SHEAR LUCK
Forecasters think El Niño will be strong from mid-August through October.
El Niño is ramping up, and that’s good news for South Florida.
Renowned for ripping apart storms, the large-scale weather pattern significantly reduces the chance of a hurricane striking this region.
“About one in five seasons with El Niño have hurricane strikes in South Florida,” compared to once every three to four years without it, said meteorologist Robert Molleda, of the National Weather Service in Miami.
The National Oceanic and Atmospheric Administration first announced El Niño had A traffic light dangles after Hurricane Jeanne passed through West Palm Beach in 2004. emerged in March but said the weather pattern probably would be weak.
Now forecasters think it will be strong from mid-August through October, when about 80 percent of a season’s tropical activity usually occurs.
Some atmospheric models predict this El Niño will be “one of the strongest on record, back to 1950,” said Phil Klotzbach, the Colorado State University climatologist who develops seasonal predictions.
El Niño is created out of abnormally warm waters in the equatorial eastern Pacific
Ocean. That heat nurtures thunderstorm activity, which, in turn, triggers strong wind shear in the atmosphere above the Atlantic basin.
That shear frequently weakens storms or stops them from forming altogether.
However, sometimes other atmospheric factors override El Niño’s impact, such as extremely warm water in the Atlantic or a temporary weakening of the wind shear. Those factors were at play in 2004, an El Niño year that saw four hurricanes — Charley, Frances, Ivan and Jeanne — slam the state.
Still, El Niño is a good friend to Florida. The state has a 50 percent chance of being struck by a hurricane in any given year. When El Niño is active, those odds drop to 33 percent, Klotzbach said. Overall, the weather pattern results in an average of three fewer named storms and two fewer hurricanes per season. The typical season sees 12 named storms, including six hurricanes.
While El Niño slows down the Atlantic hurricane season, it usually energizes the eastern Pacific storm season with warm water, sometimes up to 10 degrees above normal.
Why that ocean heats up without any real pattern isn’t fully understood. But scientists think the tropical Pacific receives more sunlight than any other region on Earth, and that warms the sea surface.
Because of El Niño, Klotzbach and colleague William Gray are holding to their prediction for a total of eight named storms this year.
That would translate to only six more storms until the season officially ends on Nov. 30. Tropical storms Ana and Bill already have emerged.
“We’re sticking to our guns,” Klotzbach said. “It’s fairly typical to get early season storms in El Niño years.”
Be ready
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