provide some surface drying, but the sheltered aspect means the crag itself sees far less airflow than open stations suggest, and 70–76% humidity limits evaporative potential.
Given the repeated wetting over the past fortnight and the noted friability of this particular outcrop, there is a meaningful risk of hold breakage and surface grain loosening — the 'scrittle' phenomenon the crag is known for indicates the rock has not recovered structural integrity.
Early June temperatures (10–15°C) and long daylight hours are helpful but not enough to compensate for the prolonged wet spell; this is not the warm, low-humidity weather needed to clear a sheltered sandstone crag after cumulative rain.
Contributing Factors
7
43.7mm over 28 days with 13.8mm in the last week alone across multiple events has kept the porous rock in a near-continuously wetted state.
Two consecutive dry days is well short of the minimum needed for this sheltered, porous crag after repeated heavy wetting — community guidance calls for a long sustained dry period here.
The below-road-level setting traps humid air, channels runoff onto the face, and shields the rock from the drying wind recorded at weather stations.
Winds of 33–36 km/h on June 13 and 21 km/h today would aid surface drying at exposed crags, though the sheltered position reduces this benefit significantly.
Average humidity of 77% over the past week severely limits net evaporation from the rock surface, slowing internal drying.
This crag's rock is noted as more porous and friable than typical Fell Sandstone, meaning it absorbs more water and develops loose 'scrittle' that indicates incomplete drying.
Rain of 1.0mm is forecast for June 15, followed by 6.8mm on June 16, which will reset any drying progress and re-saturate the rock.
Recommendations
3
- Do not climb today — the rock has had only two dry days after a prolonged wet spell and is very likely still damp internally despite any surface drying.
- With rain forecast for June 15–16, the earliest realistic climbing window is June 19–20 if conditions stay dry and windy from June 17 onward — but check the crag top and base for dampness before committing.
- If you visit later in the week, test holds carefully for 'scrittle' (loose surface grit) which indicates the rock has not fully recovered; favour the south-facing sections which dry fastest.
Do Not Climb
72%
4 days ago
Despite today being dry with strong westerly winds, Corby's Crag has received nearly 14mm of rain over the past 7 days across multiple events (most recently 1.3mm yesterday), and only has one consecutive dry day — far too little drying time for this sheltered, below-road-level Fell Sandstone crag that channels runoff from above. The rock is very likely still damp internally, and the 'scrittle' phenomenon noted for this crag means conditions are likely poor even where the surface appears dry.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's Crag sits below road level and channels runoff from the road and hillside above, meaning it receives more moisture than rainfall alone would suggest — it can be wet even when nearby crags are dry.
- The rock here is noted as more friable and porous than typical Northumberland sandstone, and develops 'scrittle' (loose grit on holds) after rain that requires a sustained dry spell with wind to clear.
- The sheltered position significantly reduces air circulation at the rock face despite today's strong winds, meaning effective drying at the crag is much slower than open conditions suggest.
- The south-facing sections will have dried fastest, but the NW-facing sections — which receive minimal direct sun — will retain moisture far longer, especially given recent high humidity averaging 77%.
Warnings
2
- Climbing on this friable, porous sandstone while internally damp risks permanent hold breakage and irreversible route damage — the 'scrittle' effect means holds can fail even when the surface looks dry.
- The rock may appear dry on the surface today but internal saturation from repeated recent rain events makes it structurally weakened — do not be deceived by surface appearance.
Reasoning
With 13.9mm of rain across six separate events in the last seven days, the most recent being 1.3mm just yesterday, the porous Fell Sandstone is almost certainly saturated internally — especially given Corby's additional runoff from above.
Only one dry day with strong wind (37 km/h today) provides some surface drying, but the sheltered below-road-level position limits effective wind at the rock face, and the cumulative soaking from repeated rain events over the past two weeks means internal moisture will persist for several more days.
With the rock likely above 60% pore saturation internally, climbing risks hold breakage on this already-friable sandstone, and the 'scrittle' effect means even apparently dry holds may shed grains under load.
Early June temperatures (averaging ~11°C over the past week) are moderate but not warm enough to drive rapid drying, and the persistently high humidity (77% average) severely limits evaporative potential.
Contributing Factors
7
Six rain events totalling 13.9mm in the past 7 days have kept the rock in a near-continuously wet state, preventing any meaningful internal drying.
