Quote:
Back on May 31st, the day before the official start of the Atlantic Hurricane Season of 2024, I posted to our community contest the following Quote:
My read of the preseason predictors suggests roughly 75% odds of an above-average to record-setting season this year, about a one-in-five chance of an average season, and a very low but non-zero chance of a below-average season. I think the factor that could most impede or even prevent a very active season is the Saharan Air Layer (SAL), which is notoriously hard to predict this early but that doesn't seem particularly in play, at least not yet.
The caveat was not looking for a preemptive excuse in case of a bad call, although it certainly helps in that regard, but my reasoning that my own forecast could bust. At that time for the purpose of our annual contest, I best guessed "26 Storms 13 Hurricanes 5 Majors," but it was already apparent that there would be a risk of a dry, dusty season, or for at least part of the season. Nonetheless, the information available to me at the time as well as all others, including the pros, rolled out a forecast of a hyperactive hurricane season, with some agencies putting out mind-boggling totals not far from my own.
The darn thing is, even though the Atlantic is rip-roaring hot relative to average, and the eastern Pacific is in a "cool neutral" state relative to average, once a pattern sets up that shuts one basin off can quickly conspire to enhance another, regardless of background ENSO state. I believe we have been witnessing this in 2024 ever since the rapid ramp-up in June collapsed.
Indeed, as was my preseason caveat, an active Saharan Air Layer (SAL ~ Saharan dry and dusty air), looks to be culprit #1. In fact, SAL this year has been swinging wildly between well below average earlier in the year, to more recently, during July and August, even record-setting high. Tropical cyclones do not like dry, dusty air. At all.
And often working in tandem with this SAL has been an ITCZ setup that is further north than ideal, sending would-be TC seedling waves immediately into hostile SAL territory, even also over anomalously cooler SSTs just off the coast of Africa closer to and around the Canary Islands. Much too far north to worry those west of the 55th Meridian West under most circumstances.
Yet another feature that has served to choke would-be Atlantic TCs the past two months has been too much of a good thing. Strong high pressure across the North Atlantic that had been expected to moderate westerly shear, has actually resulted in easterly shear.
And to come full circle, waves that somehow traveled west at a more southerly latitude have usually been held in check and forced to cross over into the East Pac, where they still found very warm waters, despite the lack of El Niño. And often when thunderstorms and hurricanes are active in the East Pac, shear gets higher still over the Western Atlantic.
Some years, as recently as 2022 for example, the seasonality of SAL and other inhibiting factors that choked much of the activity July through August gave up the ghost, leading to a very busy rest of the season starting in September, and this is very plausible. I have some reservations, but think the odds of this happening here are closer to 60/40 in favor.
It's complicated beyond my uneducated mind's comprehension. I go with gut feelings when I don't fully understand the underlying reasons. Me-gut is suggesting that anything that can make it to the GOMEX, Caribbean or Bahamas (TCs or early fronts) may potentially/explosively intensify.. I downgraded my call too, but still think that once things get going in September, October and early November may make up for the total lack of activity the last 3 weeks in August.
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CoCoRaHS Weather Observer (FL-VL-42) & Surf Forecaster: https://www.surf-station.com/north-florida-surf-forecast-3/
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