Tropical
Highlights - December 2019
During December
2019, sea surface
temperatures (SSTs) were above-average across
the western and central equatorial Pacific and near-average in the eastern
equatorial Pacific (Fig. T18, Table T2).
The latest monthly
Niņo indices were +0.3°C for the Niņo 1+2
region, +0.5°C
for the Niņo 3.4 region and +1.0°C for the Niņo 4 region (Table T2,
Fig. T5). The depth
of the oceanic thermocline (measured by the depth of the 20°C isotherm) was above-average
across the central and eastern equatorial Pacific (Figs. T15, T16). The corresponding sub-surface
temperatures were 1-3°C above average in the eastern equatorial Pacific (Fig. T17).
Also during December, the
lower-level easterly winds were weaker than average (indicated by westerly
anomalies) across the equatorial Pacific (Table
T1, Fig. T20). The
upper-level winds were near-average over much of the equatorial Pacific (Table T1, Fig. T21). Meanwhile,
tropical convection was enhanced to the west of the Date Line and suppressed over
Indonesia and the central equatorial Pacific, just east of the Date Line (Figs. T25, E3). Collectively, these oceanic and
atmospheric anomalies were consistent with ENSO-neutral 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
www.nws.noaa.gov
