I thought it would be worthwhile to share the current status on the developing La Niña. The La Niña is important because it is usually associated with decreased shear over the tropical Atlantic which correlates with more and stronger Atlantic basin hurricanes.
The above graphic is produced by NOAA’s Climate Prediction Center and shows the global sea surface temperature (SST) departures from normal over the period 27 June – 24 July, 2010. Note the blue (colder than normal SSTs) over the equatorial areas of the central and eastern Pacific signaling the development of La Niña.
The above graphic shows SST anomalies in the Niño 3.4 region forecast by various models and provided by the International Research Institute (IRI) for Climate and Society on July 16th. The majority of models indicate La Ninña conditions (Niño 3.4 SST anomalies 0.5 C or less) during the northern hemisphere summer 2010. IRI is saying there is a near 80% probability of La Ninña conditions not only during the July-September period but also through 2010.
Next week Klotzbach/Gray and NOAA will update their seasonal hurricane outlooks. Given the developing La Niña conditions along with the warmer than normal SSTs over the tropical Atlantic, I doubt that we will see any significant changes to their previous forecasts that called for a very active Atlantic hurricane season.