La Niña conditions have returned and are expected to gradually strengthen and continue into the Northern Hemisphere winter 2011-12, reports the National Oceanic and Atmospheric Administration (NOAA).

La Niña conditions returned in August 2011 due to the strengthening of negative sea surface temperature (SST) anomalies across the eastern half of the equatorial Pacific Ocean.  While it is not yet clear what the ultimate strength of this La Niña will be, La Niña conditions have returned and are expected to gradually strengthen and continue into the Northern Hemisphere winter 2011-12.

See  El Niño/La Niña Current Conditions and Expert Discussions on the Climate Prediction Center web site for updates.