Condition Analysis
AI-powered assessment using site data and 14-day weather history
Great Wanney has received repeated rainfall over the past week with no meaningful dry spell, and today itself has 1.5mm forecast. The Fell Sandstone will be saturated internally despite any surface drying, and the ongoing pattern of frequent precipitation means there has been no adequate drying window.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's dramatic 10–20m escarpment means the lower sections will hold moisture longest as water drains down through the porous sandstone from above, and the base areas where many routes start will be slowest to dry.
- The 20–30 minute walk-in crosses boggy moorland — if the approach ground is waterlogged, this is a reliable indicator that the crag itself has not dried out internally.
- The exposed S/SW aspect and moorland setting normally aid drying significantly, but the persistent high humidity (averaging 76% over the last week) and cool temperatures have severely limited evaporative potential.
- Many of the lower-grade routes (VDiff–Severe) at Great Wanney are noted as serious for their grade, meaning holds are already marginal when dry — any moisture-related weakening of the sandstone makes these routes genuinely dangerous.
Warnings
3
- Active freeze-thaw risk: overnight frost forecast tonight (-1.2°C) on saturated sandstone can cause hidden structural damage and sudden hold failure.
- The rock surface may appear deceptively dry during windy afternoon periods while remaining dangerously saturated internally — do not be fooled by surface appearance.
- Repeated wet climbing on Fell Sandstone causes cumulative, irreversible erosion and hold loss; the NMC ethic of 'Love the rocks' means waiting is the only responsible choice.
Reasoning
The rock is almost certainly saturated internally: 3.6mm fell on April 12, 1.5mm is falling today (April 13), and prior to that there were rain events on April 9 (1.9mm), April 11 (3.5mm), and April 5 (2.0mm) with no consecutive dry period longer than 2 days in the past fortnight.
Despite the exposed S/SW aspect and moderate winds (averaging ~25 km/h), the persistent humidity around 76–88% and cool temperatures (average ~6.5°C) have severely curtailed drying; there has been zero consecutive dry days as of today, making meaningful drying impossible.
With repeated wetting events and overnight temperatures dropping below 0°C on several recent nights (April 2, 5, 6, 10, and forecast tonight at -1.2°C), there is active freeze-thaw risk on rock that is likely above the 60% critical saturation threshold, creating serious hold breakage danger.
Early spring in Northumberland at 280m altitude means limited solar intensity, cool temperatures, and frequent frost cycles — this is the most vulnerable period for Fell Sandstone and conditions have been consistently poor throughout March and into April.
Contributing Factors
7
Rain has fallen on 6 of the last 7 days (10.5mm total in the last week) with no consecutive dry period, keeping the sandstone in a perpetually saturated state.
Zero consecutive dry days as of today, and the last meaningful dry spell was April 6–8 (3 days) which followed 2mm of rain on April 5 — wholly insufficient for deep drying.
Average temperature over the last 7 days is only 6.5°C, which severely limits evaporative drying of porous sandstone.
Humidity has averaged 76% over the past week with spikes to 88–91%, significantly reducing the moisture gradient needed for effective rock drying.
Multiple overnight frosts recently (including forecast -1.2°C tonight) combined with likely high internal saturation creates active freeze-thaw damage risk above the 60% critical threshold.
The S/SW aspect and exposed moorland setting provide above-average wind exposure and solar radiation, which would aid drying if a sustained dry spell occurred.
41.9mm of precipitation over the past 28 days with frequent wetting events means the rock has had no opportunity to dry deeply, and internal moisture levels will be very high.
Recommendations
3
- Do not climb at Great Wanney today — the rock is almost certainly saturated internally and climbing risks permanent damage to holds and routes.
- Wait for at least 48–72 hours of continuous dry weather with wind and temperatures above 8°C before considering a visit; check that the approach moorland is dry underfoot as a proxy for crag condition.
- If visiting the area, consider alternative non-porous rock venues (e.g. whinstone crags) where structural damage from moisture is not a concern, though friction may still be reduced.
Previous Analyses
Do Not Climb
70%
2 days ago
Despite a promising dry spell from April 6–8, recent rain on April 9 (1.9mm), April 11 (3.5mm), and today April 12 (0.9mm) has re-wetted the rock with zero consecutive dry days. The cumulative 41.8mm over the past 28 days and ongoing intermittent showers mean the sandstone has had no adequate drying window, and climbing today risks both hold damage and personal safety.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's 10–20m escarpment means the lower sections will retain moisture longest as water drains down from the upper face — the base routes (many of which are the serious VDiffs and Severes) will be the last to dry.
- The 20–30 minute boggy walk-in is itself a moisture indicator: if the moorland approach is waterlogged, the crag is almost certainly still holding internal moisture.
