Highlight: Subsurface equatorial East Pacific support for La Nina is weakening. The La Nina in 2020 forecast is in jeopardy.
Discussion: During June and into early July subsurface equatorial cool water in the East Pacific has diminished (Fig. 1-2). The cool water source to fuel La Nina is weakening. Consequently, the trend of the Nino SSTA regions toward La Nina during late spring have eased off since mid-to-late June (Fig. 3). The La Nina episode forecast for later this year is in jeopardy. The full Climate Impact Company ENSO Outlook for 2020-21 will be issued later today.
Fig. 1: Subsurface upper ocean heat across the equatorial Pacific cooled rapidly during mid-to-late spring signaling La Nina ahead! However, the cool subsurface weakened in June.
Fig. 2: Subsurface upper oceanic cooling east of the Dateline was impressive and signaled La Nina ahead in May. However, the subsurface cooling has diminished in recent weeks.
Fig. 3: The 12-week Nino SSTA monitor indicates the cooling toward La Nina in late spring has eased. Neutral ENSO is present now!