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FORECAST CONTEXT

DATA THROUGH 2026-10-12 · UPDATED 2026-10-13 11:02 UTC

ERA5 + GFS2.5°DAILY
BriefingWeather regimesWeather regimes
WR_EAT4W_NAOp

NAO+ · EAT4W

Projection index I_wr onto the NAO+ mean pattern (Euro-Atlantic regimes (ECMWF, Oct–Apr)): standardized area-weighted projection of the normalised anomaly field. — Ferranti, Corti & Janousek 2015 (QJRMS 141, 916)