- The south/south-west aspect and exposed moorland position are significant positives for drying — given a genuine 48-hour dry window with wind, this crag dries faster than most Northumberland sandstone venues.
- The crag sits at 280m where overnight frosts are still occurring (multiple sub-zero minimums in recent weeks), creating ongoing freeze-thaw risk in any rock retaining internal moisture from the recent wet period.
Warnings
3
- Fell Sandstone loses up to 50% of its compressive strength when wet — climbing today risks permanent hold breakage and irreversible route damage.
- Overnight frosts combined with internal rock moisture create active freeze-thaw conditions that further weaken the sandstone structure.
- The surface may appear dry in wind and sun while the interior remains saturated — do not be deceived by surface appearance alone.
Reasoning
Rain fell on April 9 (1.9mm), April 11 (3.5mm), and today April 12 (0.9mm), with no consecutive dry days — the rock is almost certainly wet internally despite any surface drying between showers.
The SW-facing exposed aspect and moderate winds (23–30 km/h) would normally aid drying, but the repeated re-wetting every 1–2 days has prevented any meaningful drying progression since April 9.
With 41.8mm of rain in the past 28 days and repeated wetting cycles, the sandstone's internal moisture is likely well above the threshold where significant strength loss occurs, and overnight frosts near or below 0°C add freeze-thaw risk.
Early April in Northumberland at 280m remains marginal for sandstone climbing — temperatures are cool (averaging 6.3°C over the last week), frosts are still occurring, and the prolonged wet late winter/early spring means deep moisture may persist in the rock matrix.
Contributing Factors
7
Rain on April 9, 11, and 12 (totalling 6.3mm in the last 7 days) with zero consecutive dry days means the rock has been repeatedly re-wetted with no drying window.
41.8mm over 28 days with frequent small rainfall events has kept the porous sandstone chronically damp through the period.
Average temperature of 6.3°C over the past week provides only slow evaporative drying, well below the levels needed for rapid moisture removal.
Multiple recent overnight minima near or below 0°C (including -2.8°C, -2.9°C, and -1.1°C in recent weeks) combined with internal moisture creates cumulative freeze-thaw damage risk.
The south/south-west facing, exposed moorland setting means the crag receives good solar radiation and wind, which would accelerate drying if given a sustained dry period.
Today's 30 km/h SW wind helps surface evaporation, but with rain also falling today, the net effect is limited.
Humidity averaging 76% over the past week limits the vapour pressure gradient needed for effective drying of the rock interior.
Recommendations
3
- Do not climb today — wait for at least 48 hours of completely dry weather with wind before considering a visit.
- Monitor the forecast closely: if April 14 stays dry after the April 13 shower, April 15's heavy rain (10.8mm) will reset any drying progress, so realistically the next viable window may not arrive until late April.
- On arrival, check the moorland approach path — if it is boggy and waterlogged, treat this as confirmation that the rock is too wet internally regardless of how the surface looks.
Do Not Climb
90%
3 days ago
Great Wanney is receiving rain today (4.8mm) and has had a persistently unsettled period with no meaningful dry spell; the Fell Sandstone will be wet internally and must not be climbed. The forecast offers no adequate drying window in the next five days, with further rain expected tomorrow and a heavy event (18.6mm) on April 15th.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's exposed moorland setting at 280m means strong winds aid surface drying, but the high altitude also brings cooler temperatures and more frequent precipitation than lower crags, limiting net drying benefit.
- The S/SW aspect is favourable for solar drying in spring, but April sun angles at this latitude provide only moderate radiation and the recent pattern of frequent light rain events has prevented the rock from ever fully drying out.
- The boggy walk-in approach is a useful proxy indicator — if the moorland is waterlogged (highly likely given recent rainfall totals), the crag base will also be retaining moisture and the rock will be wet internally.
- The 12.9mm event on March 24th and subsequent lack of any sustained dry period (no run of 3+ consecutive dry days since) means the sandstone has likely been in a semi-saturated state for weeks, compounding the moisture problem beyond what today's rain alone would suggest.
Warnings
3
- Climbing on wet Fell Sandstone causes permanent, irreversible damage to holds and routes — the NMC ethic of 'Love the rocks' must take priority.
- Freeze-thaw damage is actively occurring at 280m altitude given recent overnight frosts and saturated rock; holds may be more fragile than usual even once the rock eventually dries.
- The surface may appear dry in sun/wind before the interior has dried — do not be deceived by surface appearance after such a prolonged wet period.
Reasoning
With 4.8mm falling today, 8.7mm in the last 7 days, and 42.2mm over the last 28 days with no sustained dry spell, the Fell Sandstone is almost certainly saturated well beyond the critical 1% threshold at which significant weakening begins.