A single dry day is far short of the 48–72+ hours needed after cumulative heavy rain on porous sandstone, especially at a sheltered crag.
The crag's position below the road collects additional surface water runoff beyond direct precipitation, amplifying moisture loading.
Despite strong winds recorded at the weather station (37 km/h today), the sheltered below-road setting means effective wind speed at the rock face is substantially reduced.
Average humidity of 77% over the past week limits evaporative drying capacity significantly, keeping moisture locked in the porous stone.
Today's 37 km/h westerly wind will aid surface drying, though its effect is muted by the sheltered crag position.
Temperatures around 13–15°C provide some evaporative energy but are not warm enough to drive rapid drying of deeply saturated sandstone.
Recommendations
3
- Wait for at least 2–3 consecutive fully dry days with moderate wind before visiting; current conditions almost certainly mean the rock is still damp internally.
- If you do visit, check the crag top and base for dampness — if the ground at the base is not sandy-dry, do not climb.
- Consider nearby whinstone or other non-porous alternatives (e.g. Bowden Doors' drier sections or Kyloe) if you need to climb today, but be aware similar weather will have affected the whole region.
Do Not Climb
90%
5 days ago
Corby's Crag has received nearly 15mm of rain over the past 7 days across multiple events, with the most recent rain (5.4mm) only yesterday. Given the crag's sheltered, below-road-level position, high porosity, and runoff channelling from above, the rock will be saturated internally despite today's dry and breezy conditions — climbing would risk both hold breakage and permanent route damage.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's below-road-level position channels surface runoff onto the rock face, meaning cumulative rainfall of 42mm over the past month will have kept the rock repeatedly saturated with little chance to fully dry out between events.
- The condition notes warn of 'scrittle' — loose grit and dust on holds after rain — which indicates the rock is still weakened internally even when the surface appears dry; this is especially likely given the relentless rain pattern from June 1–11.
- The sheltered aspect that makes Corby's warm on sunny days also traps humid air against the rock, and with average humidity at 79% over the past week, evaporative drying has been severely limited.
- South-facing sections will dry faster than the NW-facing walls, but given only one dry day since the last significant rain, even the best-aspect sections are unlikely to be safe.
Warnings
2
- Climbing on saturated Fell Sandstone causes permanent, irreversible damage to holds and routes — the rock may feel dry on the surface while remaining dangerously weak internally.
- The 'scrittle' phenomenon at Corby's means holds can crumble without warning even when the surface appears dry after prolonged wet periods.
Reasoning
With 14.7mm of rain spread across at least five separate events in the last seven days — including 5.4mm just yesterday — the rock is almost certainly saturated well beyond the critical 1% threshold at which significant strength loss begins.
Only one dry day has elapsed since the last rain (5.4mm on June 11), and despite today's strong westerly wind (30 km/h), the sheltered position means effective wind speed at the crag face is much lower, severely limiting drying; the repeated wetting events since June 1 mean the rock has had no opportunity to dry out internally.
The friable, high-porosity Fell Sandstone at Corby's is at serious risk of hold breakage and grain loosening given the prolonged saturation over the past 10+ days — climbing now would cause permanent damage to routes.
Early June temperatures averaging only 11°C over the past week are below seasonal norms for late spring/early summer, further slowing evaporation and drying rates.
Contributing Factors
6
Rain fell on at least 7 of the last 12 days totalling over 26mm since June 1, keeping the rock in a near-continuously saturated state.
Just one day since the last 5.4mm rain event is far short of the minimum 48–72 hours needed for heavy cumulative rainfall on porous sandstone.
The crag's sheltered, sunken position traps humid air and channels road runoff onto the face, dramatically slowing drying compared to exposed crags.
Average humidity of 79% over the past week severely limits evaporative drying, meaning internal moisture has had almost no opportunity to escape.
Today's 30 km/h westerly wind aids surface drying, but the sheltered position means the crag receives only a fraction of this, and one windy day cannot clear deep internal moisture.
Average temperatures of only 11°C over the past week are below seasonal norms and reduce evaporation rates.
Recommendations
3
- Do not climb at Corby's today — the rock is almost certainly saturated internally from repeated rainfall over the past 10+ days and needs an extended dry spell to recover.
- Wait for a minimum of 3–4 consecutive dry, breezy days before visiting; check the crag top and base for dampness before committing to any route.
