The preliminary outlook indicates MAY-SEP 2021 is hotter than last year as the average of the U.S. cities CDD forecast is about 112% of the 30-year normal compared to just-under 109% last year. Meteorological summer (JUN/JUL/AUG) is not quite as hot as last year.

Last week southern oscillation index returned to weak positive phase and trade winds off the northwest coast of South America also returned. As a result, the increased trade winds up-welled cool waters to cause all Nino SSTA regions to fall to within La Nina thresholds. However, the subsurface at 75+ meters continue to warm and subsurface cool water supply to sustain La Nina is steadily losing amplitude.