The Atlantic Hurricane Season went silent after Hurricane Elsa in early July, but that quiet period likely comes to an end soon.
NOAA’s latest Atlantic Hurricane Season Outlook (released on August 4th) outlines what could be a substantial ‘upswing’ in tropical cyclone development in the Atlantic basin through the rest of the season.
A record setting season so far…
Hurricane Elsa developed early for an ‘E’ storm: the earliest fifth storm on record.
The five storms thus far (Ana, Bill, Claudette, Danny and Elsa) already produced above-average ‘Accumulated Cyclone Energy’ in the Atlantic.
As of this writing on August 4th, the global ‘drivers’ are lining up in such a way to expect a sharp increase in tropical storm or hurricane development over the next 4-6 weeks: right in line with ‘normal’ expectations around the peak of hurricane season.
What does this mean for Alabama and the nearby Gulf Coast?
In short: it means nothing specifically, yet.
Last year, Hurricane Sally made a direct hit on Baldwin County: landfall at Gulf Shores at 4:45 AM on September 16th (almost exactly 16 years after Category Three Hurricane Ivan hit the exact same spot).
Hurricane Zeta, a Category Three at landfall in Louisiana hit Alabama hard as the storm’s core moved northeast across the state.
Climatology tells us the return period for a hurricane is around nine to eleven years on the Alabama, Mississippi and Northwest Florida Gulf Coast.
The return period for a major hurricane is longer: between two and three decades.
So while the law of averages tells us the odds are against a repeat of a Sally, Zeta – or even an Ivan or Katrina – in the 2021 season, we have to remember that averages are the middle of extremes.
For example, the return period on a hurricane near Lake Charles, Louisiana is 14 years. Hurricane Laura hit as a strong Category Four last August; Hurricane Delta came into the same area forty-one days later.
The lesson here? ‘Normal’ isn’t always reality.