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

SEPTEMBER 2009

Sea surface temperature (SST) anomalies remained above average across much of the equatorial Pacific Ocean during September 2009(Fig. T18).  Consequently, all of the Niño-region SST indices were about +0.8°C throughout the month, except for the Niño1+2 index, which dropped to +0.3°C during September (Table T2, Fig. T5). The oceanic thermocline along the equator, measured by the depth of the 20°C isotherm, remained deeper than average across the Pacific Ocean (Figs. T15, T16). Consistent with these conditions, temperatures were 1^o-2^oC above average at thermocline depth across the equatorial Pacific (Fig. T17).  

Also during September, convection was suppressed across Indonesia but enhanced over the west-central Pacific (Figs. T25, E3). In addition, westerly wind bursts were observed over the western equatorial Pacific during the month (Figs. T13, T20). This coupling of the oceanic and atmospheric anomalies indicates a continuation of weak El Niño 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