Condition Analysis
AI-powered assessment using site data and 14-day weather history
Brimham Rocks is currently too wet to climb safely. Repeated rainfall over recent weeks — including 1.7mm yesterday, 1.2mm today, and significant events on March 24th (20.5mm) and March 29th (10.1mm) — means the gritstone has had no meaningful drying window, and the rock will be saturated internally despite any surface drying.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's diverse formations mean north-facing towers and sheltered alcoves between pinnacles will retain moisture far longer than exposed south-facing faces, creating highly variable conditions across the venue.
- The open moorland setting at 290m means the exposed position aids wind-drying, but the altitude also brings cooler temperatures and more frequent frost cycles — the min of -0.7°C on April 6th and forecast -0.9°C on April 14th indicate ongoing freeze-thaw risk for saturated rock.
- The peat moorland base at Brimham acts as a moisture reservoir; if the ground around the boulders is soft or damp, the rock is certainly still holding internal moisture.
- Many of Brimham's classic problems are on low boulders and landings that sit close to the saturated moorland, meaning moisture wicks upward from the ground as well as soaking in from rain above.
Warnings
2
- Freeze-thaw damage is an active risk with forecast overnight temperatures dropping to -0.9°C on April 14th while the rock remains saturated — climbing on structurally compromised holds could cause permanent route damage and injury.
- Surface-dry gritstone after a brief sunny spell can be deeply misleading; the interior will remain saturated for days given the cumulative rainfall this spring.
Reasoning
The rock has received 8.7mm in the last 7 days alone across multiple events (April 5th: 3.2mm, April 9th: 1.5mm, April 11th: 4.3mm, April 12th: 1.7mm, today: 1.2mm), with no consecutive dry days — the gritstone will be thoroughly saturated internally.
Despite moderate winds (24–50 km/h) and the exposed position, the lack of any consecutive dry period longer than 2 days since March 24th means drying has been repeatedly interrupted, and the cumulative 57.6mm over 28 days has kept the rock in a persistently wet state.
With repeated wetting cycles and overnight temperatures near or below freezing (forecast -0.9°C on April 14th), there is a real risk of freeze-thaw damage to saturated gritstone, and holds could be structurally weakened — climbing now risks permanent damage.
Early spring at 290m altitude means cool average temperatures (~7.3°C over the last week), high humidity (75% average), and limited solar intensity, all of which severely slow the deep drying that porous gritstone requires after a wet March.
Contributing Factors
7
Rain has fallen on 5 of the last 7 days (totalling 8.7mm) with no consecutive dry period, keeping the rock in a continuously wet state.
57.6mm over 28 days with frequent wetting events means the gritstone has had no opportunity to dry internally, even if surfaces occasionally appear dry.
Average humidity of 75% over the past week, with overnight values regularly exceeding 85%, severely limits evaporative drying.
Average temperature of just 7.3°C over the last 7 days provides minimal evaporative energy for drying porous gritstone at depth.
Brimham's exposed moorland position with consistent 20–50 km/h winds aids surface drying, though this cannot compensate for the lack of dry days.
Overnight lows near or below freezing (forecast -0.9°C on April 14th) combined with saturated rock creates active freeze-thaw damage risk.
1.2mm forecast today resets any minor drying progress, ensuring the rock remains saturated heading into the next few days.
Recommendations
3
- Do not climb at Brimham today — the gritstone is saturated from weeks of repeated rainfall and needs a sustained dry period of at least 48–72 hours to begin drying internally.
- Check the moorland ground conditions as a proxy: if the peat and soil around the bases of the formations is damp or soft, the rock is certainly too wet.
- Consider waiting until after April 17th at the earliest, when a potential dry window may begin, and visually inspect rock and ground conditions before climbing.
Previous Analyses
Do Not Climb
85%
2 days ago
Brimham Rocks is currently wet and unsuitable for climbing. Today has received 1.2mm of rain on top of 4.3mm yesterday, and the past two weeks have seen repeated wetting cycles with no sustained dry period — the gritstone will be saturated internally despite any surface drying between showers.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's diverse formations mean north-facing towers and shaded alcoves between pinnacles will retain moisture far longer than the exposed south-facing faces, creating highly variable conditions across the site.
- The open moorland setting provides excellent wind exposure which aids surface drying, but the repeated wetting cycles over the past fortnight mean deeper pore saturation that wind alone cannot resolve quickly.
- Many of Brimham's classic problems are on lower sections of boulders and towers where drainage keeps the rock wettest longest — base-level problems should be avoided well after upper faces appear dry.
