Dynamic Models: While the dynamic models agree that in the very near term (1 season) conditions will remain relatively cold in the tropical Pacific, the forecasts for the decay of the current La Niña differ substantially. For example, both COLA models, both LDEO models and the BMRC model call for cold conditions to persist at least through early or middle 2000. On the other hand, the SIO, UCLA and NCEP models forecast a rapid return to normal over the next 2-3 seasons.

Statistical Models: The statistical models (linear inverse model, neural network model, CLIPER model, constructed analogue model, singular spectrum analysis model, Markov model) are predicting that the current La Niña will evolve similar to the forecasts produced by the COLA, LDEO and BMRC models. The linear inverse model is predicting the continued decay of the warm Caribbean and north tropical Atlantic SSTA.

For Land Surface Temperature and Precipitation 

Dynamic Models: With persisted SSTA, the regional spectral model forecasts increased fire potential and dry soil content for the western U.S. over the next 1-2 months. The NCEP AGCM forecast using predicted SSTA in the tropical Pacific calls for warm and dry conditions over much of the U.S. and southern Canada through summer 1999. The CPTEC AGCM March-May (MAM) 1999 Nordeste forecast using predicted SSTA in the Pacific and Atlantic calls for near normal rainfall. In contrast, the UKMO AGCM with persisted SSTA (from January) predicts a relatively wet rainy season for much of northeastern Brazil during MAM 1999. This difference may be due to the fact that persisted SST in the Pacific is much colder than the NCEP forecasted SSTA. The NCEP predicted SSTA is used in the CPTEC forecast.

Statistical Models: The linear regression forecast for U.S. surface temperature and precipitation for AMJ 1999 is for warm conditions in the west, cool conditions in the plains and dry conditions in much of Texas. During JAS 1999 the forecast is for warm conditions in the Pacific northwest and desert southwest and cool conditions in the Ohio valley, Great Lakes region and the Mid-Atlantic states. The CCA forecast for AMJ 1999 over Canada calls for warm conditions in the Northwest portion of the country. The multiple regression and descriminant analysis forecasts a wet rainy season in the Nordeste which agrees with the UKMO AGCM forecast, but contrasts the CPTEC AGCM forecast. The CCA forecast for Sahel rainfall calls for slight below normal precipitation during JAS 1999. The statistical forecast for Uruguay call for dry conditions throughout the country during the March to July 1999 period.