May 2019 Climate Forecast Discussion for Jun-Aug through Sep-Nov
The SST forecast shows weak El Nino conditions (0.5 - 1.0ºC for the Nino3.4 SST index) for Jun-Aug through Sep-Nov, very slowly weakening during the forecast period. Much of the extratropical North Atlantic and North Pacific SSTs, as well as the SSTs in the western Indian Ocean and parts of the middle and high latitude south Pacific, are predicted to be above-average during most of the four forecast seasons. A small area of below-average SST is predicted in the very high latitudes south or southwest of South America and south of Australia for all four forecast seasons. A positive Indian Ocean Dipole is predicted for all four forecast seasons, and near-average SST is predicted for the north and south tropical Atlantic for all four forecast seasons.
An enhanced probability for below-normal precipitation is forecast for all four forecast seasons (Jun-Aug through Sep-Nov) for much of Indonesia, and eastern and extreme southwestern Australia. A tilt of the odds toward below-normal is also predicted for Central America and the Caribbean for Jun-Aug and Jul-Sep (and more weakly for Aug-Oct and Sep-Nov), part of northern South America for Jul-Sep through Sep-Nov, northern Australia for Aug-Sep and Sep-Nov, and the Philippines for Sep-Nov. Weakly enhanced chances for above-normal precipitation are forecast for parts of eastern equatorial Africa for all four forecast seasons, parts of southeastern South America for Jun-Aug, Jul-Sep and Sep-Nov, and part of interior western equatorial South America for Jun-Aug and Jul-Sep. A preference for above-normal is also forecast for central southwest Asia for Jun-Aug, part of northern Asia for Sep-Nov, and part of the western U.S. for all four forecast seasons.
Enhanced probabilities for above-normal temperature are predicted for Greenland, and varying parts of Australia, Asia, Africa, North America, South America and Europe from Jun-Aug through Sep-Nov. Tilts of the odds are strongest for all four forecast seasons in Greenland and in varying portions of central or northern Asia. Strongly enhanced probabilities for above-normal are also forecast for eastern Europe for Jul-Aug and Aug-Oct and far northern North America for Sep-Nov. For most of the forecast seasons, the above-normal signal is weak or absent in central Africa and the southern quarter of South America. Enhanced probabilities for below-normal temperature do not appear in this set of forecasts. An enhanced likelihood for near-normal temperature is predicted for parts of northern or northeastern coastal South America and central Africa for all four forecast seasons, and in part of northern Africa for Jun-Aug.
The next seasonal climate forecast will be available on Friday, June 14 2019
