January 2020 Climate Forecast Discussion

January 2020 Climate Forecast Discussion for Feb-Apr Through May-Jul

The SST forecast shows mainly neutral ENSO conditions (-0.5 to 0.5ºC in the Nino3.4 SST index) for Feb-Apr through May-Jul, starting from near-El Nino levels for Feb-Apr and progressively cooling to weak La Nina conditions by May-Jul. Throughout the forecast periods, the eastern tropical Pacific is forecast to have a more negative anomaly than the central Pacific so that by May-Jul conditions become quite cold in the east. Most of the extratropical North Atlantic and North Pacific SSTs, as well as the SSTs in the western Indian Ocean and portions of the high latitude South Pacific, are predicted to be above-average during the four forecast seasons. Above-average SST is also predicted for much of the tropical Atlantic for the first two seasons. Relatively much smaller areas that are predicted to have below-average SST for most or all of the forecast seasons include the southeast or eastern tropical Pacific, southern extratropical Indian Ocean, and just south of Australia, A somewhat positive Indian Ocean Dipole is predicted for all four forecast seasons. This positive IOD is less pronounced than in observations during the last few seasons.

An enhanced probability for below-normal precipitation is forecast for Feb-Apr and Mar-May in parts of Indonesia, northern Australia, and for Feb-Apr in part of southeast Africa. Below-normal is also favored for Feb-Apr through Apr-Jun in the Philippines, for Feb-Apr in scattered portions of interior Asia, and for May-Jul in central Chile and coastal northeast Brazil. Enhanced chances for above-normal precipitation are predicted for Feb-Apr in coastal northeast Brazil, northeastern Scandinavia, and northeast Asia, and for Feb-Apr and Mar-May in far northern North America. A tilt of the odds toward above-normal is also forecast in eastern equatorial Africa for Feb-Apr, Mar-May and May-Jul.

Enhanced probabilities for above-normal temperature are predicted for Greenland, and varying parts of Australia, Asia, Africa, North America, South America and Europe from Feb-Apr through May-Jul. Tilts of the odds toward above-normal are strongest for Greenland for all four forecast seasons, and much of Asia in Mar-May. The tendency toward above-normal is generally weakest (or absent) in much of tropical Africa, India, much of Indonesia, the southern one-third of South America, and easternmost South America. An enhanced probability for below-normal temperature is predicted in just very scant locations, such as near Nepal for all four forecast seasons. Enhanced probabilities for near-normal temperature are forecast for all four forecast seasons in parts of northeastern South America, parts of equatorial Africa, Borneo and parts of Indonesia. Near-normal is also favored in southeast Asia for Apr-Jun and May-Jul.