June 2018 Climate Forecast Discussion
June 2018 Climate Forecast Discussion for Jul-Sep through Oct-Dec
The SST forecast shows weak El Nino conditions developing for the initial Jul-Sep season, slowly intensifying to moderate strength (>1.0C in the Nino3.4 region) by Oct-Dec. Much of the subtropical and extratropical North Atlantic, and the North Pacific SST, as well as the SST in much of the mid-latitude Southern Hemisphere, are predicted to be above average during all four forecast seasons. An exception is noted in the high latitude southeast Pacific waters in the Southern Hemisphere and the high latitude waters around North America, which are predicted to be below average during all four forecast seasons. A very slightly positive Indian Ocean Dipole in Jul-Sep is predicted to strengthen to become moderately strongly positive by Oct-Dec. Near-average SST is predicted for the tropical Atlantic for Jul-Sep through Oct-Dec.
Strongly enhanced probabilities for below-normal precipitation are predicted for Central America and the Caribbean islands for Jul-Sep through Sep-Nov, Indonesia for July-Sep through Oct-Dec, and for part of northern South America for Aug-Oct through Oct-Dec. A tilt of the odds toward below-normal is also predicted for varying parts of Australia for Jul-Sep through Oct-Dec, and central Africa for Oct-Dec. Enhanced chances for above-normal precipitation are forecast for parts of the African Sahel and Gulf of Guinea for Jul-Sep and Aug-Oct, for eastern equatorial Africa for Aug-Oct through Oct-Dec, for the southern U.S. and/or Mexico for Sep-Nov and Oct-Dec, and for central-southwest Asia and part of northern Asia for Sep-Nov and Oct-Dec.
Enhanced probabilities for above-normal temperature are predicted for Greenland, and for varying parts of Asia, Europe, northern Africa, North America and South America from Jul-Sep through Oct-Dec. A tilt of the odds toward above-normal is also predicted for parts of Australia from Aug-Oct through Oct-Dec, most strongly for the last two periods. Enhanced probabilities for below-normal temperature are relatively scant, but do appear in part of northern North America and part of northern Asia in Sep-Nov and Oct-Dec. An enhanced likelihood for near-normal temperature is predicted for small parts of northeastern South America and central and northwestern Africa mainly for Jun-Aug and Jul-Sep.
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