El Niño/La Niña Update (November 2021)

La Niña conditions have developed in the tropical Pacific, with both oceanic and atmospheric indicators reaching the necessary thresholds during the SeptemberOctober 2021 period. The latest forecasts from the WMO Global Producing Centres of Long-Range Forecasts indicate a high chance (90%) of tropical Pacific sea surface temperatures remaining at La Niña levels until the end of 2021, and a moderate chance (70-80%) for them to persist at La Niña levels through the first quarter of 2022. Most models indicate that the 2021/2022 La Niña is likely to be a weak-to-moderate event. National Meteorological and Hydrological Services (NMHSs) will closely monitor changes in the state of El Niño/Southern Oscillation (ENSO) over the coming months and provide updated outlooks.