Forecasters Predict Less-Active Hurricane Season

Cooler ocean temperatures and the atmosphere stability are producing a less active Atlantic hurricane season than initially predicted in May.

Seasonal forecasters with the National Ocean and Atmospheric Administration’s Climate Prediction Center have increased the likelihood of a below-normal Atlantic hurricane season to 60 percent (up from 25 percent in May) in the updated outlook, issued August 10. The chance of a near-normal season is now at 30 percent, and the probability of an above-normal season has dropped from 35 percent to 10 percent.
For the full season that ends Nov. 30, NOAA predicts a total of up to 13 named storms (winds of 39 mph or greater). As many as seven will become hurricanes with winds of 74 mph or greater and up to two could become major hurricanes with winds of 111 mph or greater.

So far, the season has seen four named storms, including two hurricanes. An average six-month hurricane season produces 12 named storms, of which six become hurricanes, including three major hurricanes.

To produce the seasonal update, forecasters take several factors into account. El Nino is expected to develop with enough strength to suppress storm development during the latter part of the season. On August 10, NOAA’s Climate Prediction Center updated its forecast to a nearly 70 percent likelihood of El Nino during the hurricane season.

Sea-surface temperatures across the tropical Atlantic Ocean and Caribbean Sea have remained cooler than average. A combination of stronger wind shear, drier air and increased stability of the atmosphere in the region where storms typically develop will further suppress hurricanes. Storm activity to-date and the most recent model predictions also contribute to this update.

NOAA also urges coastal residents to make sure they have their hurricane preparedness plans in place and to monitor the latest forecasts as we move into peak hurricane season.