This shows probably the best
skill for IOD prediction which current coupled models may achieve. Starting
from each month January 1st, February 1st, March 1st, the skill
decrease gradually and reach minimum values in December. This is related to
the strong phase locking with monsoon. The skill then rebound and decrease
quickly in next spring. This part is associated with ENSO influences. So you
can see both winter and spring barrier exist in eastern pole prediction .In
general, the signal can be predicted up to about 2 seasons ahead.