- Consider visiting a less porous, more exposed venue such as a whinstone or granite crag if you need to climb this week.
Do Not Climb
92%
6 days ago
Corby's Crag is currently unsafe for climbing due to 7.2mm of rain today on top of a prolonged wet spell totalling ~45mm over the past four weeks, with significant rain on most days in the last 10 days. The sheltered, below-road-level position and high porosity of this particular Fell Sandstone mean internal moisture levels will be dangerously high despite any surface drying, and the 'scrittle' phenomenon will likely persist for several days yet.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's below-road-level position channels runoff from above onto the rock face, meaning it receives additional water beyond direct rainfall and will be wetter than nearby crags.
- This crag's sandstone is noted as more friable and porous than typical Northumberland Fell Sandstone, developing 'scrittle' (loose grit) on holds even after surfaces appear dry — a long sustained dry spell is needed to clear this.
- The sheltered setting dramatically slows drying; despite forecast winds of 33–37 km/h, the crag itself will see far less airflow at its below-road position.
- The south-facing sections will dry significantly faster than the NW-facing sections, but given the cumulative saturation from 10+ days of repeated rainfall, even south aspects need extended drying.
Warnings
3
- The rock surface may appear dry well before the interior has dried sufficiently — do not be deceived by surface appearance at this crag.
- Climbing on saturated Fell Sandstone causes permanent, irreversible damage to holds through grain loosening; this crag is noted as particularly susceptible.
- Top-roping causes disproportionate rope-drag erosion on soft Fell Sandstone — avoid entirely until conditions are confirmed dry.
Reasoning
With 18mm in the last 7 days and 45.7mm over 28 days — including rain on 8 of the last 11 days culminating in 7.2mm today — the rock is deeply saturated internally, well above the critical thresholds for strength loss and hold breakage.
Despite the sheltered position receiving less benefit from forecast westerly winds, the upcoming dry spell from June 12 onward with moderate winds (33–37 km/h ambient) and temperatures around 15°C will begin drying, but given cumulative saturation and the crag's known slow-drying character, meaningful internal drying will take at least 3–4 days.
The risk of hold breakage and grain loosening is very high given the prolonged saturation period; the crag's noted friability and 'scrittle' development make climbing particularly damaging and dangerous in current conditions.
Early June temperatures (13–17°C) are helpful for evaporation but not exceptional; the prolonged wet spell is unusual and has prevented the rock from entering the good summer condition window.
Contributing Factors
6
Rain on 8 of the last 11 days totalling ~30mm, plus 7.2mm today, has deeply saturated this porous sandstone well beyond surface level.
The crag's sheltered, sunken position significantly reduces effective wind exposure and traps humid air, dramatically slowing drying compared to exposed crags.
The below-road-level setting means surface water from the road and surrounding land drains onto the rock face, adding moisture beyond direct rainfall.
From June 12 onward, only 0.1mm of precipitation is forecast over 6 days with moderate winds and decreasing humidity, which will begin meaningful drying.
Average humidity of 78% over the past week and 86% today severely limits evaporation rates, keeping the rock saturated for longer.
This crag's unusually porous and friable sandstone develops loose surface grit after wetting, which persists even after the surface appears dry and indicates ongoing internal moisture.
Recommendations
3
- Do not climb at Corby's Crag today or for the next 2–3 days; allow the incoming dry spell to take effect before considering a visit.
- Before any visit later this week, check the crag top and base for dampness — if the ground at the base is not bone-dry, the rock is still unsafe.
- When conditions do improve, start on the south-facing sections which will dry first, and test holds carefully for scrittle before committing to moves.
Do Not Climb
93%
8 days ago
Corby's Crag has received over 20mm of rain in the last 7 days across multiple events, with further rain today and forecast through June 11th — the rock will be thoroughly saturated internally. The sheltered, below-road-level position and high humidity (averaging 79%) mean drying has been negligible between showers, and the notably friable Fell Sandstone here is at serious risk of hold damage.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's Crag sits below road level and channels runoff from above onto the face, meaning it receives significantly more water than open rainfall totals suggest.
- The rock here is described as more friable and porous than typical Northumberland sandstone, developing loose 'scrittle' on holds that persists well after the surface appears dry.
- The sheltered position traps humid air and prevents effective wind-assisted drying despite reasonable wind speeds at weather station level.
