Tropical
Highlights - April 2021
During April
2021, sea surface
temperatures (SSTs) were near-average in the central equatorial Pacific and below-average across the eastern equatorial Pacific (Fig. T18).
The latest monthly
Niņo indices were -0.8°C for the Niņo 1+2
region, -0.5°C
for the Niņo 3.4 region and -0.2°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 above-average
across much of the equatorial Pacific (Figs. T15,
T16). The
corresponding sub-surface temperatures were 1-3°C above-average (Fig. T17).
Also during April, the lower-level easterly
winds and the upper-level westerly winds were above-average across the
east-central and eastern equatorial Pacific (Fig. T20, Fig. T21).
Meanwhile, tropical convection was near-average over the central equatorial
Pacific and suppressed over Indonesia (Figs.
T25, E3).
Collectively, these oceanic and atmospheric anomalies reflected a transition
towards 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
