It’s approaching mid-June and the latest info from the Climate Prediction Center and International Research Institute (CPC/IRI) suggests that El Nino is not going to happen this hurricane season.
First, what is El Nino and why is it an issue? Well, basically, it is the abnormal warming of the tropical Pacific along and near the Equator. This warming tends to throw off the typical weather pattens and usually equates to a below-average Atlantic hurricane season. This is due to stronger upper level winds, or shear, that streaks across the tropical Atlantic and Caribbean, cutting off the tops of developing hurricanes. In the absence of El Nino, we often experience a busy Atlantic hurricane season, especially if the tropical Atlantic sea surface temps are themselves running above average – as is the case this season.
For reasons not well understood, El Nino comes and goes every few years. In between we have neutral periods where the water temps are more or less average. Then we have La Nina or an abnormal cooling of the tropical Pacific. That phenomenon also has its own set of interesting side-effects which are better explained another time. For this season, we are looking at a neutral pattern setting up and remaining in place.
The latest data and forecast from the CPC/IRI suggests less than a 10% chance of seeing El Nino develop during the August/September/October peak time of the Atlantic hurricane season. This should act to allow for prolofic development once we reach mid-August and beyond, especially considering the warmer than average SSTs in the Atlantic.
This chart gets updated a couple of times per month and I’ll post another write up on the state of the ENSO or El Nino Southern Oscillation towards the end of the month. In the meantime, the tropics are nice and quiet with no areas of concern noted in either the east Pacific or the the Atlantic.