Weather Nerd

A major late-season threat in the Caribbean

Just when you (and I) thought hurricane season was effectively over, Tropical Depression Seventeen has formed off the coast of Nicaragua — and it could be a major threat to the Cayman Islands and Cuba this weekend.

Although T.D. 17 currently has maximum sustained winds of just 35 mph, conditions are ripe for strengthening, with warm waters and extremely low wind shear. Tropical Depression 17 is expected to become Tropical Storm Paloma sometime Wednesday, and Hurricane Paloma within 48 hours. After that? Watch out:

[B]oth the GFDL and HWRF models … predict TD 17 will pass though the Cayman Islands on Saturday morning as a Category 2 hurricane, and strengthen to a Category 3 or 4 hurricane by landfall Sunday morning in central Cuba.

Other computer models, it should be noted, are less aggressive than the GFDL and HWRF, which is unsurprising; those models are not infrequently high-end outliers when it comes to intensity forecasts. Nevertheless, there is a real chance of a major November hurricane for the Caymans and Cuba (with some possible impacts on Jamaica). Dr. Jeff Masters writes, “I give TD 17 a 70% chance of becoming a hurricane, and a 40% chance of becoming a major hurricane.” 

Of course, even if that 40% comes to fruition, it is possible proto-Paloma could become a major hurricane, but then weaken before landfall. That seems to be what Alan Sullivan is tentatively anticipating.

Alternatively, it is also possible the storm might not be picked up at all by the trough of low pressure that’s expected to take it toward Cuba, in which case it could meander near land or over upwelled waters, potentially inhibiting its development. But that scenario gets less likely as TD 17 gets stronger, because the storm is more likely to “feel” the trough if it is better organized.

In any case, while it’s too early to make any definite predictions, this one definitely bears watching.