Despite the exposed S/SW aspect and decent winds, there have been zero consecutive dry days heading into today — every brief dry interval has been interrupted by further rain, preventing the 48–72+ hours of dry weather needed after the heavier events.
At likely saturation levels, compressive strength could be reduced by 10–50% (average 32%), and the iron oxide cemented holds that characterise Great Wanney's routes are at serious risk of breakage — climbing now would risk permanent damage to irreplaceable routes.
Early April at 280m altitude brings overnight frosts (several nights below 0°C recently including -2.9°C on April 2nd and -2.8°C on April 6th), creating freeze-thaw cycling in moisture-laden rock that compounds structural weakening.
Contributing Factors
7
4.8mm of rain is falling today, directly wetting the rock surface and replenishing internal moisture reserves.
There have been zero consecutive dry days entering today, meaning the rock has had no opportunity to begin meaningful drying.
42.2mm over 28 days with frequent small events has kept the sandstone in a persistently moist state with no reset period.
Multiple overnight frosts in the past two weeks (down to -2.9°C) combined with likely internal moisture create active freeze-thaw damage conditions.
The south/south-west facing exposed aspect provides the best possible drying conditions for Northumberland sandstone, but this advantage is negated by continuous re-wetting.
Winds of 29–49 km/h in recent days accelerate surface evaporation, but cannot overcome the lack of any dry spell.
Average humidity of 75% over the last week limits evaporative drying capacity even when rain is not actively falling.
Recommendations
3
- Do not climb at Great Wanney today or in the coming days — the rock is wet and structurally compromised; wait for a sustained dry spell of at least 3 days with good winds before reassessing.
- Monitor the forecast beyond April 17th for the first window of 48–72+ consecutive dry hours with temperatures above 8°C and low humidity before planning a visit.
- Use the moorland approach as a condition indicator: if the walk-in is boggy and the crag base is damp, the rock is certainly too wet regardless of how the surface appears.
Do Not Climb
45%
4 days ago
Despite a dry day today and one yesterday, 1.9mm of rain fell on April 9th following a persistently wet spring pattern with 41.3mm over the past 28 days. With only one full dry day, the porous Fell Sandstone is very likely still holding internal moisture, and rain is forecast again tomorrow.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's exposed moorland position at 280m means strong SW/W winds do accelerate surface drying, but the 10–20m escarpment height means lower sections and crack systems will retain moisture longer than the wind-scoured upper faces.
- The boggy approach walk is a useful proxy for ground saturation — if the moorland is waterlogged (likely given 41mm in 28 days), the crag base and surrounding ground will confirm the rock is not fully dried.
- The S/SW aspect is favourable for spring drying with lengthening days, but April sun angles at 55°N latitude are still relatively low and solar heating is moderate at 280m altitude.
- Great Wanney's sandstone features many crack lines and horizontal breaks that trap and channel water internally, meaning even wind-exposed faces can harbour hidden moisture after the recent wet spell.
Warnings
3
- Freeze-thaw cycles are active at 280m with overnight lows near 0°C and saturated rock — climbing risks permanent hold breakage on irreplaceable routes.
- The rock surface may appear dry in the wind today while remaining dangerously weakened internally — do not be deceived by surface appearance.
- 7mm of heavy rain forecast for tomorrow will fully re-saturate the crag, negating any drying progress from today.
Reasoning
With 1.9mm of rain on April 9th following a prolonged wet spring (41.3mm in 28 days including 6.1mm on March 29th and 12.9mm on March 24th), the rock is almost certainly still damp internally despite one dry day.
Today's dry conditions with moderate SW wind (27.7 km/h) and low humidity (68%) are helpful for surface drying, but a single day is insufficient to dry porous Fell Sandstone after recent rain on a background of cumulative winter/spring moisture.
The combination of residual internal moisture and overnight temperatures dropping to 0.4°C today (and forecast -0.1°C tomorrow) creates active freeze-thaw risk at the critical saturation threshold, posing both hold breakage and permanent crag damage concerns.
Early April at 280m altitude in Northumberland is still a marginal season — short warm spells are interspersed with cold, wet fronts, and the cumulative winter moisture load means the rock has had very little opportunity to dry out thoroughly.
Contributing Factors
6
1.9mm of rain fell yesterday, and the minimum 24–48 hour drying guideline for light rain has not yet been met with only one dry day elapsed.
41.3mm over 28 days with frequent small precipitation events means the sandstone has had very few opportunities to fully dry, keeping internal saturation elevated.