- South-facing sections will dry faster than the NW-facing walls, but repeated wetting events over the past 10 days mean even the best-aspect rock is deeply saturated.
Warnings
3
- Climbing on this saturated, friable sandstone risks permanent hold breakage and irreversible route damage.
- The rock surface may appear dry before the interior has dried — do not be deceived by surface appearance at this crag.
- Runoff from the road above can keep the face wet long after rain has stopped; always inspect from the crag top before descending to routes.
Reasoning
Multiple rain events totalling 20.2mm over the last 7 days (and 35.4mm over 28 days), with no consecutive dry days, mean the porous Fell Sandstone is deeply saturated internally despite any brief surface drying between showers.
The sheltered, below-road-level position negates much of the moderate SW winds recorded at station level, and average humidity of 79% severely limits evaporative drying — meaningful drying has not occurred between the repeated rain events since June 1st.
With the rock saturated well above the critical 1% threshold and this crag's particularly friable sandstone, compressive strength is reduced by an estimated 30–50%, creating serious risk of hold breakage and permanent route damage.
Early June temperatures (averaging ~12°C) are moderate but not warm enough to drive rapid drying, especially combined with high humidity and the sheltered aspect; freeze-thaw is not a concern at this time of year.
Contributing Factors
6
Over 20mm across at least five separate rain days in the last nine days has kept the rock in a near-continuously saturated state with no chance to dry out.
Today's forecast shows 2.7mm of scattered showers and tomorrow brings a further 4.3mm, resetting any drying progress.
Average humidity of 79% over the last week severely limits evaporation, especially in the sheltered hollow where Corby's Crag sits.
The below-road-level setting traps moist air and channels additional runoff onto the rock face, making this crag significantly slower to dry than exposed Northumberland venues.
SW winds of 20–28 km/h are recorded but the sheltered crag position means little of this wind reaches the rock face to assist drying.
This crag's unusually porous and friable sandstone absorbs water faster and is more prone to 'scrittle' and hold failure than other Fell Sandstone venues.
Recommendations
3
- Do not climb at Corby's Crag until at least 3 consecutive dry days with low humidity have elapsed after the last rain — realistically no earlier than June 14th at the earliest.
- Before any visit, check the crag top and base for dampness; if the ground at the base is not sandy-dry, the rock is still wet internally.
- Consider alternative non-porous venues (e.g. Whinstone crags like Bowden Doors' whinstone, or the Whin Sill) if you need to climb this week.
Do Not Climb
92%
9 days ago
Corby's Crag has received over 25mm of rain in the past 7 days with the most recent rainfall this morning, and more rain is forecast for the next several days. The rock is almost certainly saturated internally, and the crag's sheltered, below-road-level position means it will take an extended dry spell to recover — one that is not in sight.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's below-road-level position channels runoff from the road and hillside above directly onto the rock face, meaning it receives significantly more water than just direct rainfall.
- The crag is known to develop 'scrittle' — loose grit and dust on holds — after rain, which persists even when the surface looks dry and creates both a safety hazard and damage risk.
- The sheltered position drastically reduces airflow at the rock face despite moderate regional winds, meaning effective drying rates are much lower than the 17–28 km/h regional winds suggest.
- The south-facing sections will dry faster than the NW-facing sections, but the runoff from above and the sheltered setting mean even the south face needs an extended dry window to become safe.
Warnings
3
- Climbing on this saturated Fell Sandstone risks permanent hold breakage and irreversible route damage — the rock is at its weakest right now.
- The 'scrittle' effect at Corby's means even surface-dry rock can be dangerously loose after this much rain; do not trust appearances.
- Runoff from the road above may continue to wet the face for days after rain stops — the rock receives more water than direct precipitation alone.
Reasoning
With 25.4mm in the past 7 days including 4.2mm today and repeated soakings on June 1–4 (totalling ~26mm), the rock is almost certainly saturated well beyond the critical 1% threshold throughout its depth.
Despite moderate regional SW winds, the sheltered below-road-level position limits effective drying; with only brief dry gaps between rain events and humidity averaging 80% over the past week, meaningful drying has not occurred.
The rock is at high risk of hold breakage and grain loosening given likely near-full saturation, with compressive strength reduced by an estimated 30–50% — climbing now would risk permanent damage to this friable Fell Sandstone.
