Characteristic of climate change is the evolution of marine heatwaves (MHW) as part of the warming of the global ocean surface in recent decades, particularly the last 10-15 years. Climate Impact Company follows MHW’s closely and their potential atmospheric impact. A recent MHW forming southwest of Africa is intensifying.

The NCEP CFS V2 Nino34 SSTA forecast has relentlessly been forecasting a flip from the current strong oceanic El Nino to similarly intense La Nina by the end of 2024. Given the strength of the current El Nino and the general oceanic anomalous warmth poleward of the Pacific tropics, a rapid shift toward strong La Nina seems unrealistic. The latest NCEP CFS V2 Nino34 SSTA forecast insists on a decline in El Nino with neutral ENSO by April, weak La Nina by June, and strong La Nina by October. A recent development supportive of this forecast is the sudden loss of upper ocean heat across the equatorial Pacific Ocean.

Entering 2024, drought concern in the southern hemisphere was present across Brazil, South Africa, and much of Australia. Interestingly, the drought focus as mid-summer approaches in Australia shifts to the western continent as heavy rains have affected parts of the East while the wet monsoon has emerged across the North. In South America, Argentina drought is nearly dissipated although short-term forecasts are hot and dry. Meanwhile, a dry start to summertime in Brazil reverses wetter in January.