Atlantic Hurricane Season Had A Rare August Shutout

The Atlantic hurricane season didn't produce a single storm in August for the first time in 25 years.

The last named storms - Bonnie, then Colin - briefly made their appearances in the Atlantic Basin in the first days of July.

F​ollowing those, a pair of systems attempted to form in the western Gulf of Mexico in August, but each failed to become tropical depressions or storms.

T​ropical Storm Danielle formed, but on Sept. 1 over the North Atlantic.

Only one other August in the last 56 years of the satellite era failed to produce a single tropical storm.

That was in 1997 when an El Niño rapidly developed into one of the strongest on record by fall. El Niños tend to produce increased sinking air and wind shear in parts of the Atlantic Basin, which lead to fewer tropical storms and hurricanes.

Another year just prior to the satellite era - 1961 - also failed to produce an August storm.

Except for 1988, i​t's also the quietest start to any Atlantic hurricane season in the satellite era, as measured by a metric called the ACE index, according to Steve Bowen, meteorologist at Aon.

W​hat's particularly stunning about this quiet period is that it happened during a La Niña, which typically produce a much more conducive environment of lower wind shear. This La Niña is solidly in place for what appears to be an unusual third year in a row.

Over the past 30 years, an average August has produced from 3 to 4 storms.

Last August, seven named storms formed, four of which eventually became hurricanes.

Among those four included Grace, which became the strongest known hurricane to strike Mexico's Veracruz state, and Ida, which slammed Louisiana at Category 4 intensity, then flooded out parts of the Northeast.

Why So Quiet?

It's normal for the hurricane season to start out slowly. You can see that on the graph below.

According to the National Hurricane Center, an average season would have produced only six storms by the end of August.

That's because, in June and July, two nemeses of tropical storms - wind shear and dry air - are usually in abundant supply.

In August 2022, those twin nemeses have been unusually stubborn.

Frequent dry air intrusions known as Saharan Air Layers (SAL) push from Africa westward across the Atlantic from June through early August, suppressing thunderstorms needed as the building blocks for tropical development.

But the TUTT has also allowed dry air to linger through August from the Caribbean Sea to the so-called main development region between the Lesser Antilles and Africa.

These have made the tropical Atlantic Basin much more hostile for development than the usually favorable environment in a La Niña hurricane season.

Quiet Seasons Usually Don't Last

What some meteorologists refer to as a "light switch effect" when the slumbering tropics suddenly become much more active has now happened in September.

While the strong El Niño of 1997 only allowed another three storms and one hurricane to form the rest of the hurricane season after August, other slow start seasons have historically delivered a punch from September on.

In 1961 - the only other "0 for August" hurricane season since 1950 - 11 storms formed from September on, eight of which became hurricanes. That included Category 4 Hurricane Carla's pummeling of the Texas Coastal Bend.

W​e're also headed into September still waiting for the season's first Atlantic Basin hurricane.

There were only six other seasons in the satellite era that failed to generate a hurricane through August - 1967, 1984, 1988, 2001, 2002 and 2013.

From September onward, those six seasons generated an average of 9 to 10 storms, 5 of which became hurricanes. That's about what you'd expect in an average season.

Among the notable hurricanes in those "quiet through August" seasons included Gilbert in 1988, the most intense Atlantic Basin hurricane by pressure, at the time (later surpassed by Wilma), and 2002's Hurricane Lili in Louisiana, a billion-dollar hurricane in its own right.

I​n an average hurricane season, 70% of activity occurs from Sept. to the end of the season, according to data compiled by Phil Klotzbach.

So, don't assume this quiet stretch is Mother Nature giving you an all-clear for the rest of the season.

Make sure you develop or refresh your hurricane plan now. That includes finding out if you live in an evacuation zone.

It only takes one hurricane strike to turn what was a quiet start to the season into one you'll never forget.

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