Tropical
Highlights - September 2018
Sea surface
temperatures (SSTs) remained above-average across
the equatorial Pacific during September 2018 (Fig. T18, Table T2).
The latest monthly
Niņo indices were +0.5°C for the Niņo 4
region, and +0.3°C
for the Niņo 3.4 and Niņo 3 regions
(Table T2,
Fig. T5). The depth
of the oceanic thermocline (measured by the depth of the 20°C isotherm) was above-average
across the equatorial Pacific (Figs. T15, T16), and the
corresponding sub-surface temperatures were 1-3°C above average (Fig. T17).
Also during September, the lower-level
easterly winds were weaker-than-average (indicated by westerly anomalies) across
most of the equatorial Pacific (Table T1, Fig. T20), while the
upper-level winds anomalies were easterly over the central and east-central equatorial
Pacific (Fig. T21).
Meanwhile, convection was suppressed over Indonesia and the central equatorial
Pacific (Figs. T25,
E3). Collectively, these oceanic
and atmospheric anomalies reflect ENSO-neutral conditions with a tendency
towards a developing El Niņo.
For the latest status of the ENSO
cycle see the ENSO Diagnostic Discussion at:
http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/index.html
www.nws.noaa.gov
