During September, ENSO-neutral conditions were reflected in near-to-below average sea surface temperatures (SSTs) across most of the central and eastern Pacific Ocean.
Over the western equatorial Pacific Ocean, low-level trade winds were anomalously easterly and upper-level winds were anomalously westerly. Overall, the ocean and atmosphere system remains consistent with ENSO-neutral, although edging closer to La Niña conditions.
La Niña conditions are favored (~55-65%) during the Northern Hemisphere fall and winter 2017-18.