- The National Trust manages access at Brimham and climbing ethics here are closely watched; climbing on damp gritstone risks both permanent route damage and potential access restrictions.
Warnings
3
- Climbing on wet or internally damp gritstone causes permanent hold breakage and irreversible route damage — the surface can appear dry while the interior remains dangerously weakened.
- Overnight temperatures near freezing combined with saturated rock create active freeze-thaw conditions that further weaken the stone.
- The past month's 62.6mm of rain with no sustained dry period means even formations that look dry on the surface are likely wet internally — do not trust surface appearance alone.
Reasoning
The rock has been subjected to repeated wetting events over the past two weeks (62.6mm in 28 days) with no period longer than 3 consecutive dry days, meaning the gritstone's internal pore structure is likely near saturation despite brief surface drying between showers.
Today's rain (1.2mm) following yesterday's 4.3mm resets the drying clock; although the exposed position and moderate SW winds help surface evaporation, the persistent humidity (74% average) and cool temperatures (7.2°C average) severely limit effective drying depth.
With repeated saturation cycles and overnight temperatures dropping near or below freezing (min -0.7°C on April 6, 0.9°C on April 10, 1.8°C today), the gritstone faces cumulative freeze-thaw damage risk on top of the 10-50% compressive strength reduction from water absorption.
Early spring conditions in northern England remain challenging — cool temperatures, high background moisture from winter, and frequent frontal systems mean the rock has had very little opportunity to dry out properly since winter.
Contributing Factors
8
Rain has fallen on 9 of the last 14 days with no sustained dry spell longer than 3 days, keeping the porous gritstone in a near-saturated state.
1.2mm today and 4.3mm yesterday completely reset any drying progress from the brief dry spell on April 6-8.
62.6mm over the past 28 days represents substantial total wetting for porous gritstone at this time of year.
The 7.2°C average temperature over the past week provides only modest evaporative drying potential.
Average humidity of 74% limits evaporation rates, though it is not as poor as winter levels.
Strong consistent winds (averaging 30+ km/h recently) significantly aid surface drying between rain events, though they cannot resolve deep saturation.
Overnight minima near or below freezing (0.9°C, 1.8°C) with saturated rock create ongoing freeze-thaw damage potential.
South and west faces benefit from afternoon sun and prevailing wind, but north-facing formations will dry much more slowly.
Recommendations
3
- Do not climb today — the gritstone is wet from today's and yesterday's rain on top of weeks of repeated saturation.
- Monitor conditions through April 14 when a brief drier spell with lower humidity and light frost may begin to improve south-facing surfaces, but verify on-site before climbing.
- If visiting Brimham in the coming days, check the ground at the base of formations — if the peat and soil are damp, the rock interior is almost certainly still wet.
Do Not Climb
90%
3 days ago
Brimham Rocks is actively receiving rain today (4mm) following a very unsettled period, making conditions clearly unsuitable for climbing. The gritstone will be saturated and structurally weakened, with no dry window to allow any meaningful drying.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's open moorland setting means the scattered formations catch rain from all directions, and while the exposed position aids wind-drying, the mixed aspects mean north- and east-facing faces will retain moisture far longer than the south-facing sides.
- The peat and heather moorland surrounding the rocks acts as a moisture reservoir, maintaining high local humidity at the base of formations and slowing drying of lower sections even when upper areas appear dry.
- Many of Brimham's famous balanced boulders and pinnacles have horizontal top surfaces and shelves that pool water, feeding seepage lines down faces for extended periods after rain — watch for dark streaks even days after the last significant rainfall.
- The 290m altitude means overnight temperatures are frequently near or below freezing in early April (min -0.7°C on April 6th, -1.0°C forecast April 14th), creating freeze-thaw risk in any rock still holding internal moisture from recent rain.
Warnings
2
- Climbing on wet gritstone causes permanent, irreversible damage to holds and rock surfaces — please respect the BMC and Yorkshire gritstone ethics by waiting for dry conditions.
- Overnight frost forecast for April 13–14 combined with saturated rock creates freeze-thaw damage risk — the rock may be weaker than usual even once it appears surface-dry.
Reasoning
With 4mm of rain falling today on top of 3.2mm on April 5th, 1.5mm on April 9th, and a very wet March (including 20.5mm on March 24th and 10.1mm on March 29th), the gritstone will be thoroughly saturated with no meaningful drying period.