Today is dry with 68% humidity and 27.7 km/h SW wind on an exposed S/SW-facing crag, providing reasonable surface drying conditions.
Overnight lows near or below 0°C (0.4°C today, -0.1°C forecast tomorrow) combined with likely internal moisture create active freeze-thaw damage risk.
7.0mm of rain is forecast for April 11th, which will completely reset any drying progress and re-saturate the rock.
Great Wanney's exposed moorland setting with consistent 20–35 km/h winds does accelerate surface evaporation compared to sheltered woodland crags.
Recommendations
3
- Do not climb today — the rock has had only one dry day since rain on April 9th, and the cumulative spring moisture means internal saturation is very likely still elevated.
- With 7mm of rain forecast tomorrow, the earliest realistic window would require at least 48–72 hours of dry weather after the next rain event passes, so monitor conditions closely from mid-next week.
- If visiting the area, use today to check the approach path and crag base — if the moorland is boggy and the crag foot damp, that confirms the rock is not ready.
Marginal — Assess Conditions
55%
5 days ago
The crag has had three fully dry days (April 6–8) with good temperatures and reasonable wind following the last significant rain on April 5 (2.0mm), but today (April 9) brings 0.8mm of light precipitation and high humidity, introducing fresh surface moisture. The S/SW aspect and exposed position have aided drying, but the cumulative wet March/early-April pattern and today's drizzle mean conditions should be verified on arrival.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's 10–20m escarpment faces S/SW on open moorland, giving it excellent solar exposure and wind drying — it is one of the faster-drying Fell Sandstone crags, but the 280m altitude means temperatures remain cool in early April.
- The walk-in across boggy moorland is a useful proxy indicator: if the approach ground is saturated and boggy, the rock is likely still holding internal moisture from the prolonged wet period.
- The crag's upper sections and steeper walls will have dried significantly faster than the base and any slab sections; seepage lines from the moorland plateau above can persist for days after rain.
- The 67mm of rain over the past 28 days represents a sustained wet period for porous Fell Sandstone, meaning deeper internal moisture may linger even where surfaces appear dry.
Warnings
2
- Do not climb if today's precipitation has visibly wetted the rock surface — even 0.8mm on porous Fell Sandstone causes rapid strength loss.
- The 67mm of rain over the past month means internal moisture levels may be higher than surface appearance suggests; holds that look dry could still be structurally weakened.
Reasoning
Three dry days (Apr 6–8) with warm temperatures (up to 16.7°C) and moderate wind provided good surface drying, but today's 0.8mm precipitation and 82% humidity will have re-wetted the surface, and the cumulative 67mm over 28 days suggests internal moisture may persist.
The S/SW aspect and exposed moorland setting significantly accelerate drying; the three warm dry days likely dried the upper and steeper sections well, but today's drizzle and the overnight humidity spike to 96% will have slowed or partially reversed surface drying.
Given the prolonged wet winter/spring pattern and overnight frost potential (min -2.8°C on Apr 6, near 0°C tonight), some freeze-thaw cycling may have occurred while the rock retained internal moisture, slightly elevating hold breakage risk.
Early April in Northumberland is transitional — daytime temperatures are improving but overnight frosts still occur, humidity remains high, and the rock may not have fully recovered from winter saturation.
Contributing Factors
6
April 6–8 were fully dry with the warmest day reaching 16.7°C, providing a solid drying window for this exposed S/SW crag.
Today (Apr 9) brings 0.8mm of rain with 82% humidity, re-wetting the surface and interrupting the drying sequence.
67mm over the past 28 days indicates a persistently wet period, meaning deeper pore saturation may linger despite surface drying.
The south/south-west facing open moorland setting maximises solar radiation and wind exposure, making Great Wanney one of the faster-drying Fell Sandstone venues.
Humidity rose to 93–96% overnight (Apr 8–9), likely depositing dew or condensation on rock surfaces and slowing the net drying rate.
Min temperatures are hovering near 0°C (tonight forecast at 1.9°C) — freeze-thaw risk is reducing but not yet eliminated at 280m altitude.
Recommendations
3
- Wait until later today or tomorrow when the wind picks up (forecast 27–38 km/h SW) and humidity drops to ~70% — if conditions feel dry on arrival, the upper steeper sections are most likely to be in condition.
- Check the base of the crag and any seepage lines before committing; if the ground at the crag foot is damp or holds feel chalky-soft, do not climb.
- Given the prolonged wet spring, favour the steeper, more overhanging lines which shed water fastest, and avoid slabby or lower-angle routes where moisture lingers.
