Odds Increasing for Development Next Week Over the Western Caribbean and Gulf

A tropical system could form by the early to middle part of next week, but the possible outcomes remain wide

On Thursday, the National Hurricane Center continued to raise the specter of tropical formation over the western Caribbean and southern Gulf of Mexico for the early to middle part of next week.

As we discussed in yesterday’s newsletter, the system expected to take shape beginning early next week will start within the sprawling Central American Gyre or CAG – a broad area of spin and storminess extending from the eastern Pacific into the western Caribbean and southern Gulf of Mexico. Tropical systems that form within the CAG are at least initially slow to come together so expect this will take a little time to shake out to start next week.

Our forecast models are all over the place right now, as we’d expect for such a broad region of low pressure that’s still nearly a week removed from organizing. The two camps right now are the European forecast model ensembles that suggest a weaker and more westward-tracking system into the central or southwestern Gulf next week versus stronger and more eastward-leaning scenarios shown by the American GFS ensembles.

Forecast low-pressure tracks through next Friday morning, September 27^th, from the overnight runs of the European model ensemble system (top) and American GFS model ensemble system (bottom). Each line represents a possible track scenario based on different starting conditions in the model to account for forecast uncertainty. The European solutions suggest a weaker and more westward-moving system, whereas the American GFS solutions lean east and stronger. Neither is more credible this far out, but the models do show the wide range of outcomes next week if a system forms. Credit: Weathernerds.org

Without knowing where or even if a system forms next week, neither forecast scenario is more credible, but they do illustrate the wide range of outcomes possible for anything that forms next week.

A reservoir of warm water ahead

Broadly speaking, the environment next week in the southern Gulf and over the western Caribbean looks conducive for development, with sprawling high pressure aloft and upper-level winds promoting storminess.

Water temperatures across the Gulf of Mexico are at near-record levels and the depth of the ocean fuel – as measured by the Ocean Heat Content – is the highest on record for the Gulf.

Ocean Heat Content or OHC – a measure of ocean heat stored below the surface – across the Gulf of Mexico for 2024 (thick red line) compared to all previous years available (thin gray lines). The Ocean Heat Content in the Gulf is the highest on record for middle September. Credit: Brian McNoldy/University of Miami

So if something gets its act together next week, there’s certainly the possibility for strengthening. For now, however, we need to stay patient and watch the trends this weekend. Check back on the forecast periodically if you live along the Gulf Coast or Florida peninsula – including here in South Florida – and have a plan in the event a storm threatens next week.

Mostly quiet elsewhere in the Atlantic

Things will stay mostly quiet elsewhere in the Atlantic into next week. The remnants of Tropical Storm Gordon are moving northward into the open central Atlantic and, while some redevelopment is possible over the next few days, it’ll be no threat to land.

Another area of low pressure west of Gordon’s remnants has a low chance of development the next few days but like it’s closest neighbor, will meander over the open Atlantic waters.