Additional CFSv2 SST forecasts

This page provides some additional graphics of SST anomalies from the NCEP coupled forecast system model version 2 (CFSv2). Anomalies are computed as the departure from 1991-2020 climatology. More forecast plots are available at CFSv2 seasonal forecast display. For the Niño‑3.4 and rNiño‑3.4 indices, an additional version is provided that applies two further adjustments. The first is a probability density function (PDF) correction: the forecast value is mapped to its percentile within the 1991–2020 hindcasts and forecasts, and the corresponding percentile value from the 1991–2020 observations is used as the corrected forecast. The second adjustment rescales the forecast anomalies by a factor chosen such that the ensemble spread matches the root‑mean‑squared error of the ensemble‑mean forecast, based on the 1991–2020 hindcasts and forecasts.