Despite strong winds today (35.6 km/h), active rainfall negates any drying benefit; the last truly dry spell was only April 6–8 (three days), which was insufficient to fully dry the rock after the preceding wet period.
With the rock near saturation from cumulative recent rainfall, compressive strength will be significantly reduced (potentially 30%+), and climbing risks both hold breakage and accelerated erosion of this irreplaceable gritstone.
Early April at 290m altitude brings overnight frost risk alongside frequent rain, creating dangerous freeze-thaw cycling conditions that compound structural weakening of already-wet gritstone.
Contributing Factors
7
4mm of precipitation is falling today, ensuring the rock surface and interior are actively wet.
There are zero consecutive dry days heading into today, meaning there has been no drying window whatsoever.
61.1mm over the past 28 days with frequent small events means the rock has had no opportunity to fully dry out at depth.
Sustained winds of 35+ km/h on the exposed moorland would significantly aid surface drying once rain stops, but cannot help while rain is active.
Temperatures around 8°C are adequate for some evaporation but not fast drying, especially combined with current humidity.
Average humidity of 73% over the past week, with spikes to 85%+ on rain days, slows evaporative drying between showers.
Overnight minima near or below 0°C forecast for April 13–14 could cause freeze-thaw damage in rock that remains saturated from current rainfall.
Recommendations
3
- Do not climb at Brimham today — the rock is actively wet and structurally compromised.
- Monitor conditions from April 14 onwards; if the forecast holds with minimal rain on April 13–14 and dry weather from April 16, south-facing formations may begin to come into condition by mid-to-late next week.
- When you do visit, test conditions by checking the base of formations — if the ground and lower rock are damp to the touch, the interior is still too wet to climb safely.
Do Not Climb
40%
4 days ago
Despite today being dry with good wind and lower humidity, the rock received 1.5mm of rain yesterday (April 9th) and has had only one full dry day. The preceding weeks have been persistently wet with 63mm over 28 days, meaning the gritstone is likely still holding significant internal moisture despite possible surface drying.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's scattered formations mean north-facing towers and sheltered alcoves between pinnacles will retain moisture much longer than the exposed south-facing faces, so conditions will vary dramatically across the site.
- The open moorland setting and today's strong SW wind (37 km/h) will accelerate surface drying on exposed faces, but the many recessed cracks, offwidths, and sheltered bases between boulders will remain damp far longer.
- The cumulative 63mm over 28 days — including a heavy 20.5mm event on March 24th and 10.1mm on March 29th — means the gritstone's pore network has been repeatedly recharged with little opportunity to fully dry out.
- Several nights have dipped near or below freezing recently (April 6th: -0.7°C, today's min: 1.4°C), and with the rock still holding internal moisture, freeze-thaw micro-damage is an ongoing concern at 290m altitude.
Warnings
2
- The gritstone is almost certainly still wet internally despite any surface drying — climbing risks permanent hold breakage and route damage at this irreplaceable National Trust site.
- Overnight temperatures near freezing combined with residual internal moisture create active freeze-thaw conditions that further weaken the rock.
Reasoning
With 1.5mm of rain yesterday, only one dry day since, and a persistently wet month (63mm in 28 days with no extended dry spells), the gritstone is very likely still holding significant internal moisture despite surface conditions potentially appearing dry on exposed south-facing faces.
Today's strong SW wind (37 km/h) and lower humidity (67%) are helpful for surface evaporation, but a single dry day is far short of the 48–72+ hours minimum needed after the cumulative recent rainfall, and the preceding weeks offered no extended drying window.
The repeated wetting cycles over the past month without adequate drying periods mean the gritstone's compressive strength is likely significantly reduced; climbing risks hold breakage and accelerated erosion on this heavily-trafficked National Trust site.
Early April at 290m altitude brings marginal temperatures (min 1.4°C today) and the tail end of freeze-thaw risk season, compounding the structural concerns from persistent internal moisture.
Contributing Factors
7
1.5mm fell on April 9th, leaving only one full dry day — well below the minimum 48-hour drying requirement for gritstone.
63mm over 28 days with no extended dry spell means the rock's pore network has been repeatedly recharged, keeping internal saturation elevated.
37 km/h SW winds on exposed moorland will significantly accelerate surface evaporation on windward faces.
67% relative humidity is the lowest in over a week, improving net evaporation potential.
South and west-facing formations will dry fastest, but north-facing towers and sheltered recesses will remain damp much longer, creating highly variable conditions.
Average temperature of only 7°C over the past week with overnight lows near freezing slows drying and raises freeze-thaw concerns while internal moisture remains.
