06/19/2018 07:00AM ● Published by Robert Frey
Forecasting The 2018 Hurricane Season In AcadianaBy Wynce Nolley
Summer 2018 marks the beginning of yet another hurricane season in Acadiana and across the Gulf Coast, and with the region’s recent history of calamitous weather events, it is increasingly important to be as prepared and informed about the upcoming hurricane season in case of another serious natural disaster.
“Generally the hurricane season starts June 1 and ends Nov. 30,” says KATC Chief Meteorologist Rob Perillo. “Prime time for Acadiana for most of the storms usually is the third or fourth week of August through the first week of October. That’s the time that we’re most likely going to be affected by the tropics.”
Though it’s relatively early, Perillo says he has an idea of how this season is shaping up and what Acadiana and the Gulf Coast may expect in terms of hurricanes and/or major flooding events.
“So, this year the forecast is for slightly above normal activity, but that could change depending on how upper level winds prevail moving forward as we get closer to June and into July,” says Perillo.
Perillo says that the big question right now is whether there is going to be an El Niño or La Niña pattern or a neutral pattern, which describes water temperature in the Equatorial Pacific. Right now, he says that each is at a 33 percent chance of happening.
“If there’s an El Niño, that usually allows for stronger wind shear and kind of knocks down on storms and storm intensity,” he says. “But, La Niña, like what we had last summer, actually enhances the tropical activity and that’s what we saw last year especially across the Caribbean where storms got going and were quite intense for several days.”
However, Perillo says that neither may make much of a difference in terms of storms along the Gulf of Mexico.
“Whether it’s a busy season or whether it’s an El Niño season and it’s not busy, it doesn’t make that much difference on the Gulf Coast,” he says. “There are still fairly equal chances of having a big storm in the Gulf whether it’s a busy season or not.”
And according to noted forecaster Dr. Philip Klotzbach and Dr. Michael Bell of Colorado State University’s Department of Atmospheric Science, they anticipate that the 2018 Atlantic Basin hurricane season will have slightly above average activity.
As forecasted in their annual Atlantic Seasonal Hurricane Activity and Landfall Strike Probability, the current weak La Niña event appears likely to transition to neutral El Niño-Southern Oscillation (ENSO) over the next several months. However, they currently do not anticipate a significant El Niño event this summer/fall.
Their forecast also states that the western tropical Atlantic is anomalously warm right now, while portions of the eastern tropical Atlantic and far North Atlantic are anomalously cool. As such, they anticipate a slightly above-average probability for major hurricanes making landfall along the continental United States coastline and in the Caribbean.
The Atlantic Basin Seasonal Hurricane Forecast for 2018 also reports 7 hurricanes, 14 named storms, 70 named storm days, 30 hurricane days, 3 major hurricanes and 7 major hurricane days.
“We have a pretty good idea of how many storms are going to be supported by the Atlantic Basin, but we have little to no skill in forecasting where the storms are going to go,” says Perillo. “So that’s why we say whether the forecast is going to be a busy season or not, every year you have to be equally prepared for the possibility for a tropical storm or hurricane.”
According to Perillo, the long term statistics for Acadiana are that the region averages a hurricane coming very close to the area or impacting the area once every 5 years; a tropical storm once every 2 years; and a tropical depression once a year.
“We run the gamut in between,” he adds. “Like in 2016, we didn’t even have a tropical system, or even a named system, yet we had the tropical floods that flooded more than 150,000 homes in August of 2016. So, the hurricanes are the big sexy things we talk about, but the lesser storms that may be slow moving or stalled, they can be equally as devastating.”
These slow moving storms proved just as devastating to the region as any hurricane. And when those 100-year floods drowned much of Acadiana, they caught most of its residents off guard and ill-prepared to face the crippling aftermath.
“A lot of people talk about climate change and impacts on the hurricanes and there’s really not much we can talk about that is verifiable at this point,” says Perillo. “However, a warmer atmosphere, which we have observed, and a warmer Atlantic Basin, which we have observed, and a warmer Gulf of Mexico all translate to higher moisture content available in the atmosphere. So more frequent and heavier tropical rainfall events are certainly likely and have been observed and will continue.
Perillo says that this warming trend could lead to more frequent flooding in the region in the near future.
“We’re kind of in the middle of this new paradigm where even your typical slow moving tropical thunderstorm in the summer has more potential to flood than it did say 30 years ago,” he adds. “So, my main concern continues to be yeah, the hurricanes absolutely, but these slow moving tropical systems have greater propensity to flood. And at the same time, we can see it build and build, so there’s always that man-made impact where we continue to develop land areas and don’t allow for the proper drainage when we have this 10” rainfalls in three hours.”
Acadiana residents and those that live along the coast are used to the usual preparedness options for each hurricane season like stocking up on supplies well ahead of time, having an evacuation plan and weather-proofing their homes. However, they must now consider preparing for another major flood event on top of the possibility of a major hurricane each season.
Perillo says one option that may not sound ideal is to look at getting flood insurance.
“Well, no matter whether you think you’re in a flood zone or not, I think flood insurance is a necessary evil,” he says. “But it’s cheap if you’re not in a flood zone, and it pays back in spades when you do have a disaster.
“And then the other thing that I’ve learned just from my house flooding back in 2016 is to have plenty of cash on hand, because before you can even get paid by the flood insurance people you have a lot of extra expenses,” says Perillo. “You may have to not live in your home, or pay extra rent on top of a mortgage and everything else.”
Residents can keep on top of the latest major weather events by staying tuned to Rob Perillo and the KATC Weather Team at www.KATC.com or by getting the KATC Weather App. There is also additional hurricane/weather information available at the Governor’s Office of Homeland Security and Emergency Preparedness website, www.GetAGamePlan.org, and from the National Hurricane Center through its website at www.NHC.NOAA.gov.