Tropical Highlights – October 2012

 

 

 During October 2012, the sea surface temperatures (SSTs) remained slightly warmer-than-average across the central and east-central equatorial Pacific, but colder-than-average over the far eastern equatorial Pacific (Fig. T18, Table T2). The latest monthly Niño indices were +0.3°C for the Niño 3.4 region and -0.1°C for the Niño 1+2 region (Table T2, Fig. T5). Consistent with these conditions, the depth of the oceanic thermocline (measured by the depth of the 20°C isotherm) remained slightly above-average across the central and east-central equatorial Pacific (Figs. T15, T16).

The Southern Oscillation Index (SOI) remained near average during October, with the latest monthly index value being +0.3 (Table T1). Meanwhile, the equatorial low-level easterly trade winds remained slightly enhanced over the west-central equatorial Pacific and slightly weaker than average across the east-central equatorial Pacific (Table T1, Fig. T20). This pattern is largely consistent with continued ENSO-neutral conditions.  Enhanced convection, although weak, was seen over the western equatorial Pacific and near the Date Line (Figs. T25, E3), which is consistent with weak El Niño conditions. Collectively, these oceanic and atmospheric anomalies reflect borderline ENSO-neutral/ 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