El Niño Update [28 Oct 2009]

ENSO Cycle: Recent Evolution, Current Status and Predictions

The following UPDATE is prepared by

Climate Prediction Center / NCEP –  26  October 2009

The latest weekly SST departures are:

• Niño 4   ~  1.4ºC
• Niño 3.4  ~  1.1ºC
• Niño 3 ~ 0.8ºC
• Niño 1+2 ~ 0.1ºC

El Niño Map. [SOURCE: NOAA/ Climate Prediction Center / NCEP]

SST Departures (°C) in the Tropical Pacific During the Last 4 Weeks
During the last 4-weeks, equatorial SSTs were at least 1.0°C above average between 165°E and 140°W and in small areas in the eastern Pacific.

Global SST Departures (°C)
During the last four weeks, equatorial SSTs were above-average in the Pacific and Indian Oceans. Also, above-average SSTs covered large areas of the Northern Hemisphere subtropics.

Weekly SST Departures (°C) for the Last Four Weeks

• During the last four weeks, equatorial SST anomalies strengthened across the central Pacific Ocean.

• During the last 30 days, equatorial SST anomalies increased over the central Pacific.

Tropical OLR and Wind Anomalies During the Last 30 Days

• Positive OLR anomalies (suppressed convection and precipitation, red shading) were present over Indonesia, Malaysia, and Australia. Negative OLR anomalies (enhanced convection and precipitation, blue shading) were located across the Philippines, Papua New Guinea, and in the western tropical Pacific Ocean.
• Low-level (850-hPa) equatorial winds were near-average over the central and eastern Pacific. Westerly anomalies were observed in the western Pacific.
• Upper-level (200-hPa) easterly anomalies were observed across most of the equatorial Pacific.

Pacific Niño 3.4 SST Outlook

• Most ENSO models indicate El Niño will continue through the Northern Hemisphere winter 2009-10.

• The models disagree on the eventual strength of El Niño (SST anomalies ranging from +0.5°C to greater than +2.0°C), but a majority indicate at least a moderate strength El Niño (greater than +1.0°C) during during November-December-January 2009-10. Figure provided by the International Research Institute (IRI) for Climate and Society (updated 15 Oct 2009).

SST Outlook: NCEP CFS Forecast Issued 18 October 2009
The CFS ensemble mean predicts El Niño will last through Northern Hemisphere winter 2009-10.

Summary

• El Niño is present across the equatorial Pacific Ocean.
• Sea surface temperatures (SST) were at least 1.0ºC above-average across much of the central and east-central equatorial Pacific.
• Based on current observations and dynamical model forecasts, El Niño is expected to strengthen and last through Northern Hemisphere winter 2009-10.

Information and images on this page are sourced from Climate Prediction Center/NCEP/NOAA.

Related Links:

• Recognizing El Niño
• El Niño and La Niña: Tracing the Dance of Ocean and Atmosphere
• TAO Diagrams
• El Niño Forecasts

El Niño Updates:

• El Niño [Main Page and Archive]