We received a great viewer question in our email box this morning, one that I'm sure many of you are wondering the answer to. Sandy writes:
I was wondering if this El Nino which is present now will be in place during the hurricane season. If so, does it mean we might have a mild hurricance season - at least, I am hoping!
One of the major weather patterns we've been following this winter is El Nino. As many of you know, this is a pool of warmer than average sea surface temperatures that extends along the equator in the Pacific Ocean. While we're most concerned with water temps in the eastern Pacific, also included in the El Nino "index" is the water temperature in the central and western equatorial Pacific. Below I've included a loop of sea surface temperatures (SSTs) across the Pacific Ocean.. the second image is SST anomalies (or the departure from normal water temps).
You can obtain both of these images, and other El Nino data, from the Climate Prediction Center. The second image really tells the story. Notice how the bright orange and red colors are disappearing in the equatorial Pacific between about 90W and 180W. What this means is that water temperatures are returning much closer to averages. In fact, the water temperatures in the eastern Pacific, once running at least 1-3 degrees Celsius above average (as recently as late November) are now close to average. Thus, we are trending toward a weakening El Nino at this point.. and that correlates with a weaker jet stream over the Atlantic basin (potentially) during the upcoming hurricane season.. thus less wind shear. All else being equal, this could add up to a more active season in 2010!
We'll be monitoring El Nino and other factors as we continue to look into the 2010 Atlantic hurricane season. But at this point, we are trending toward a weakening warm phase of what's known as the El Nino Southern Oscillation (ENSO)!
Brian