Looking back over the past month, there has been no period of 3+ consecutive fully dry days with good drying conditions — the rock has never had a proper chance to dry out.
Recommendations
3
- Wait for at least 48 hours of dry weather with good wind before climbing; current conditions do not meet safe drying thresholds for gritstone.
- If visiting the site, use the base-of-crag ground moisture test — if the soil and rock bases are still damp, the gritstone interior is certainly wet.
- Check the BMC RAD for any bird nesting restrictions at Brimham, as peregrine and raven nesting season (February–June) may restrict access to some formations.
Marginal — Assess Conditions
55%
5 days ago
After three full dry days (April 6–8) with notably warm temperatures peaking at 19.2°C yesterday and moderate wind, south and west-facing formations at Brimham are likely approaching climbable condition, but the heavy 28-day rainfall total (76.5mm) and persistent high humidity mean internal moisture may linger — especially on north-facing surfaces and lower sections. Today's 0.3mm trace rain and 81% humidity add further uncertainty, so on-site assessment is essential.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's scattered tower and pinnacle formations mean every face has a different aspect and wind exposure — south-facing open towers will be significantly drier than sheltered north-facing alcoves or enclosed corridors between formations.
- The moorland setting means the peat and heather ground can remain boggy for days after rain; if the ground at the base of a formation is still damp, the rock is almost certainly still wet internally.
- Many Brimham problems start from low-level landings that collect drainage from the formations above — these base sections are the last to dry and most vulnerable to damage.
- The 20.5mm deluge on March 24 followed by repeated light showers through early April means the rock has been repeatedly re-wetted and has not had a sustained drying window until the last three days.
Warnings
2
- The 76.5mm of rain in the last 28 days means deep internal moisture is likely present despite surface drying — gritstone can appear dry while remaining structurally weakened.
- Do not climb on any surface that feels cool to the touch or shows darker patches, as even slight internal dampness causes significant strength loss in gritstone.
Reasoning
Three consecutive dry days (April 6–8) with excellent warmth yesterday (19.2°C) have provided reasonable surface drying, but the 76.5mm cumulative rainfall over 28 days — including 20.5mm on March 24 and repeated light showers through April 5 — means deep internal moisture is likely still present, particularly in thicker formations and north-facing rock.
The warm spell of April 6–8 (up to 19.2°C, humidity dropping to 55%) with the exposed moorland position provided good drying conditions on south and west aspects, but today's return to 12.8°C, 81% humidity, and 0.3mm precipitation interrupts that drying trend and may re-wet surfaces slightly.
Given the prolonged wet March and repeated wetting cycles, gritstone grain cohesion will still be compromised in any sections retaining internal moisture — climbing on apparently dry but internally damp rock risks hold breakage and permanent damage.
Early April at 290m brings cool overnight temperatures (down to -0.7°C on April 6) creating potential frost damage risk on saturated rock, and the spring transition means drying capacity is limited compared to summer conditions.
Contributing Factors
7
April 6–8 were completely dry with warm temperatures peaking at 19.2°C, providing the best drying window in weeks.
76.5mm over the past 28 days with repeated re-wetting events means the rock has had little opportunity to dry deeply before the recent dry spell.
0.3mm forecast today with 81% humidity interrupts the drying trend and may re-wet surface rock slightly, resetting the clock on the most recent dry window.
Brimham's exposed position with consistent 20–30 km/h winds throughout the dry spell significantly accelerates surface evaporation on wind-exposed faces.
Average humidity of 77% over the last 7 days and overnight readings regularly above 85% limit evaporative drying capacity, particularly overnight.
South and west-facing towers will have benefited most from yesterday's sun and warmth, while north-facing surfaces and sheltered gullies will be significantly damper.
Minimum of -0.7°C on April 6 and near-zero nights mean any internally saturated rock faces freeze-thaw damage risk, compounding structural weakness.
Recommendations
3
- Prioritise south and west-facing exposed towers and pinnacles that have had maximum sun and wind exposure; avoid north-facing problems and sheltered alcoves entirely.
- Check the ground at the base of each formation before climbing — if the peat or soil is damp, the rock above is almost certainly still wet internally.
- If you do climb, stick to well-drained overhanging or steep features and avoid slabs and cracks where moisture lingers longest; be prepared to walk away if any hold feels gritty or soft.
