IRI Home

Current ENSO Information

ENSO Quick Look
IRI ENSO Update
Technical ENSO Update
Summary of Model Forecasts

Summary of ENSO Model Forecasts

15 January 2004

> Note on interpreting model forecasts
> Discussion of current forecasts
> Figure of Nino3.4 SST forecasts
> Table of Nino3.4 SST forecasts
> Notes on the data

Note on interpreting model forecasts

The following graph and table show forecasts made by dynamical and statistical models for SST in the Nino 3.4 region for nine overlapping 3-month periods. Note that the expected skills of the models, based on historical performance, are not equal to one another. The skills also generally decrease as the lead time increases. Thirdly, forecasts made at some times of the year generally have higher skill than forecasts made at other times of the year--namely, they are better when made between June and December than when they are made between February and May. Differences among the forecasts of the models reflect both differences in model design, and actual uncertainty in the forecast of the possible future SST scenario. 

Discussion of current forecasts

The set of dynamical and statistical model forecasts issued during late December 2003 and early January 2004 shows a  range of possible sea surface temperature conditions for the coming 2 to 10 months (January - February - March 2004 through  September -  October - November 2004). Most models are indicating slightly above average conditions over the coming several months. Some of their positive anomalies are not far enough above average to be considered an El Nino, while others are far enough above to indicate weak El Nino conditions.