Busy Hurricane Season Expected
Like we need something else to worry about right now. But here you go: There’s a 60% chance this year of an above-average number of hurricanes in the Atlantic Basin, which includes the Caribbean and the Gulf of Mexico, NOAA announced today. That’s no guarantee it actually will be busy, nor that any of the storms will affect the United States, but the climate conditions are all in place for storms to develop and become strong.
The first named storm of the year already came and went. Arther became the first named tropical storm of the year earlier this month, with sustained winds exceeding 39 mph, but it did not become a hurricane. Arther ran northward off the Southeast U.S. coast before spinning out into the Atlantic this week and weakening. (The official start of hurricane season isn’t until June 1, but it’s not uncommon for storms to form earlier.)
The seasonal forecast also includes a 10% chance of a below-average storm count. But if all goes as expected, there will be 13 to 19 named storms, six to 10 of which will become hurricanes, and three to six that reach or exceed Category 3 status, with sustained winds of at least 111 mph. The forecast does not indicate how many might come ashore.
Here’s what’s driving the prediction:
El Nino conditions in the Pacific are expected to wane and possibly switch to La Nina. When El Nino is in place, warm water in the eastern Pacific — off the coast of the Americas — drives energy into the atmosphere that drifts across the content to the Atlantic, creating upper-level winds in the opposite direction of other prevailing winds. That creates shear, which can shave the tops of developing Atlantic storms, preventing hurricane formation or throttling the strength of those that form. If El Nino indeed fades, developing tropical storms in the Atlantic will find one less factor curbing their enthusiasm.
Meanwhile, water temperatures in the Atlantic and the Caribbean are above normal, NOAA said in a statement. Warm water is the fuel for any hurricane. In fact, a storm needs sea-surface temperatures to be at least 80° Fahrenheit (26.7° Celsius) for a hurricane to form and thrive.
“NOAA’s analysis of current and seasonal atmospheric conditions reveals a recipe for an active Atlantic hurricane season this year,” said Neil Jacobs, PhD, acting NOAA administrator.
The forecast is similar to one issued April 2 by Philip Klotzbach and colleagues at Colorado State University:
Named storms: 16
Major hurricanes: 4
“ We anticipate an above-average probability for major hurricanes making landfall along the continental United States coastline and in the Caribbean,” Klotzbach and his colleagues wrote upon issuing their annual prediction. “As is the case with all hurricane seasons, coastal residents are reminded that it only takes one hurricane making landfall to make it an active season for them. They should prepare the same for every season, regardless of how much activity is predicted.”