Marginal — Assess Conditions
60%
6 days ago
Great Wanney has had two full dry days (April 6–7) with good conditions yesterday — warm temperatures up to 14.7°C, low humidity (45–50% midday), and moderate SE wind — following 2mm of rain on April 5. However, the broader picture shows frequent light precipitation through late March and early April, with 69mm over the past 28 days, meaning the rock may still hold residual internal moisture despite the surface appearing dry. Today's trace precipitation (0.3mm) is negligible but humidity remains moderate.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's south/south-west aspect and exposed moorland position mean it benefits strongly from yesterday's clear-sky sunshine and moderate wind, giving it above-average drying for Northumberland sandstone.
- The 20–30 minute boggy walk-in is a useful proxy — if the approach moorland is still waterlogged, the crag base is likely retaining moisture too.
- The escarpment's 10–20m height means lower sections will have dried more slowly than upper walls; base routes and slabs should be treated with extra caution.
- The cumulative 69mm over the past 28 days represents a significant moisture load for porous Fell Sandstone in early spring, and only two genuinely dry days may not be sufficient for full internal drying despite favourable surface conditions.
Warnings
2
- Recent freeze-thaw cycles on moisture-laden rock may have weakened surface holds — test holds carefully and be alert for loose or friable rock.
- The rock surface may appear dry while internal moisture persists from the prolonged wet period — do not assume surface appearance alone confirms safe conditions.
Reasoning
The last meaningful rain was 2.0mm on April 5, preceded by frequent light showers through late March and early April totalling 69mm over 28 days — internal moisture levels in this porous sandstone are likely still elevated despite two dry days.
Two dry days with excellent conditions yesterday (14.7°C, 45% humidity, moderate wind, clear skies on a S/SW-facing exposed crag) will have significantly dried the surface, but the community standard of two dry days after light rain is only marginally met given the prolonged wet background.
Overnight lows near or below 0°C on several recent nights (April 2: -2.9°C, April 4: -1.1°C, April 5: -0.9°C, April 6: -2.8°C) combined with residual moisture create freeze-thaw cycling risk that may have weakened surface holds.
Early April in Northumberland at 280m is still marginal for reliable drying — temperatures are cool, days are lengthening but solar angle remains low, and the prolonged winter/early spring moisture load takes time to dissipate.
Contributing Factors
6
April 6 and 7 were essentially dry (0.0mm each), meeting the minimum two-day rule after the last light rain of 2.0mm on April 5.
Yesterday saw 14.7°C, humidity dropping to 45%, clear skies, and 24 km/h SE wind — outstanding drying conditions for an exposed S/SW-facing crag.
69mm over 28 days with very few consecutive dry days means the sandstone has been repeatedly re-wetted, and internal moisture may persist despite surface drying.
Several nights in the past week dropped below 0°C (down to -2.9°C on April 2) while the rock likely still held internal moisture, risking cumulative structural weakening.
Today's 78% humidity and 0.3mm trace precipitation are unlikely to significantly re-wet the rock but will slow further drying compared to yesterday.
Great Wanney's exposed moorland position and south-facing aspect maximise wind and solar drying, making it one of the faster-drying Fell Sandstone crags.
Recommendations
3
- Visit the crag and carefully assess conditions on arrival — check the base of the crag and lower routes for any signs of dampness or dark patches before committing to climb.
- Prioritise upper-wall and overhanging routes which will have dried fastest; avoid slab routes and lower sections where moisture persists longest.
- If the approach moorland is very boggy or the rock base feels cool and damp to the touch, err on the side of caution and do not climb.
Do Not Climb
45%
8 days ago
Although today is dry with improving conditions, the crag received 2.0mm of rain yesterday (April 5th) on top of a very wet recent period (69.2mm in 28 days, including 6.1mm on March 29th, 12.9mm on March 24th, and 27mm on March 12th), and only one full dry day has elapsed — insufficient drying time for porous Fell Sandstone that has been repeatedly saturated through late winter and early spring. The rock is likely still holding significant internal moisture despite the exposed, south-facing aspect and reasonable winds.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's 10–20m escarpment means the lower sections will retain moisture longest, with water draining downward through the porous sandstone from the heavily saturated moorland above.
- The walk-in is described as 'boggy in places' — if the approach is waterlogged, the surrounding ground moisture confirms the rock is unlikely to have dried internally.
- The exposed moorland setting at 280m means overnight frost (min -0.7°C today) on recently wetted rock creates freeze-thaw risk, potentially weakening holds on a crag where many routes already test their grade.
- The S/SW aspect and exposed position are favourable for drying, but the persistent high humidity (82% average over the last 7 days) has significantly limited evaporative drying potential.
Warnings
2
- Do not climb today — only one dry day after repeated wetting is far too soon for Fell Sandstone that has absorbed nearly 70mm of rain in the past month.