Marginal — Assess Conditions
62%
6 days ago
After 3.2mm of rain on April 5th, Brimham has had two full dry days (April 6–7) with excellent drying conditions yesterday — warm temperatures up to 15.6°C, low humidity (45–48% in the afternoon), clear skies, and moderate wind. However, the preceding weeks have been persistently wet (78mm in 28 days), and today's trace precipitation (0.1mm) plus elevated humidity (78%) introduce some uncertainty, particularly for north-facing formations and lower sections of the rocks.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's scattered tower and pinnacle formations mean every aspect is represented — south-facing surfaces will have dried significantly faster than north-facing ones over the last two days, so climbers should be selective about which formations they approach.
- The exposed moorland position has provided good wind-assisted drying, but the base of many formations sits on peat and heather which retains moisture and can wick dampness into lower rock sections.
- Some of the deeper crack systems and chimneys (e.g. Minion's Way area, Cubic Block chimney routes) are sheltered from wind and sun, and will retain moisture far longer than exposed faces.
- The National Trust site has open access but ground conditions on the moorland paths may be boggy after the wet March — if the ground around the base of formations is damp, treat this as a strong indicator the rock is not fully dry internally.
Warnings
2
- Do not assume all formations are equally dry — north-facing pinnacles and sheltered chimneys may still be significantly damp despite two dry days.
- The prolonged wet winter/spring (78mm in 28 days) means internal rock moisture may be higher than surface conditions suggest — holds could be structurally weakened even where the surface appears dry.
Reasoning
The last significant rain was 3.2mm on April 5th, preceded by a very wet period (78mm in 28 days including 20.5mm on March 24th and 10.1mm on March 29th), meaning the rock likely had a high baseline moisture content going into the current drying window.
Two full dry days (April 6–7) with yesterday providing exceptional drying — 15.6°C peak, humidity dropping to 45%, moderate SE wind, and full sun — have likely dried exposed south and west-facing surfaces adequately, but north-facing formations and sheltered areas at this altitude will have dried more slowly.
The prolonged wet winter and spring mean cumulative moisture loading has been high, and while freeze-thaw risk is now low (min temps just above 0°C), internal moisture from weeks of saturation may still compromise grain cohesion in less-exposed sections.
Early spring at 290m altitude means temperatures are only just becoming consistently helpful for drying, and the high average humidity of 76% over the past week has limited evaporative potential despite the exposed position.
Contributing Factors
8
3.2mm fell on April 5th after a very wet month (78mm in 28 days), meaning baseline rock moisture was elevated before the current short drying window.
April 6–7 were fully dry with April 7th providing outstanding drying conditions: 15.6°C, 45% humidity, clear skies, and moderate wind.
Brimham's high, exposed position means wind-assisted drying has been effective across the open formations, particularly on windward faces.
The scattered pinnacles and towers present every aspect, meaning north-facing and sheltered surfaces will have dried far less than sun-exposed ones.
Average humidity of 76% over the past week and 78% today limits evaporative drying, especially overnight and in sheltered spots.
The cumulative 78mm over 28 days means deep rock moisture is likely still elevated even where surfaces appear dry.
The 0.1mm forecast for today is negligible and unlikely to meaningfully re-wet surfaces, but indicates non-ideal atmospheric conditions.
Today's forecast high of 18.5°C is the warmest this spring and will significantly aid surface drying through the day.
Recommendations
3
- Focus on south and west-facing formations that have had maximum sun and wind exposure over the last two days; avoid north-facing surfaces and deep crack/chimney routes.
- Apply the ground-moisture test: if the peat and soil at the base of a formation is damp, do not climb on that formation — it indicates the rock is not fully dry internally.
- Given the wet spring, use only soft boar's hair brushes and be especially gentle with holds, as prolonged moisture may have weakened grain bonding even where surfaces feel dry.
Marginal — Assess Conditions
55%
8 days ago
The last meaningful rain was 3.2mm on April 5th (yesterday), following a very wet March with 78.5mm over 28 days. Today is dry with moderate wind and lower humidity (73%), but only one full dry day has elapsed since the last rain, and the rock has been repeatedly saturated through the preceding weeks — south- and west-facing exposed formations may be approaching climbable condition, but north-facing and sheltered features will still hold moisture.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's scattered formations face all directions, so while south-facing towers may feel dry, north-facing sides of the same formation can remain damp for days longer — always check the specific aspect of your chosen problem.
- The exposed moorland position and strong winds over recent days (45–50 km/h on April 3–5) have significantly aided surface drying, but the deeply weathered gritstone and honeycomb features trap moisture internally.
- The ground around many boulders sits on peaty moorland that retains water; if the peat/grass at the base of a formation is still moist, the rock is very likely still damp internally.
