The 14-day forecasts are compiled from several numerical weather models — the Met Office UKV (UK), ECMWF (European) and GFS (American) — with statistical correction against local observations. Reliability: ~85% for days 1-3, ~70% for days 4-7, ~55% for days 8-14. For days 15-30 we synthesise using 1991-2020 climate averages, see
the long-range forecast.