- Overnight frost on saturated sandstone creates active freeze-thaw damage conditions; climbing on weakened holds risks both personal injury and irreversible crag damage.
Reasoning
With 2.0mm falling yesterday, 3.2mm the day before, 3.5mm on April 3rd, and a cumulative 69.2mm over 28 days, the sandstone has been repeatedly re-wetted and is very likely saturated internally despite only one dry day since the last rain.
Only one dry day has elapsed since the last meaningful rain (2.0mm on April 5th), and while today's conditions are favourable (71% humidity, S wind, 11.2°C), a single day is well below the minimum 24–48 hours needed even for light rain — and the cumulative saturation from repeated wetting events demands much longer.
The repeated wetting-drying-freezing cycle through March (with overnight frosts to -3.3°C on saturated rock) raises significant concern about cumulative freeze-thaw damage and hold integrity, particularly on the iron oxide holds characteristic of Fell Sandstone.
Early April in Northumberland at 280m is still firmly in the vulnerable transition period — overnight frosts are common, days are short relative to summer, and the prolonged wet winter means deep moisture reserves persist in the rock.
Contributing Factors
7
2.0mm fell on April 5th with only one dry day since, far short of the minimum 24–48 hour drying window even for light rain on porous sandstone.
69.2mm over the past 28 days with frequent re-wetting events means the sandstone has had no opportunity to dry out internally, maintaining high pore saturation.
The S/SW aspect and exposed moorland position maximise solar radiation and wind exposure, giving Great Wanney above-average drying potential compared to sheltered or north-facing crags.
Today's 0.0mm precipitation, 71% humidity, and 11.2°C represent the best drying conditions in several days, though one day alone is insufficient.
Average humidity of 82% over the past 7 days has severely limited evaporative drying, keeping the rock wetter than temperature and wind alone would suggest.
Overnight temperatures dropping to -0.7°C on recently wetted rock at 280m altitude create active freeze-thaw conditions that damage saturated Fell Sandstone.
Winds of 34–49 km/h over recent days have aided surface drying, though they cannot overcome the deep saturation from repeated heavy rain.
Recommendations
3
- Wait for at least 48–72 hours of continuous dry weather before visiting; the current one dry day is insufficient given the cumulative saturation.
- Check the bogginess of the approach path as a proxy for ground and rock moisture — if the walk-in is waterlogged, the rock will not be dry.
- If you do visit later this week after further dry days, test the base of the crag with the back of your hand and check for any darkened (damp) patches before committing to climb.
Do Not Climb
30%
9 days ago
Great Wanney has received repeated precipitation over the past two weeks including 6.1mm on March 29, 3.5mm on April 3, 3.2mm on April 4, and 1.6mm today (April 5), with no consecutive dry days. Despite strong winds today, the cumulative moisture loading on this porous Fell Sandstone through a wet late-winter/early-spring period means internal saturation is likely still high and climbing should be avoided.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's 10–20m escarpment means the upper sections may dry faster than the base, but persistent seepage from the moorland plateau above can keep lower routes damp for extended periods after wet spells.
- The 20–30 minute boggy walk-in is itself a useful moisture indicator — if the approach is waterlogged, the crag is almost certainly still holding internal moisture.
- The south/south-west aspect and exposed moorland setting are the crag's main drying advantages, but at 280m altitude the cooler spring temperatures (averaging only 4.8°C this past week) significantly slow evaporation.
- The iron oxide deposits that form many of the small holds at Great Wanney are particularly vulnerable to grain loosening when the sandstone is internally saturated — hold breakage risk is elevated after this prolonged wet period.
Warnings
3
- Fell Sandstone loses up to 50% of its compressive strength when wet — holds can snap without warning, risking serious injury and permanent crag damage.
- Freeze-thaw cycling on saturated rock has likely weakened surface features over recent weeks; even holds that felt solid last season may now be compromised.
- The rock surface may appear dry in the strong wind while remaining dangerously saturated internally — do not be deceived by surface appearance alone.
Reasoning
With 68.8mm over 28 days, rain on each of the last three days (3.5mm, 3.2mm, 1.6mm), and zero consecutive dry days, the rock is almost certainly saturated internally despite any surface drying from today's strong winds.
Today's 49 km/h westerly wind and 70% humidity will help surface drying, but the S/SW-facing aspect receives limited benefit from a westerly wind direction, and the cumulative moisture from weeks of intermittent rain requires far more than a few hours to clear from porous Fell Sandstone.
With repeated wetting over the past month and overnight temperatures dropping below freezing on several recent nights (including -1.1°C last night and -2.9°C on April 2), freeze-thaw cycling on saturated rock poses a significant risk of hold breakage and structural damage.
