West Pacific (RPCA daily)

CPC-method rotated-PCA West Pacific pattern rebuilt from ERA5 500-hPa height, daily least-squares fit on patterns interpolated to the day. Positive: low over Kamchatka, high over south-east Asia and the western subtropical North Pacific (opposite in sign to the Wallace–Gutzler WP). — Barnston & Livezey 1987; NOAA CPC