The typical peak of hurricane season has arrived. Historically speaking, about two-thirds of Atlantic hurricane activity occurs between Aug. 20 and Oct. 10. The Gulf of Mexico contains record hurricane fuel, and the Atlantic’s waters are alarmingly hot. And yet, the Atlantic is silent.
No storms are in the forecast any time soon. In fact, the rest of August may go without a single named storm forming. And as September looms, many are wondering when — or if — the Atlantic will awaken again.
Forecasters are doubling down on their predictions for a hyperactive season, with enough named storms to exhaust the conventional naming list used by the National Hurricane Center. Researchers at Colorado State University are calling for a season nearly twice as active as average, as measured by a metric called ACE, or Accumulated Cyclone Energy. That measures how much energy storms churn through across a season.
In the near term, it looks like the calendar will flip to September uneventfully — but then the temporary reprieve will come to a grinding halt. Storm activity is likely to increase as next month begins, and a flurry of storminess is probable deeper into the month.
Here’s a breakdown of how the season has stacked up so far, and what’s still to come.
Has it actually been a slow season so far?
Believe it or not, no. The season did take a while to get going — the first named storm, Alberto, didn’t form until June 19. That’s the latest first-forming storm since 2014, when Arthur didn’t form until July 1.
Alberto was a fleeting tropical storm that impacted Tamaulipas, Mexico, with 50 mph winds between June 19-20.
But then came Beryl, a record-shattering Category 5 that reached peak intensity in the Caribbean on July 1. It was the farthest-south Category 4 on record in the Atlantic and the earliest-forming Category 5, as well as the fastest-intensifying storm on record before the month of September.
Given Beryl’s strength, size and longevity, it racked up enough ACE to represent nearly 29 percent of an average full season. Beryl hit Houston with 80 to 90 mph winds and a foot of rain on July 8.
Then Debby hit the Big Bend of Florida as a Category 1 hurricane overnight Aug. 4 into Aug. 5, and Ernesto hit Bermuda as a Category 1 on Aug. 17.
All told, storms so far in 2024 have already accounted for 45 percent of a normal season’s worth of ACE. That’s actually way ahead of schedule. On average, we’re barely getting started by Aug. 20; historically speaking, about 83 percent of a season’s ACE comes after Aug. 20.
That means that, despite the quiet stretch, we’re at our third most active season to date on record. (While hurricane records technically date back to the 1800s, weather satellites have only been around since about 1970.)
Why is there no Atlantic activity right now?
The Atlantic is empty at present, and according to the National Hurricane Center, “tropical cyclone activity is not expected during the next 7 days.” How is this possible in peak season?
A number of liming factors have cut back on storm activity:
- Dust from the Sahara. The SAL, or Saharan Air Layer, has lead to hot, dry and dusty air wafting over the eastern tropical Atlantic. That puts a lid on fledgling storms and inhibits development.
- Tropical waves farther north. Tropical waves are the “seeds” of tropical storms and hurricanes. They’re sprawling thunderstorm complexes. At this time of year, many tropical waves roll off the coast of Africa and eventually become named systems. As of late, the axis along which the line of tropical waves propagate has been displaced farther north. That means tropical waves are rolling into a drier air mass over cool waters. That’s why the tropical waves haven’t really been developing.
- Harsh upper-level winds. Winds over north central Africa have been stronger out of the east than normal, contributing to an active monsoon (moist weather pattern) there. While the monsoonal moisture is leading to more convection, or thunderstorm activity, any tropical waves get torn apart by the harsh winds aloft. That should change in the next week or two.
What to expect in the next two weeks
Philip Klotzbach, a researcher at Colorado State University, is anticipating near-normal Atlantic hurricane activity over the next two weeks. While the next week or so probably won’t produce anything, conditions will become more favorable for development in the next 10 days.
By then, a large-scale packet of thunderstorms called the MJO, or Madden-Julian Oscillation, will shift from the Indian Ocean eastward to near Indonesia. That should lead to a relaxation of harsh upper-level winds over Africa, allowing better-organized tropical waves to make it farther west across the Atlantic and be more primed to intensify.
What to know ahead, including some activity in the Pacific
From now through the end of August, not much will happen. But hurricane activity is likely to increase markedly into the first week of September. Calmer upper-level winds will make it easier for storms to form, and Saharan dust will become less of an issue.
Around the end of August, moreover, something called a Convectively Coupled Kelvin Wave might roll across the Atlantic. It’s like a broad overturning wave in the atmosphere, with sinking air on one side and rising air on the other. As the enhanced, or rising, branch of the wave moves over the ocean, it may further enhance the upward motion necessary for tropical waves to grow into named storms.
All told, quiet periods are supposed to happen, and while this one is seemingly extra quiet, it’s not terribly unusual. Signs point to a busy start to September. And the Gulf of Mexico is a powder keg of sorts, meaning any storm that moves into the Gulf could strengthen rapidly with favorable atmospheric parameters.
Simply stated, September might come in gently — but it won’t go out that way.
For now, the only systems to track are located in the Pacific. A developing storm may impact Hawaii by early next week.