Early April at 280m altitude is still firmly in the vulnerable spring transition period, with low average temperatures (4.8°C), high humidity (82% average), and minimal solar intensity — conditions that dramatically slow the deep drying that Fell Sandstone requires.
Contributing Factors
7
Rain fell on April 3 (3.5mm), April 4 (3.2mm), and today April 5 (1.6mm), with no consecutive dry days and 9.7mm in the past week alone — the rock has had no opportunity to begin meaningful drying.
68.8mm over 28 days including a 27mm event on March 12 and 12.9mm on March 24 means the sandstone has been repeatedly re-saturated throughout the period, maintaining high internal moisture levels.
Today's 49 km/h westerly wind at 70% humidity will accelerate surface evaporation, but this alone cannot dry the interior of porous sandstone that has been repeatedly wetted.
Average temperature of only 4.8°C over the past week with overnight lows near or below freezing severely limits evaporation rates and extends required drying times.
Multiple recent freeze-thaw cycles (min temps of -2.9°C, -1.1°C, 0.3°C in recent days while rock remains saturated) increase the risk of structural damage, particularly as pore saturation likely exceeds the critical 60% threshold.
The south/south-west facing aspect and exposed moorland position are advantageous for drying, but spring solar angles and cool temperatures limit the benefit at this time of year.
Average humidity of 82% over the past week significantly slows net evaporation from the rock surface, prolonging internal drying times well beyond what temperature and wind alone would suggest.
Recommendations
3
- Do not climb today — wait for at least 48–72 hours of genuinely dry weather with low humidity before considering a visit.
- Monitor the forecast window of April 6–8 which shows zero precipitation and warming temperatures; if this holds, conditions may become assessable by April 8.
- On arrival, check whether the approach path is boggy and whether the base of the crag feels damp — if either is true, the rock is certainly still too wet internally to climb safely.
Do Not Climb
70%
10 days ago
Great Wanney has received frequent precipitation over the past month (66.4mm in 28 days) with no consecutive dry days leading into today, which itself has 2.4mm of rain. Despite the exposed, south-facing aspect and strong winds aiding drying, the porous Fell Sandstone has had no meaningful dry spell to recover, and conditions today are clearly unsuitable — the rock should not be climbed.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's 10–20m escarpment means the upper sections will dry faster than the base, but after persistent wet weather the entire face is likely holding moisture internally.
- The boggy moorland approach is a useful proxy — if the ground is waterlogged on the walk-in, the rock is almost certainly still damp internally.
- The crag's exposed position at 280m means the strong SW/W winds (consistently 20–44 km/h) are hitting the face directly, which is the single most favourable drying factor in an otherwise poor picture.
- Seepage lines and cracks on this sandstone escarpment will hold moisture far longer than the face; even when surfaces appear dry, water can weep from horizontal breaks for days after heavy rain.
Warnings
3
- Climbing on wet Fell Sandstone causes permanent, irreversible damage to holds and routes — the NMC ethic of 'Love the rocks' must take priority.
- Freeze-thaw cycling with overnight sub-zero temperatures on saturated rock compounds structural risk — even holds that feel dry may be critically weakened internally.
- The approach path will be very boggy after recent rain; plan for slow going and appropriate footwear.
Reasoning
With 13.4mm in the last 7 days including rain today (2.4mm) and yesterday (3.5mm), plus 66.4mm over 28 days with zero consecutive dry days, the rock is almost certainly saturated internally despite any surface drying.
The south/south-west aspect and strong winds (43.9 km/h today) are highly favourable for surface drying, but with rain falling today and yesterday there has been no meaningful drying window — the rock needs at least 48–72 hours of dry weather from the last significant wetting.
At current likely saturation levels, Fell Sandstone could be experiencing 10–50% compressive strength loss; climbing risks hold breakage and permanent route damage, especially on the iron-oxide-cemented small holds this crag is known for.
Early spring at 280m altitude with overnight temperatures dropping below 0°C (min -0.1°C today) introduces freeze-thaw risk on saturated rock, compounding the structural vulnerability.
Contributing Factors
7
66.4mm over 28 days with no consecutive dry days and rain today (2.4mm) and yesterday (3.5mm) means the rock has had no opportunity to dry internally.
Sustained SW/W winds of 20–44 km/h hitting the south-facing aspect directly are the most significant drying aid, accelerating surface evaporation considerably.
The S/SW aspect at this exposed moorland site receives good solar radiation and direct wind, giving it above-average drying potential compared to sheltered or north-facing crags.
Average humidity of 83% over the last 7 days significantly reduces the drying rate, as moist air limits net evaporation from the rock surface.
