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Storm still trying to form in the Atlantic and slow developments in the Caribbean

Satellite image of tropic Atlantic and Gulf.
Satellite image of tropic Atlantic and Gulf. (WPLG)

The non-tropical system we’ve been following continues to wrap up in the Atlantic well southeast of Bermuda. Dry air has been slowing it down. There is a good circulation now, but the thunderstorms are all on the right side of the center. Still, all indications are it will pull itself together and it will become a depression or a named storm.

Because it’s a hybrid system – part like a tropical system and part like a nor’easter-type system – it will be called a Subtropical Depression or Subtropical Storm Epsilon.

The large system is forecast to meander around avoiding land for the next few days. It’s about 1,450 miles east of Miami. Around midweek, it should start heading to the north and northeast and out of the picture. The only question is whether Bermuda will once again be in the path.

Well south of Florida in the southern Caribbean, the barometric pressure is starting to fall. This map shows where the pressure is below normal in blue and above normal in the orangey brown. The zone between the extra-high pressure to the north and the lowering pressure to the south is quite windy. The stiff breeze off the ocean over South Florida has been caused by that.

Tropics air pressure map.
Tropics air pressure map. (WPLG)

The weather pattern will change about midweek, however. The strong high to the north will move away, and the atmospheric pattern over the southern Caribbean will become supportive of an organized low-pressure system developing there.

How the Caribbean low will evolve and move is still an open question. There have been big changes in the long-range computer forecast models, as there often are for systems that haven’t yet developed. The models that showed a strong storm developing, have generally backed off. Some still show it staying weak and drifting in the Caribbean or into the Gulf.

None of the long-range computer forecast models show a significant storm at this time, but big changes in the projections are still possible.

The bottom line: a definitive forecast is not possible at this point for late in the week. The large uncertainties related to forecasting weak or developing systems are in full force.

The consensus of the models is that the Caribbean system will have an effect on South Florida’s weather around Friday or Saturday. Whether that means extra moisture, drier air, or a windy storm is unknown, however. We have to let the situation develop a bit before we have a better idea.


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