A quick look ahead to the 2024 hurricane season
There’s been chatter about how the stars may be aligning for an elevated chance of a busy hurricane season in 2024. This conversation is primarily driven by: 1) the Tropical Atlantic remaining much warmer than average even after a busy 2023; 2) El Nino winters and springs tending to have weak trade winds across the Tropical Atlantic, favoring continued (or increased!) Atlantic warmth; and 3) the rising odds of a return to La Nina conditions in the second half of 2024. As a reminder, whether La Nina or El Nino is active during the peak of hurricane season plays a huge historical role in modulating U.S. landfall risks, with major hurricane landfalls around three times as frequent during La Nina versus El Nino seasons.
With 2023’s El Nino rising into the ranks of the five strongest fall +ENSO events since 1950, it’s worth noting that the next hurricane seasons following those El Ninos average about 20% more Accumulated Cyclone Energy than the “normal” year. With that in mind, I put together an early version of WeatherTiger’s seasonal ACE model, using the current state of the ocean and atmosphere to project an objective first look at the odds for the 2024 season. The exceedance curve is below:
Overall, this early forecast has about a 55% chance of 2024 ACE landing in the top third of seasons since 1950, a less than 10% chance of bottom third ACE, and a most likely outcome of 130-135 ACE (50-year normal ACE is around 100). This model is conservative, and 130-135 ACE is the highest December forecast since its prediction for 2017 (forecast 172, actual 225). While I wouldn’t read too much into it at this point, our model does provide some quantitative support for the qualitative arguments of why 2024 may be busy. I’ll have a more formal outlook for the season in early April.
The ENSO whisperer
As demonstrated above, the major influence on Hurricane Season ’24 is the strong El Nino event, likely peaking right about now. WeatherTiger’s ENSO Whisperer model run for December shows this potent Nino will be on the way out by spring, with a most probable return of neutral ENSO conditions in April. This is a typical fate of strong El Nino events, which seldom last more than 6 months.
The bigger question lurking deeper in 2024 is whether a full-fledged La Nina will develop over the summer and fall— so far, that’s not showing up in WeatherTiger’s model, which runs through June. ENSO forecast skill beyond the so-called spring predictability barrier is low, but a number of the seasonal climate models are increasingly bullish on La Nina development by mid-year. I’ll be watching ENSO carefully through the off-season, as a faster Nina development ups the odds of a busy 2024 Atlantic hurricane season.
For Florida specifically…
As the short-term forecast hints, the first quarter of 2024 likely will be mild and wet overall. WeatherTiger’s model for January-February-March (DJF) average temperatures in Florida relative to normal calls for around a 45% chance of temps within 1F of average, with a 20% chance of cooler than normal and 35% chance of warmer than average temperatures. The best chance of a run of cooler than normal temperatures is likely between mid-January and early February.
In terms of rainfall, recent precip has worn the fall drought region back to just a nubbin in west-central Florida, and near-normal or above-normal rainfall in the state is overwhelmingly likely through March. There is about a 10% chance of less than average rainfall, and a 45% chance each of wetter than normal and near-normal conditions, with Florida as a whole likely to see about 115% of typical winter rainfall.
‘Tis the season
And finally, this December to remember, you can make a gift subscription to this newsletter your personal Lexus with an oversized bow on it. If WeatherTiger’s Hurricane Watch has brought you joy in 2023, you can share that joy via a gift subscription at a special 23% off rate through the end of December. If it has brought you agony, you can inflict that on an enemy for 23% off. Endless possibilities. Click below for the sale, ending 12/31.
Thanks for reading. Merry Christmas and happy holidays, and I’ll catch you in 2024.
Eeegads. For us it's the inflatable Clark Griswold from Christmas Vacation. Is it wrong if I'm not concerned about "him" being taken away with the wind?
Happy Holidays Doc. My family and many friends (who put with my diatribes) are blessed by your energy and guidance!