La Nina Update Mid-August

While our Summer months have been the hottest on record so far in Richmond and central Virginia, the Equatorial Pacific has been cooling significantly into La Nina conditions (above: blue shades indicate ocean cooling along the equator. For your reference, here's a broader view below).

You can see the deviation below the long-term average ocean surface temperature in this chart below where there is blue coloring:

The different Nino levels (1+2, 3, etc.) are simply different indicators used to determine the strength of the La Nina/El Nino event. Our dip out of El Nino toward La Nina began in late February, reaching negative anomolies by late April. La Niña conditions are likely to continue through early 2011, according to the Climate Prediction Center forecast data:

(Outlook figure provided by the International Research Institute for Climate and Society, updated 16 July 2010.)

What does this mean for Virginia through October? We should keep running warmer than average into the Fall. As for rainfall, we can go either way in a La Nina setup in the Fall with being wetter or drier than normal. Let's hope we are wetter than average so we get out of this drought!