Multiweek Blocking Skill

For a climatological forecast of the blocking index the RMSE=1, and thus forecasts are typically deemed to be skilful for RMSE < 1. POAMA-2 provides skill out to about 16 days, an improvement of about 1 week compared to POAMA-1.5.

Root-mean-square error of the predicted blocking index for the ensemble mean POAMA-2

Root-mean-square error of the predicted blocking index for the ensemble mean POAMA-2 (solid) and POAMA-1.5 (dashed) hindcast as a function of lead time (days), for hindcasts initialized 1980-2006.

Blocking correlation skill for the ensemble mean POAMA-2

Blocking correlation skill for the ensemble mean POAMA-2 (solid) and POAMA-1.5 (dashed) hindcast as a function of lead time (days), for hindcasts initialized 1980-2006.