Early June should offer reasonable drying potential, but the current unsettled pattern with repeated frontal rain is preventing the sustained dry spell this crag specifically requires to clear internal moisture and scrittle.
Contributing Factors
6
Over 25mm in the past 7 days across multiple rain events (June 1–4 and June 6–8) has repeatedly re-saturated the rock before any meaningful drying could occur.
4.2mm of rain fell overnight and into the early morning today, ensuring the rock surface and interior are freshly wet.
The crag's sheltered, sunken position below the road dramatically reduces effective wind exposure and channels additional runoff onto the face, greatly extending drying times.
Average humidity of 80% over the past week severely limits evaporation rates, keeping the rock damp even during dry hours.
The next 5 days show further rainfall on June 9 (3.7mm), June 10 (7.3mm), June 11 (0.2mm), and June 12 (2.7mm), preventing any sustained drying window.
Temperatures of 12–14°C are adequate for some evaporation but not high enough to drive rapid drying of deeply saturated porous sandstone in a sheltered setting.
Recommendations
3
- Do not visit Corby's Crag until there have been at least 3–4 consecutive fully dry days with low humidity and some wind — this is unlikely before mid-June at the earliest given the forecast.
- Consider nearby whinstone or limestone alternatives (e.g. Kyloe Crag or Bowden Doors may dry faster due to better exposure) if you need to climb this week.
- When you do eventually visit, check the crag top and base for dampness before committing — if either is moist, the rock interior is certainly still wet.
Do Not Climb
92%
10 days ago
Corby's Crag has received 28.5mm of rain over the past week across multiple events, with the most recent rain today (0.1mm) and significant falls on June 1–4 (26.3mm total). Given the crag's sheltered, below-road-level position, high humidity (83% average), and the site's known tendency to channel runoff from above, the rock will be thoroughly saturated internally and conditions are clearly unsuitable for climbing.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- The below-road-level position channels runoff from the road and surrounding ground onto the rock face, meaning the crag receives far more moisture than rainfall alone would suggest — especially after 28.5mm in a week.
- The site's known 'scrittle' problem (loose grit on holds after rain) will be active given the prolonged wet spell; even once the surface dries, holds will be unreliable until a sustained dry, windy period clears the debris.
- The sheltered aspect that makes Corby's warm on sunny days also traps humid air and dramatically slows drying — the 83% average humidity this week means almost no effective evaporation has occurred.
- The forecast shows rain every day for the next five days (totalling ~21mm), meaning conditions will continue to deteriorate before any drying window opens.
Warnings
2
- The rock surface may appear dry before the interior has dried — climbing on apparently dry but internally saturated Fell Sandstone risks permanent hold breakage on this already-friable crag.
- The 'scrittle' effect (loose grit on holds) will persist well after the surface looks dry; this creates both a safety hazard and causes accelerated erosion of the soft sandstone.
Reasoning
Multiple rain events from June 1–6 totalling 28.5mm, plus runoff channelled from above, will have thoroughly saturated this porous, friable Fell Sandstone well beyond the critical 1% threshold where significant weakening begins.
Only one full dry day (June 5) has occurred since the heavy rain sequence, with today seeing trace precipitation and 80% humidity — in a sheltered position this is grossly insufficient drying time for sandstone that needed 72+ hours of good conditions after heavy rain.
The rock is almost certainly saturated internally, meaning holds are at 10–50% reduced compressive strength; climbing now risks permanent hold breakage on this already-friable crag, compounded by the scrittle effect on loosened surface grains.
Early June temperatures are adequate for drying in principle (12–16°C), but the persistent high humidity and ongoing rain pattern negate any seasonal advantage, and the crag will need an extended dry spell before conditions improve.
Contributing Factors
7
28.5mm over the past seven days across multiple events (June 1–4 and June 6), with the heaviest single day being 8.2mm on June 3, has thoroughly soaked this porous sandstone.
Only one truly dry day (June 5) since the main rain sequence, and today had trace precipitation — far short of the 48–72+ hours needed after heavy rain even at well-drained crags.
The below-road-level, sheltered setting drastically reduces wind-assisted drying and traps humid air, meaning the crag dries much slower than more exposed Northumberland venues.
The road-level position above the crag channels additional surface water onto the face, adding moisture beyond direct rainfall and prolonging saturation.
