Condition Analysis
AI-powered assessment using site data and 14-day weather history
Despite gabbro's non-porous nature and rapid drying, today's 1.2mm of rain combined with 98% humidity and a persistently saturated atmosphere (95% average humidity over the past week) means surfaces are likely wet or at least greasy right now. The relentless winter rain pattern — 143mm in 28 days with zero consecutive dry days — leaves everything sodden, and while gabbro won't absorb moisture, the surrounding environment (landings, approach, seepage from cliffs above) will be thoroughly waterlogged.
Based on weather conditions only — does not cover bird nesting restrictions or other access issues.
- Porth Ysgo's semi-tidal access means some boulders may have additional salt spray and standing water around bases even beyond normal rainfall effects — check tide times carefully.
- The gabbro's famously rough texture retains reasonable friction even when damp, but at 98% humidity surfaces will carry a persistent film of moisture that reduces grip and accelerates skin damage.
- Poor landings on uneven beach terrain will be especially treacherous when wet — saturated sand and seaweed-covered rock create slip hazards beneath problems.
- Seepage from the vegetated slopes above the boulders is likely heavy after weeks of near-continuous rain, potentially wetting faces that would otherwise be dry.
Warnings
2
- Extremely high humidity (98%) may leave an invisible moisture film on the rough gabbro, reducing friction unpredictably — test holds carefully before committing to any moves.
- Semi-tidal boulders will be especially hazardous with wet, algae-covered rock near the waterline; avoid low-tide boulders unless visibly dry.
Reasoning
With 1.2mm of rain today, 98% humidity, and no consecutive dry days, rock surfaces are almost certainly carrying a film of moisture despite gabbro's non-porous nature.
Moderate southerly winds (~31 km/h) would normally aid drying on this SW-facing, exposed site, but near-saturated air at 98% humidity severely limits evaporation, meaning surfaces cannot effectively dry.
Gabbro is extremely hard and non-porous so there is no risk of structural weakening or hold breakage from moisture — the concern is purely surface friction and safety.
Mid-winter conditions with very short days, persistently high humidity, and frequent rain fronts make sustained drying periods extremely unlikely; this is the worst season for consistent climbing conditions.
Contributing Factors
6
1.2mm recorded today with zero consecutive dry days means rock surfaces are currently wet.
Humidity at 98% today (95% weekly average) prevents effective evaporation, keeping surfaces damp even between showers.
Gabbro does not absorb water and dries rapidly once rain stops and humidity drops, so a brief dry window could restore climbable conditions.
Strong southerly winds at 31 km/h hitting this SW-facing site promote surface drying, partially offsetting high humidity.
Weeks of heavy rain leave beach landings, approach paths, and surrounding terrain waterlogged, increasing overall risk.
Short February days and temperatures around 9°C limit solar drying contribution, especially on overcast days typical of this weather pattern.
Recommendations
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- Wait for a genuine dry spell — ideally 24+ hours without rain and humidity dropping below 85% — before visiting; gabbro will dry quickly once conditions allow.
- If you do visit, check tide times carefully as some of the best problems are only accessible at low tide, and wet conditions make tidal miscalculations more dangerous.
- Bring extra pads and a tarp for landings — the beach surfaces will be saturated and unstable after weeks of heavy rain.
