Our seasonal forecasts are issued on the 20th of each month. In the case that the 20th falls on a weekend or national holiday, they are issued on the closest workday.
The APCC seasonal forecast is produced through a multi-model ensemble method, utilizing climate models from 14 climate forecasting centers and institutions in 10 countries around the world. Our forecast information should be used for reference only. Please consult the respective country’s national meteorological service for the official seasonal forecast for that country.
Sea Surface Temperature and ENSO Outlook
for December 2020 - May 2021
(Issued: 20 Nov, 2020)
The APCC ENSO Outlook suggests “La Niña ALERT”. The prevailing ENSO phase is expected to be negative. Negative SST anomalies along the equatorial Pacific are predicted during December 2020 – May 2021. Along with these spatial distributions, all of nine dynamical coupled models predict negative Niño3.4 index for the whole forecast period. As a result, the Niño3.4 index from multi-model ensemble is expected to be around -1.5℃ and gradually increase to -0.6℃. In summary, based on the running 3-month mean Niño3.4 index, the APCC ENSO outlook suggests strong La Niña (~49% probability) for December 2020 to February 2021 and the probability for the La Niña conditions is likely to decrease for March to May 2021, when its intensity is expected to turn to a weak La Niña (~34% probability)
