El Nino Southern Oscillation (ENSO) returning to neutral or La Nina conditions are equally likely into May-June 2011.

La Nina persisted during January 2011 as reflected by well below-average sea surface (-1.0 to -1.5 deg C) temperatures across much of the equatorial Pacific Ocean. However, some weakening was evident in certain atmospheric and oceanic anomalies.

Nearly all of the ENSO model forecasts weaken La Nina in the coming months. The majority of the models predict a return to a ENSO-neutal conditions by May-June 2011.

However, expect La Nina impacts to continue during February-April 2011. Above-average precipitation will continue due to an active storm trace over southern Idaho, northern Utah and the Rockies of Colorado.