ECMWF is most aggressive with the ongoing rains in Southeast/East Brazil. The outlook is supported by ongoing negative Antarctic oscillation (-AAO) which implies semi-permanent low-pressure troughs in the middle latitudes. ECMWF projects a semi-permanent low-pressure trough east of Argentina located across an area of relative cool SSTA. Meanwhile, east of Brazil, a marine heat wave (MHW) is expected to strengthen. The upper trough entrains increased low-level atmosphere moisture across the MHW driving a wetter Southeast/East Brazil climate likely to last through spring.

The best initialization and consequently seasonal (SEP/OCT/NOV 2026) outlook of global SSTA is provided by the National Multi-model Ensemble. Of course, El Nino is vividly apparent in the eastern equatorial Pacific Ocean fueled by the warmest upper ocean heat on record. Most dynamic Nino34 SSTA forecasts maintain record-strength El Nino by mid-to-late Q4/2026. El Nino 2026-27 influence on climate may have similarities to the last intense episode observed in 2015-16 due to the oceanic warming taking place across vast mid-latitude regions not apparent during previous historic El Nino episodes observed in 1982-83 and 1997-98.