Discussion: Strong subsurface warming in the equatorial East Pacific during the past several months is fading ending El Nino onset risk over the next couple months. A new Kelvin Wave moving east of the Dateline in August must reach the northwest coast of South America during northern hemisphere autumn to ignite El Nino onset, probably not until NOV/DEC 2018. El Nino is still possible but delayed.
The Nino SSTA regions have cooled east-central/east equatorial Pacific in recent weeks (Fig. 1). Warmest NINO SSTA region clearly is near the Dateline indicating a weak El Nino Modoki signature right now (Fig. 2).
Fig. 1: Nino SSTA regions during the past 12 weeks indicate the east-central/east Pacific (N34, N3 and N12) have cooled recently.
Fig. 2: The difference between Nino3 and Nino4 SSTA zones identifies an El Nino Modoki index. The trend is toward El Nino Modoki in August.