Tropical Highlights

  Table of Atmospheric Indices  (Table 1)

  Table of Oceanic Indices  (Table 2)

  Time Series

  Time-Longitude Sections

  Mean & Anomaly Fields

  Appendix 1: Outside Contributions

Tropical Highlights

MAY 2010

Positive sea surface temperature (SST) anomalies continued to decrease across most of the equatorial Pacific Ocean during May 2010 (Fig. T18).  The latest monthly SST indices were 0.0°C for both the Niño-3.4 and the Niño-3 regions. (Table T2, Fig. T5). Consistent with this evolution, the oceanic thermocline (measured by the depth of the 20°C isotherm) was shallower than average across the central and eastern equatorial Pacific (Figs. T15, T16), with sub-surface temperatures reaching 1°C to 3°C below average in the region (Fig. T17).

Also during May, equatorial low-level easterly winds remained stronger than average over the western and central Pacific, while the upper-level westerly wind anomalies persisted across the central and eastern Pacific (Table T1, Figs. T20 and T21). This wind pattern was associated with enhanced convection over Indonesia and suppressed convection across the central equatorial Pacific (Figs. T25, T26 and E3). Collectively, these oceanic and atmospheric anomalies reflect the demise of El Niño.

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