- March was exceptionally wet (78.5mm in 28 days) with repeated wetting cycles, meaning the rock has had little chance to fully dry out at depth — even surface-dry rock may be weakened internally.
Warnings
2
- The rock has been repeatedly saturated over the past month — surface-dry appearance is NOT a reliable indicator of internal condition; apply the touch test and ground moisture check before climbing.
- Overnight frost (-0.7°C) following yesterday's rain may have caused freeze-thaw stress on near-surface rock; be especially cautious with small holds and flakes.
Reasoning
The rock received 3.2mm yesterday across scattered showers, on top of a very wet preceding month (78.5mm in 28 days) with rain on most days in late March and early April, meaning deep saturation is likely despite surface drying.
Only one dry day has elapsed since the last rain, but strong westerly winds (49.7 km/h yesterday) and today's lower humidity (73%) with moderate southerly wind and warmer temperatures (12°C) are providing reasonable drying conditions — exposed south-facing formations will be furthest along, but the community standard of two dry days has not yet been met.
With repeated wetting over the past month and only one day of drying, internal moisture levels in the gritstone are likely still elevated, posing a real risk of grain loosening and hold breakage, particularly on less-trafficked features.
Early April at 290m means overnight frost is still possible (min -0.7°C today), and the overnight freeze following yesterday's rain could have caused minor freeze-thaw stress on saturated rock near the surface.
Contributing Factors
7
3.2mm fell across scattered showers on April 5th, with the last precipitation at 18:00, giving less than 24 hours of drying time.
78.5mm over 28 days with frequent wetting events means deep rock saturation that cannot be resolved in one or two dry days.
Brimham's exposed moorland position combined with strong winds over recent days (45–50 km/h) significantly accelerates surface evaporation on windward faces.
Today is forecast dry with 12°C maximum, 73% humidity, and moderate southerly wind — good drying conditions that will help surface layers.
With formations facing all compass points, north- and east-facing sides will dry much more slowly than south- and west-facing surfaces.
Minimum of -0.7°C overnight following yesterday's rain means the rock surface may have undergone a freeze-thaw cycle while still partially saturated.
Average humidity over the last 7 days was 79%, and today's 73% is acceptable but not low enough to drive rapid deep drying.
Recommendations
3
- Wait until late afternoon today or ideally tomorrow (April 7th, forecast 16°C, dry, and breezy) for the best chance of adequately dried rock, focusing on south- and west-facing exposed formations only.
- Check the peat and grass at the base of your chosen formation — if the ground is damp, do not climb, as the rock above is almost certainly still holding internal moisture.
- Avoid north-facing features and any routes with known seepage lines or sheltered alcoves for at least another 2–3 days given the wet preceding month.
Do Not Climb
35%
9 days ago
Brimham Rocks has had a persistently wet March with 77.5mm over the last 28 days, and today sees another 2.2mm of rain — there have been zero consecutive dry days. Despite strong winds aiding surface drying, the cumulative moisture loading on this porous gritstone means internal saturation is very likely, and climbing today would risk both hold damage and climber safety.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's exposed moorland position at 290m means the strong westerly winds today (50 km/h) will strip surface moisture quickly, but this can create a dangerously deceptive 'surface-dry, internally-wet' state on the gritstone.
- The all-aspect nature of the formations means north- and east-facing surfaces will have dried far more slowly than south/west faces throughout this prolonged wet period — condition variability across the site will be extreme.
- The moorland setting with peaty ground retains moisture at crag bases; if the ground around the formations is boggy or damp, the rock is almost certainly still holding significant internal moisture.
- Some of Brimham's lower boulders and sheltered formations tucked between larger blocks receive less wind and can hold seepage and dampness for days longer than the exposed pinnacles and upper faces.
Warnings
3
- Freeze-thaw damage risk is elevated tonight and tomorrow morning with sub-zero temperatures forecast on saturated rock — climbing on frost-affected gritstone can cause irreversible hold breakage.
- Surface rock may appear dry in the wind while remaining internally saturated — do not be deceived by surface appearance at Brimham after this prolonged wet period.
- The cumulative winter/spring moisture loading means even apparently dry-looking gritstone may still be significantly weakened internally.
Reasoning
With 77.5mm of rain over the past 28 days, frequent light rain events through late March and early April (including 10.1mm on March 29, 20.5mm on March 24, and 14.7mm on March 12), plus 2.2mm today, the gritstone has had almost no opportunity to dry out internally and is very likely at or near critical saturation levels.