Average humidity of 83% over the past week severely limits evaporation, leaving the rock's interior saturated even if the surface begins to appear dry.
Wind speeds of 24–28 km/h from SW provide some drying potential, but the sheltered position means the crag itself sees significantly less airflow than open ground.
Rain is forecast every day from June 8–12 (totalling ~21mm), meaning no meaningful drying window will occur for at least five more days.
Recommendations
3
- Do not climb at Corby's Crag until a sustained period of at least 3–4 dry days with low humidity and some wind has occurred — the forecast suggests this won't happen before mid-June at the earliest.
- Consider alternative non-porous rock venues (e.g. Whinstone crags like Crag Lough or Peel Crag on the Whin Sill) if you need to climb this week, as these are far more tolerant of recent rain.
- When conditions do eventually improve, check the crag top and base for dampness before committing — if the ground at the base is moist or the top is seeping, the rock is still dangerously weak internally.
Do Not Climb
92%
11 days ago
Corby's Crag has received nearly 29mm of rain over the past seven days (including 2.4mm today), with high humidity averaging 82% and its sheltered, below-road-level position severely impeding drying. The rock is almost certainly saturated internally, and the forecast offers no meaningful drying window for the next five days, with further rain expected on four of those days.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Corby's below-road-level position channels runoff from the road and surrounding ground onto the rock face, meaning the crag receives more water than open-air rainfall totals suggest.
- The sheltered aspect traps humid air around the crag, and with recent humidity averaging 82–90%, net evaporation from the rock surface will be negligible.
- The crag's notably friable and porous Fell Sandstone develops 'scrittle' — loose grit on holds — after wet periods, which persists well after the surface appears dry and indicates ongoing internal moisture.
- South-facing sections may appear deceptively dry on a sunny afternoon while the NW-facing walls and the base of all routes remain saturated — surface dryness is not a reliable indicator at this crag.
Warnings
3
- Climbing on this saturated, friable sandstone risks permanent destruction of holds and irreversible damage to classic routes.
- Surface-dry appearance is unreliable at Corby's — the rock can look climbable while internally saturated, especially on the south-facing wall on a sunny afternoon.
- The 'scrittle' phenomenon noted at this crag means even apparently dry holds may crumble under load when internal moisture is present.
Reasoning
With 28.7mm in the last seven days including rain today, and a sheltered position that channels additional runoff, the rock is almost certainly saturated well above the critical 1% threshold where significant strength loss begins.
Despite moderate SW winds on some days, the sheltered below-road position nullifies much of the wind benefit, and persistent high humidity (82% average, 90% today) means negligible net evaporation — the rock has had essentially no effective drying time.
The crag's condition notes specifically flag this rock as more friable and porous than typical Northumberland sandstone, meaning the 10–50% compressive strength loss from moisture is likely at the upper end, with high risk of hold breakage and permanent route damage.
Early June should be a reasonable season, but temperatures have dropped to 11–14°C with persistent cloud and rain, reducing drying capacity to well below summer norms; freeze-thaw is not a concern at these temperatures.
Contributing Factors
6
28.7mm over the past week with rain on four of the last six days and 2.4mm today means the rock has been repeatedly re-wetted with no chance to dry.
The crag sits below road level in a sheltered hollow that channels runoff onto the face and traps humid air, dramatically slowing drying compared to exposed crags.
Average humidity of 82% over the past week with 90% today means almost no net evaporation is occurring from the rock surface.
While regional wind speeds are reasonable (15–28 km/h), the sheltered position means little of this wind reaches the rock face to aid drying.
Rain is forecast on four of the next five days (totalling 25.6mm), ensuring the rock will be repeatedly re-wetted with no opportunity to dry.
Temperatures of 11–17°C are below summer averages for the region, reducing evaporative drying capacity.
Recommendations
3
- Do not climb at Corby's Crag until there have been at least 3–4 consecutive dry days with humidity below 70% and moderate wind — given the crag's sheltered position, standard 48-hour guidelines are insufficient.
- If you visit the area, consider nearby whinstone or dolerite venues (e.g. Kyloe or the Whin Sill crags) which are non-porous and dry much faster, though surfaces will still be slippery.
- Monitor forecasts beyond the current 5-day window; the earliest realistic opportunity for safe conditions would be several days after the rain ceases, likely mid-June at the earliest.
Climbing Outlook