Tropical System Expected to Form, Strengthen Over the Caribbean this Weekend

Florida could be in the crosshairs next week, but it’s too soon to know what threat it could pose

A disturbance tracking south of Jamaica Wednesday morning – designated Invest 99L by the National Hurricane Center – is expected to organize into Tropical Storm Sara over the coming days and could strengthen into a powerful hurricane by this weekend as it hangs about off the coasts of Honduras and Nicaragua.

Water temperatures in the formation zone are almost as warm as you’ll find them for the time of year – upper 80s to near 90 degrees Fahrenheit still – and the upper-level wind pattern will be unusually conducive for November.

The ceiling for strengthening will be mostly limited to how much interaction the system has with parts of Central America or southern Mexico over the weekend and into the start of next week.

By next week, forecast models show that the system will turn northward to the Gulf of Mexico and hang a hard right toward Florida for next Tuesday into Wednesday (November 19-20).

The question for us in Florida will be how organized it remains by the time it heads our direction.

Escape doors closing

In Monday’s newsletter, we discussed three doors the developing system could take, including an escape route to the east through the islands and out into the open Atlantic. Today that first exit ramp looks closed, as models suggest the cold front descending into the Caribbean this weekend may temporarily stall the storm’s westward progress but won’t be enough to pull it out to sea.

Which means future Sara will be left behind and guided by a building area of high pressure to its north and east, which will steer it back west by Sunday and bend it northwestward toward Belize and the Yucatán for next Monday.

The biggest question in the days ahead is does the front pull the system far enough east to keep it over water this weekend, or does future Sara get tangled up with Central America sooner, disrupting its circulation and weakening it before it moves into the Gulf?

Neither scenario is necessarily good for Nicaragua and Honduras, as the system’s close proximity to Central America will likely bring significant impacts regardless, but given the conducive environment this weekend, entanglements with land could lessen, though perhaps not completely eliminate, the threat to Florida next week.

Watching and waiting in Florida

Assuming the system survives any interaction with Central America this weekend or the Yucatán Peninsula on Monday and early Tuesday, it will round high pressure into the Gulf and may slingshot quickly toward Florida for Tuesday into Wednesday.

How far north it gets in the Gulf and how quickly it’s picked up by another approaching cold front will determine where it heads across the state.

Odds of the center of 99L (future Sara) tracking to within about 100 miles of a given location based on our most reliable global forecast models. The American GFS favors a track closer to South Florida while the European model favors a track farther up the west coast of Florida and Big Bend. It’s too soon to know what threat the system might pose as it nears Florida for the middle part of next week. Credit: Tomer Burg/University of Oklahoma

The possibilities are wide – from a hurricane to storm remnants anywhere from South Florida to the Big Bend – so we’ll need to stay patient and check back on the forecast.

As we mentioned yesterday, weather patterns in late fall are volatile – much more so than during the summer – and prone to big changes this far out. We’re still a solid 6-7 days removed from any possible impacts in Florida – an eternity in forecast hours – and the system hasn’t formed yet, so expect things will change.

For now, we’ll stay aware and monitor the trends, especially over the weekend. Once a system forms, we should start to get a better handle on where things stand for us in Florida.