August 2020 Climate Forecast Discussion for Sep-Nov through Dec-Feb
The SST forecast indicates weak-moderate La Niña conditions in the east-central tropical Pacific Ocean for all four forecast periods of Sep-Nov through Dec-Feb, with a slight weakening in Dec-Feb. Through the forecast periods, the eastern three-quarters of the tropical Pacific shows negative anomalies while the far west Pacific shows positive anomalies with the contrast becoming weaker following Oct-Dec. A tendency for a weak negative Indian Ocean dipole is predicted for the first two seasons, with weak Indian Ocean SST anomalies predicted thereafter. Much of the extratropical Atlantic and North Pacific SSTs are predicted to be above average during the four forecast seasons
An enhanced probability for below-normal precipitation is forecast in parts of Chile and Argentina, eastern Africa, central SW Asia for Sep-Nov and Oct-Dec. Dryer than normal tendencies extend to parts of the southern U.S., northern Mexico, southern China and far eastern Asia in Oct-Dec and Nov-Jan; these weaken over South America after Oct-Dec, but strengthen over parts of the southern U.S., northern Mexico into Dec-Feb.
Enhanced chances for above-normal precipitation are predicted most prominently over the Maritime Continent and over much of Australia for Sep-Nov and Oct-Dec, weakening thereafter. Tendencies toward above-normal precipitation are predicted in Nov-Jan and Dec-Feb over northern South America and southern Africa, as well as parts of central and West Africa, though these tendencies are generally weak.
The above precipitation tendencies in these regions are consistent with the predicted weak-moderate La Nina conditions.
Enhanced probabilities for above-normal temperature are predicted for North America, Greenland, and varying parts of Asia, Africa, North America, South America and Europe through the forecast seasons.