Overnight temperatures dropping to -0.1°C today and below 0°C on several recent nights create freeze-thaw cycling in rock that is likely above the 60% critical saturation threshold.
The complete absence of any multi-day dry spell means drying has been repeatedly interrupted, preventing the rock from losing internal moisture even if surfaces occasionally dry.
Average temperature of 5.0°C over the last week provides limited thermal energy for evaporation, slowing the drying process considerably compared to summer conditions.
Recommendations
3
- Do not climb today — the rock has had no dry spell after persistent rain and is very likely damp internally despite the strong winds.
- Monitor the forecast: if the predicted dry window from April 6–8 materialises (0mm rain, warming to 16.6°C, moderate winds), conditions could become climbable by April 7 or 8 — check the base of the crag for dampness before committing.
- Use the boggy moorland walk-in as a condition indicator: if the ground is waterlogged and puddles persist, the sandstone is almost certainly still holding moisture.
Do Not Climb
90%
11 days ago
Great Wanney received 2.4mm of rain today on top of a persistently wet spring pattern — 65.7mm in the last 28 days with no meaningful dry spell. The rock is almost certainly wet internally despite any surface drying, and climbing today would risk both hold breakage and permanent crag damage.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Great Wanney's 10–20m escarpment means the lower sections will retain moisture longest, with water draining downward through the porous sandstone long after the upper face appears dry.
- The boggy moorland approach and surrounding saturated ground at 280m altitude reflect the generally waterlogged state of the area — if the walk-in is boggy, the rock is almost certainly still holding moisture.
- The S/SW aspect and exposed position are helpful for drying, but March into early April has had repeated rain events (27mm on Mar 12, 12.9mm on Mar 24, 6.1mm on Mar 29, plus today's 2.4mm) preventing any sustained drying period.
- Freeze-thaw risk is elevated: overnight temperatures have dropped below zero frequently (as recently as Apr 2 at -2.9°C), and the rock is likely above the 60% critical saturation threshold given the cumulative rainfall.
Warnings
3
- Climbing on wet Fell Sandstone causes permanent, irreversible damage to holds — the iron oxide cemented features that define Great Wanney's routes cannot be replaced.
- Freeze-thaw damage risk is elevated: sub-zero overnight temperatures combined with saturated rock can cause hidden structural weakening and sudden hold failure.
- The NMC ethic of 'Love the rocks' places rock conservation above all else — climbing on damp sandstone violates this fundamental principle.
Reasoning
With 2.4mm of rain today, 6.1mm on March 29, and no consecutive dry spell longer than about 5 days in the past month — all atop 65.7mm total in 28 days — the sandstone is almost certainly saturated well beyond the surface.
Although the SW-facing aspect and exposed position with moderate winds (20–35 km/h) provide above-average drying potential, there has been zero consecutive dry days as of today and the repeated wetting events have never allowed sufficient 48–72+ hour drying windows since the heavy rain on March 12 and March 24.
The combination of high internal moisture and repeated freeze-thaw cycles (multiple nights below 0°C in the past two weeks, including -2.9°C on April 2) creates serious risk of hold breakage and grain loosening on these iron oxide–cemented holds.
Early April at 280m altitude in Northumberland is still firmly in the vulnerable transition period — short days, low sun angles, cool temperatures averaging under 5°C recently, and high ambient humidity (82% average) all conspire to keep drying rates slow.
Contributing Factors
7
Fresh rain today means the rock surface is currently wet and internal moisture is being topped up, resetting any drying progress.
65.7mm over 28 days with no sustained dry spell means the sandstone has been repeatedly re-saturated and is likely holding significant internal moisture.
Overnight temperatures have dropped below 0°C on multiple recent nights (including -2.9°C on April 2), and with the rock likely above 60% saturation, freeze-thaw damage risk is high.
The south/south-west facing, exposed moorland position gives Great Wanney above-average drying potential when dry weather does arrive.
Average humidity of 82% over the past week significantly slows evaporation from the rock surface, extending drying times well beyond minimum guidelines.
Winds have been consistently moderate to strong (20–35 km/h) which helps move moist air away from the rock face and accelerates surface drying.
Average temperatures under 5°C over the past week slow evaporation considerably, meaning drying takes substantially longer than summer conditions.
Recommendations
3
- Do not climb today — the rock is wet from today's rain and deeply saturated from the persistent wet pattern this spring.
- Wait for a sustained dry spell of at least 3 days (ideally 4–5 given cumulative saturation) with wind and temperatures above 8°C before considering a visit.
- On arrival after a dry spell, check the ground at the crag base: if the soil or sand is damp, the rock is still holding internal moisture and should not be climbed.
Climbing Outlook