Skip Navigation Links 
NOAA logo - Click to go to the NOAA home page National Weather Service   NWS logo - Click to go to the NWS home page
Climate Prediction Center

Expert Assessments
   ENSO Diagnostic
     Discussion Archive

About Us
   Our Mission
   Who We Are

Contact Us
   CPC Information
   CPC Web Team

HOME > Expert Assessments > ENSO Diagnostic Discussion
issued by
8 July 2010

ENSO Alert System Status: La Niña Watch


Spanish Version


Synopsis: La Niña conditions are likely to develop during July - August 2010.

During June 2010, sea surface temperature (SST) anomalies continued to decrease across the equatorial Pacific Ocean, with negative anomalies expanding across the central and eastern Pacific (Fig. 1). While the rate of decrease slowed during June, all of the Niño indices were cooler compared to the previous month (Fig. 2). The subsurface heat content (average temperatures in the upper 300m of the ocean, Fig. 3) also remained below-average during the month. Subsurface temperature anomalies became increasingly negative in the east-central equatorial Pacific and extended to the surface across the eastern half of the basin (Fig. 4). Also during June, enhanced convection persisted over Indonesia, while the area of suppressed convection strengthened and expanded westward over the western and central equatorial Pacific (Fig. 5). Enhanced low-level easterly trade winds and anomalous upper-level westerly winds prevailed over the western and central equatorial Pacific. Collectively, these oceanic and atmospheric anomalies reflect developing La Niña conditions. .

The majority of models now predict La Niña conditions (SST anomalies less than or equal to -0.5oC in the Niño-3.4 region) to develop during June-August and to continue through early 2011 (Fig. 6). Confidence in this outcome is reinforced by the recent performance of the NCEP Climate Forecast System (CFS) (Fig. 7), the large reservoir of colder-than-average subsurface water (Fig. 3), and signs of coupling with the atmospheric circulation. Therefore, La Niña conditions are likely to develop during July-August 2010.

This discussion is a consolidated effort of the National Oceanic and Atmospheric Administration (NOAA), NOAA's National Weather Service, and their funded institutions. Oceanic and atmospheric conditions are updated weekly on the Climate Prediction Center web site (El Niño/La Niña Current Conditions and Expert Discussions). Forecasts for the evolution of El Niño/La Niña are updated monthly in the Forecast Forum section of CPC's Climate Diagnostics Bulletin. The next ENSO Diagnostics Discussion is scheduled for 8 July 2010. To receive an e-mail notification when the monthly ENSO Diagnostic Discussions are released, please send an e-mail message to:

Climate Prediction Center
National Centers for Environmental Prediction
NOAA/National Weather Service
Camp Springs, MD 20746-4304

NOAA/ National Weather Service
National Centers for Environmental Prediction
Climate Prediction Center
5200 Auth Road
Camp Springs, Maryland 20746
Page Author: Climate Prediction Center Internet Team
Page last modified: June 3, 2010
Information Quality
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities