Tropical
Highlights - September 2020
During September
2020, sea surface
temperatures (SSTs) remained below-average across the
central and eastern equatorial Pacific (Fig.
T18). The latest monthly Niņo indices were -0.9°C for
the Niņo 1+2 region, -1.0°C for the Niņo 3.4 region and -0.4°C for the Niņo 4 region (Fig. T5, Table T2). The depth of
the oceanic thermocline (measured by the depth of the 20°C isotherm) was below-average
across much of the central and eastern equatorial Pacific (Figs. T15, T16). The corresponding sub-surface
temperatures were 1-4°C below-average in the eastern equatorial Pacific (Fig. T17).
Also during September, the
lower-level easterly winds were above-average across much of the equatorial
Pacific and the upper-level westerly winds were above-average over the eastern
equatorial Pacific (Fig. T20, Fig. T21). Meanwhile,
tropical convection was suppressed across the western and central equatorial
Pacific, and was slightly above-average over Indonesia (Figs. T25, E3). Collectively, these oceanic and
atmospheric anomalies were consistent with La Niņa conditions.
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