TAMPA, Fla. (WFLA) — It is becoming more likely that a tropical system may try to form in the western Caribbean over the weekend and move into the eastern Gulf early next week. This may bring impacts to the Tampa Bay area by Tuesday.
At this point, the details are very uncertain, and it may be nothing more than disorganized tropical moisture, but it bears watching as a few of the computer models are showing a named system moving towards Florida’s Gulf Coast.
The system has a 20% chance of development over the next seven days, according to the National Hurricane Center.
The system in question is nothing more than a weak disturbance on the Pacific side of Central America. It is expected to move north crossing into the western Caribbean this weekend. At this point it has a chance to gradually develop into a tropical storm if it remains over the water.
While much of this is unclear, at this point it does not look like it will be a strong storm – but a named tropical system is certainly possible. Still any tropical system over record hot Gulf waters can spin up into something stronger under the right conditions.
Since the Tampa Bay area is in severe to extreme drought — 10″ to 15″ inches below normal in rainfall for the year so far — we could use a good soaking of rain. But the concern is it may come with a developed tropical system of some sort.
Right now there is substantial wind shear across the Gulf of Mexico, acting as a wall, which would shred any tropical system that moves north. However, some models show this shear weakening enough to provide a narrow window of opportunity.
At the same time there is a suitable environment over the western Caribbean for development, namely an upper level high pressure which provides a nurturing environment with light winds for the system to organize with limited interruption.
Below you can see how the upper level wind and shear evolves on the European model, which supports development of the system. In the case of the European model it weakens the shear and develops an upper level low over the central Gulf. That upper low steers the storm north and at the same time provides some support to strengthen the storm.
It should be noted that the European model is the most aggressive model. The American model does not show this. With that said, some other models do show development, although not as strong as the Euro model. The truth probably lies somewhere in between.
Below is the European ensemble forecast from Weather Nerds. This is various model runs of the European – essentially family members – that are each tweaked to show different outcomes. There is general agreement within the Euro family that a storm could take shape.
What is clear is that the situation is very uncertain right now, and the outcome could range from some disorganized tropical moisture, to a modest tropical system from Tuesday into Wednesday.
The Tampa Bay area really needs the rainfall and so tropical moisture is needed to make a dent in the drought. It seems likely that regardless of tropical development, moisture will be heading north and rain coverage should increase by next Tuesday-Thursday.