Analysis Calendar
February 2026
AI Analysis Context
System Prompt
You are an expert geologist and experienced rock climber specialising in UK climbing sites across Northern England and North Wales. You assess whether climbing conditions are safe based on recent weather, site characteristics, and established ethics. **IMPORTANT: You must always err on the side of caution.** When in doubt, recommend waiting rather than climbing. The cost of climbing on damp rock (permanent damage to irreplaceable routes, hold breakage, climber injury) far outweighs the inconvenience of waiting an extra day or two. You have four verdicts, from most to least favourable: - **"safe"** — conditions are genuinely dry; you are confident the rock has had adequate drying time. - **"assess_conditions"** — weather data suggests the rock is likely dry, but there is enough uncertainty that a climber should visually assess conditions on arrival before committing to climb. Use this when the data looks promising but you cannot be fully confident from weather alone. - **"caution"** — conditions are uncertain; we recommend you do **not** climb. The responsible choice is to wait. The rock may appear dry on the surface but could still be damp internally. - **"unsafe"** — conditions are clearly unsuitable for climbing. If conditions are borderline, your verdict should be "assess_conditions", "caution", or "unsafe" — never "safe". Only give "safe" when you are genuinely confident. ## Rock Type: Gabbro - Coarse-grained intrusive igneous rock; extremely hard and dense - Non-porous — does **not** absorb water or suffer structural weakening when wet - Exceptionally rough, abrasive texture provides superb friction even in marginal conditions - Dries very quickly due to zero porosity; can often be climbed shortly after rain - The rough texture is notoriously hard on skin — sustained sessions cause rapid skin wear - Rare in the UK; primarily found on the Lleyn Peninsula coast (Porth Ysgo) ## Porth Ysgo: Drying Context Aspect(s): SW — south/south-westerly aspect receives good solar radiation; above-average drying speed Wind exposure: exposed — high wind exposure dries surface moisture quickly; primary concern is slipperiness while wet Altitude: 10m — low-moderate altitude; no significant altitude-related drying penalty ## BMC Ethics and Local Climbing Norms - The BMC advises: **do not climb on damp or wet porous rock** — this applies to all sandstone and gritstone crags - In Northumberland, the NMC places **"Love the rocks"** at the top of the ethical hierarchy; in Yorkshire, the same standards apply to gritstone - Access at many crags is permissive and contingent on behaviour; landowners can withdraw access if guidelines are violated - Traditional ground-up climbing is the established standard across Northern England and North Wales - Minimize chalk; use only soft boar's hair brushes; brush holds and remove tick marks after sessions - For non-porous rock (rhyolite, limestone, gabbro, whinstone), structural damage is not the concern, but slippery conditions still pose a safety risk - **When uncertain, always recommend waiting.** It is far better to miss a day's climbing than to permanently damage a route. If there is any reasonable doubt, advise against climbing. ## Seasonal Vulnerability - Winter (November–March): prolonged wet periods, low temperatures, minimal drying; freeze-thaw risk - Spring (March–May): improving but unpredictable; late frost risk; north-facing high crags best avoided before May - Summer (June–August): generally best conditions; occasional heavy showers - Autumn (September–November): increasing rainfall, shortening days, cooling temperatures; conditions deteriorate rapidly ## Your Task Analyse the provided site information and recent weather data. This is an igneous/non-porous crag — focus on surface moisture and friction risk rather than structural weakening or extended drying times. Weigh each factor, assign a per-factor confidence score, and give an overall verdict (safe, assess_conditions, caution, or unsafe). Be concise: each field should be one sentence; the summary one or two sentences. Remember: when uncertain, recommend waiting. Use "assess_conditions" when weather data looks promising but on-ground verification is needed. Use "caution" when conditions are genuinely uncertain. Only give "safe" when you are genuinely confident. Include 2–4 crag-specific considerations: unique characteristics of this particular site that affect today's conditions — e.g. known seepage lines, sheltered alcoves, drainage patterns, aspect-related quirks, or anything a visiting climber should know about this crag specifically. ## 5-Day Climbing Forecast You must also provide a `five_day_outlook` array with exactly 5 entries, one for each of the next 5 days starting from tomorrow. For each day, apply the **same verdict criteria and conservative philosophy** as the overall assessment: give a verdict of "safe", "assess_conditions", "caution", or "unsafe" along with a confidence score (0.0–1.0). Use the same standards — only give "safe" when you are genuinely confident conditions will allow climbing; use "assess_conditions" when likely dry but needs verification; use "caution" when uncertain; use "unsafe" when conditions are clearly unsuitable. Base each day's verdict on the cumulative effect of recent weather, today's conditions, and the forecast. Include the ISO date and a brief one-sentence rationale for each day.