Although today's 50 km/h westerly wind and relatively low humidity (70%) will promote rapid surface evaporation, the rock has not had a single fully dry day and the longest dry spell in recent weeks was only 6 days (March 17–22), which was then undone by 20.5mm on March 24; deep internal drying has been impossible.
With prolonged saturation through late winter and early spring, compressive strength of the gritstone is likely reduced by 10–50%, and the overnight minimum of 0.3°C today combined with sub-zero temperatures forecast tomorrow morning (-2.7°C) creates a real freeze-thaw risk on saturated rock.
Early April at 290m altitude is still firmly within the vulnerable spring transition period where cumulative winter moisture loading has not yet dissipated, and overnight frost risk persists — conditions typically do not become reliably climbable at Brimham until sustained dry spells arrive later in spring.
Contributing Factors
6
77.5mm over 28 days with almost no extended dry windows means deep internal moisture saturation of the porous gritstone is virtually certain.
Even light rain today resets the drying clock and means zero consecutive dry days heading into the forecast period.
Today's 50 km/h westerly and Brimham's exposed moorland position significantly accelerate surface evaporation, though this cannot address deep internal moisture.
Tonight's minimum near 0.3°C and tomorrow's forecast minimum of -2.7°C create a dangerous freeze-thaw cycle on rock that is likely above the 60% critical saturation threshold.
Humidity at 70% today and averaging 79% over the past week is neither particularly helpful nor harmful — it allows some evaporation but is far from the ideal low-humidity conditions needed for rapid drying.
Average temperature of just 6.6°C over the past week limits evaporative drying potential, and at 290m altitude conditions remain cool enough to significantly slow the drying process.
Recommendations
3
- Wait for the promising dry spell forecast from April 6–8 to allow at least 48–72 hours of drying before attempting any climbing, with south- and west-facing exposed pinnacles likely to be the first to come into condition.
- Check the ground conditions around the base of the formations on arrival — if the moorland turf and peat are still saturated, the rock will be too.
- If visiting later in the week, prioritise the higher, more exposed and south-facing formations first, and avoid lower sheltered boulders and north-facing walls which will take longest to dry.
Do Not Climb
90%
10 days ago
Brimham Rocks is currently wet and unsuitable for climbing. Heavy rain on March 29th (10.1mm) was followed by repeated light rain events through to today (2.9mm falling today), with no consecutive dry days accumulated; the gritstone will be saturated internally despite the strong winds.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's mixed aspects mean north- and east-facing formations will be significantly wetter than south-facing towers, and seepage from the moorland plateau above can feed moisture into cracks and horizontal breaks for days after rain.
- The exposed moorland position delivers excellent wind drying, but with rain falling today and on most recent days, even the windiest formations have not had a chance to begin meaningful drying.
- The porous gritstone towers and balanced boulders have complex 3D drainage — water percolates down through horizontal bedding planes and re-emerges lower on formations, keeping base sections and underclings wet long after the tops appear dry.
- National Trust access at Brimham is permissive and high-profile; climbing on visibly wet rock here risks reputational damage to the climbing community and potential access restrictions.
Warnings
3
- Freeze-thaw damage risk is high over the next two nights as saturated rock encounters sub-zero temperatures — climbing on recently frozen gritstone is extremely dangerous.
- The rock surface may appear dry on wind-exposed faces while remaining saturated internally; do not trust surface appearance alone after this prolonged wet period.
- Hold breakage risk is elevated across the entire venue due to deep saturation from nearly 77mm of rain in the last month.
Reasoning
With 2.9mm of rain today, 1.1mm yesterday, 0.9mm the day before, and 10.1mm on March 29th — plus 76.9mm over the last 28 days — the gritstone is almost certainly saturated internally, well above the critical ~1% moisture threshold where significant strength loss begins.
Despite strong SW winds (52.9 km/h today), zero consecutive dry days means no meaningful drying has occurred; the repeated wetting cycle over recent weeks has kept the rock in a persistently moist state with no opportunity for the 48–72+ hours of dry weather needed after heavy rain.
At current saturation levels, compressive strength is likely reduced by 10–50%, with high risk of grain loosening and hold breakage — particularly on the finer-textured faces and edges that characterise many Brimham problems.
Early April at 290m altitude with overnight temperatures dropping below freezing (forecast -0.4°C and -2.9°C in coming nights) creates active freeze-thaw risk on saturated rock, compounding structural vulnerability.
Contributing Factors
7
2.9mm of precipitation today means the rock surface is actively wet, with no drying period yet begun.
