28 May 2026
Why Climbing Forecasts Uses Rain Radar
Climbing Forecasts uses rain radar data to help analyse recent rainfall around crags across the UK.
Rainfall is one of the most important factors affecting climbing conditions, particularly on rock types and locations that are sensitive to seepage, slow drying, humidity, or short periods of heavy rain.
There are two main ways to observe rainfall:
- Weather station observations
- Weather radar
Weather stations measure rainfall at a single physical location using rain gauges and other instruments. These observations are highly accurate for that specific point.
Weather radar works differently. The UK Met Office radar network regularly scans the atmosphere and produces rainfall estimates across a large spatial grid covering the UK.
Climbing Forecasts uses Met Office radar data because it allows recent rainfall to be analysed directly over individual crag locations rather than relying only on the nearest weather station.
This is useful because rainfall can vary significantly over relatively short distances, especially during local showers or coastal weather systems. In many climbing areas, the nearest official observation station may also be several kilometres from the crag itself and at a different elevation or exposure.
Radar data provides broader spatial coverage and allows Climbing Forecasts to build a recent rainfall picture around each crag location.
The radar data is not used in isolation. Climbing Forecasts combines it with forecast weather data and crag-specific metadata such as rock type, aspect, drying speed, seepage sensitivity, coastal exposure, and wind exposure.
The rain radar history panel summarises recent rainfall near a crag, including accumulation, peak intensity, duration, and nearest detected rain.
Weather radar also has limitations. Radar rainfall estimates are not exact ground measurements and can sometimes overestimate or underestimate rainfall in certain conditions. For this reason, radar data should be treated as an estimate of recent rainfall rather than an exact measurement.
Climbing Forecasts currently uses UK Met Office weather radar data as one input in its broader approach to analysing climbing conditions across UK crags.
References
For more detail on the UK Weather Radar Network, see the Met Office's information on radar systems and weather radar network renewal.