El Niño, La Niña jolt Florida throughout year in many different ways


Viera Voice Graphic

The Pacific Ocean is a long way from Florida, but it’s role in affecting Florida’s weather can’t be downplayed.

The warming or cooling of water temperatures in the eastern equatorial Pacific Ocean impacts weather in Viera and Suntree quite a bit.

A big factor in whether or not the Atlantic hurricane season has a lot of activity is the difference in water temperatures thousands of miles away. The unusual warmth of those waters is called El Niño, while the phenomenon that produces cooler than normal water temperatures is referred to as La Niña. Combined, they are part of what is called the El Nino Southern Oscillation (ENSO) cycle.

Traditionally, El Niño seasons lead to less activity during the Atlantic hurricane season. La Niña years can lead to increased activity in the basin. This is due to the fact that El Niño causes increased wind shear in the basin, which helps to inhibit tropical cyclone development.

As for this year’s forecast?

“We called for a total of 13 named storms. Of those 13, five (will) become hurricanes. And, of those five, two (will) become major Category 3, 4, 5 hurricanes (with) winds of 111 mph or greater,” said Phil Klotzbach, the lead forecaster with Colorado State University’s Tropical Meteorology Project.

The Tropical Meteorology Project produces one of the most renowned seasonal forecasts for the Atlantic basin each year at the Governor’s Hurricane Conference in West Palm Beach in May.

“An average season has about six hurricanes and three major hurricanes,’’ Klotzbach said. “So, it’s a little bit below average, but not massively below.”

Klotzbach said, “there’s two big factors that went into that. The first big one is El Niño, which is warmer than normal water in the eastern and tropical Pacific. Right now, we have what is known as a weak El Niño. So, it’s El Niño, but it’s not particularly strong. What you basically have is El Niño conditions tend to increase upper-level winds that tear apart hurricanes. The million dollar question that we asked in April and we’re still asking now is ‘is that El Niño going to persist?’ And, if you look at the models, there’s a lot of spread.”

There’s a fair bit of uncertainty with this seasonal forecast, according to Klotzbach.

“I don’t think we really know what ENSO’s going to do,’’ Klotzbach said. “The majority say maybe more El Niño-like, but there’s a lot of uncertainty. Obviously, if the atmosphere gets more El Niño-like, it would mean fewer Atlantic hurricanes because it increases the shear.”

Still, it only takes one storm to make a season. Ken Graham, the National Hurricane Center director, notes this was the case with one storm that was the first of the season in late August. That was unusual.

“Back in 1992, (it) was an El Niño year where you hardly had any hurricanes,’’ Graham said. “We got Hurricane Andrew, so I turn to history to think about the messaging.’’

Additionally, El Niño isn’t all good news for Central Florida. Tornado outbreaks during the winter have come during El Niño years.