The last 7 days have seen rain on nearly every day (15.8mm total), preventing any meaningful drying cycle from starting.
76.9mm over 28 days indicates a prolonged wet period that will have deeply saturated the porous gritstone.
Sustained SW/W winds of 25–53 km/h will significantly accelerate surface drying once rain stops, but cannot overcome active wetting.
Overnight lows of -0.4°C and -2.9°C forecast over the next two nights on saturated rock creates damaging freeze-thaw conditions.
81% average humidity over the past week slows evaporative drying even in windy conditions.
Daytime temperatures of 8–13°C provide some drying potential but are insufficient to overcome ongoing moisture input.
Recommendations
3
- Do not climb at Brimham today — the rock is actively wet and structurally compromised.
- Monitor conditions from April 7th onwards when a dry spell with warming temperatures and lower humidity is forecast, though verify dryness on arrival.
- If visiting the area, consider non-porous alternatives such as limestone crags that are not affected by the same structural concerns when damp.
Do Not Climb
70%
11 days ago
Brimham Rocks has received nearly 80mm of rain over the past 28 days with repeated wetting events, including 10.1mm on March 29 and 20.5mm on March 24, and today itself has seen 1.7mm of rain. Despite some strong drying winds, the rock has had zero consecutive dry days and the gritstone is very likely still holding internal moisture, particularly on north-facing formations.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Brimham's scattered tower and pinnacle formations mean every aspect is represented — north-facing sides of blocks will be significantly damper than south-facing sides, and climbers should not assume conditions on one formation apply to another.
- The open moorland setting provides excellent wind exposure which aids surface drying, but the peat and heather ground around many formations retains moisture and can indicate internal rock dampness — check the base of boulders for damp ground.
- Many of Brimham's classic problems are on lower sections and undercuts of formations where water drains to and pools; these areas will be the last to dry after this prolonged wet spell.
- As a National Trust site, Brimham sees heavy foot traffic and social climbing; the ethical responsibility to avoid wet gritstone is especially important here given the high volume of use these formations receive.
Warnings
2
- Climbing on wet gritstone causes permanent, irreversible damage to holds and route surfaces — Brimham's unique formations are irreplaceable.
- Freeze-thaw cycles are still possible at 290m with overnight lows near 0°C; saturated rock is at risk of structural damage even without climbing.
Reasoning
With 79mm of rain in 28 days, repeated wetting events (most recently 1.7mm today, plus light rain on several of the last few days), and average humidity of 81%, the gritstone at Brimham is almost certainly carrying significant internal moisture despite some surface drying between showers.
The strong westerly and south-westerly winds (often 25-50 km/h) on this exposed moorland have aided surface evaporation, but the lack of any sustained dry period — zero consecutive dry days as of today — means the rock has been repeatedly re-wetted before it could dry internally.
Millstone Grit that has been repeatedly soaked over weeks with no extended drying window is at elevated risk of grain loosening and hold breakage; the 80% strength loss occurring within hours of wetting means each re-wetting event resets the damage risk.
Early April at 290m altitude means overnight temperatures are still dropping near or below freezing (min 0.3°C forecast tomorrow), creating freeze-thaw risk in saturated rock, and the low sun angle limits solar drying on north-facing formations.
Contributing Factors
6
79mm in 28 days with 15.8mm in the last 7 days and 1.7mm today means the rock has been repeatedly saturated with no opportunity to fully dry.
Today has recorded 1.7mm of precipitation, meaning there has been no unbroken dry spell for proper internal drying since the last significant rain.
Sustained winds of 25-50 km/h on exposed moorland significantly accelerate surface evaporation and would aid drying if a dry window materialises.
Average humidity of 81% over the past week substantially limits the rate of evaporative drying from the rock surface.
Minimum temperatures near or below 0°C (forecast 0.3°C tomorrow) combined with saturated rock create active freeze-thaw damage risk at 290m altitude.
South and west-facing formations will be in the best condition, but north-facing sides — which host many classic problems — will retain moisture far longer.
Recommendations
3
- Wait for at least 48-72 hours of genuinely dry weather with humidity below 75% before visiting; the forecast suggests April 6-7 may offer the first realistic window.
- If you do visit, check for damp ground at the base of formations as a reliable indicator of internal moisture — if the peat is wet, the rock is wet.
- Focus on south and west-facing overhanging formations only if conditions improve, and avoid any routes on north-facing aspects or lower sections of boulders for several days yet.
Climbing Outlook