Normal could still be bad.
On Friday, the National Oceanic and Atmospheric Administration forecast an average number of storms for the Atlantic hurricane season, with 10 to 16 named storms, four to eight hurricanes and one to four major storms packing winds over 110 mph. But that doesn’t mean that the season, which officially begins Wednesday, could be without trouble. Already a storm has bucked the odds by threatening to form off the coast of Florida over the holiday weekend.
“This is the season to be sure you’re ready for hurricanes and not banking on statistical odds,” NOAA Administrator Kathryn Sullivan said at the agency’s briefing in Maryland.
While they expect a 70 percent chance of the season playing out near normal, Sullivan said several factors make the prediction more uncertain. The El Niño that helped keep the 2015 season slow has begun to fizzle, but it’s not clear if it will actually end before the season begins. Forecasters believe a La Niña, which can fuel storms, has a good chance of forming during peak storm months in August and September, so the back half of the season could be busier.
The outcome of a natural variation in Atlantic water temperatures that occurs over long periods of time, called the multi-decadal oscillation, is also uncertain, Sullivan said. Forecasters believe the oscillation may be transitioning to cooler temperatures, which would tamp down storms. But it’s not yet clear.
“We’re now seeing a cold AMO in the winter and the spring, but not in summer,” said lead forecaster Gerry Bell. “It may take a few years before we know.”
Armed with a suite of new tools, including a powerful new satellite, Sullivan said NOAA forecasters will be better able to forecast storms and issue warnings, including storm surge and flooding that cause the most storm-related deaths.
Among the advances:
▪ A new GOES-R weather satellite set to launch later this year will provide images of the earth every 30 seconds, scanning the planet five times faster than current satellites to provide more robust data for storm models.
▪ Improved super-computing ability that has helped hurricane forecasters improve predictions by 20 percent in the last five years.
▪ Improvements to the hurricane center’s storm model that provides hourly forecasts with tracks now provided five days out.
▪ Storm surge maps that will be issued with storm warnings and will provide forecasts for likely surges along the coast, allowing emergency managers to make better decisions about evacuations.
▪ Improved inland flooding forecasts.
But even with all the additional tools, Sullivan said their best weapon remains public preparation.
“It only takes one storm, however intense the season is, to be really devastating to homes and communities,” she said. “Andrew was a very low year. It was about the only storm that formed. But it also absolutely devastated a very wide swath of South Florida.”
Follow Jenny Staletovich on Twitter @jenstaletovich