SYSTEM CONSPIRING TO DAMPEN WEEKEND
At the very least, expect 2 to 4 inches of rainfall over next five days.
A tangle of clouds and showers stretching from the Cayman Islands to the Florida Straits is expected to bring widespread rain to Florida beginning today, and possibly build into something more through the weekend.
The National Hurricane Center has pegged the area as one to watch for tropical development, giving it, as of Thursday afternoon, a 50 percent chance of becoming a depression or tropical storm.
It has a small window to organize, with storm-shredding upperlevel winds becoming less accommodating for a tropical system early next week. But sea-surface temperatures in the high 80s in the Florida Straits and Gulf Stream are plenty warm for storm formation.
“This time of year, this is not unusual,” said Chuck Caracozza, a meteorologist with the National
Weather Service in Miami. “We’re still in hurricane season, and as we move into October, this is an area where tropical systems form.”
The next name on the 2017 tropical cyclone list is Nate.
“I wouldn’t trust this sneaky system one bit given what has happened so far in 2017,” said hurricane center scientist Eric Blake in a tweet. “Either way, a wet end of the week is coming for South Florida.”
There have been 13 named storms this season, one more than the final tally for an average year. On Wednesday, far away Hurricane Lee ramped up to a Category 3 storm. That makes it the fifth major hurricane of the season when a normal season has just two.
Dan Pydynowski, an AccuWeather senior meteorologist, said the highest chances for tropical development of the system nearing Florida are late tonight through Saturday after it pulls away from Cuba.
“If this thing becomes a depression or minimal tropical storm, you’ll have some wind to deal with, but by and large with things like this, the main threat is rainfall,” Pydynowski said. “The track is going to be very close to the east coast of Florida and that will help deter development.”
If a tropical storm did form
close to Florida’s coast, it wouldn’t be the first time this season that hurricane center forecasters had to make a tricky call.
An unassuming area of low pressure surprised the NHC and sleepy Floridians on July 31 when it gained tropical storm status at 8 a.m. — just three hours before making landfall near Anna Maria Island west of Bradenton as Hurricane Emily. The unusual combination of a summertime cold front and tiny low-pressure system over 86-degree Gulf of Mexico water led to Emily’s development.
Something similar can happen late in hurricane season when fall cold fronts dip down, sending thunder- storms into the Gulf where they can form into a tropical system.
Corene Matyas, an associate professor of geography at the University of Florida, said October tropical systems also have a tendency to produce prodigious rainfall.
“You still have a lot of moisture available in the deep tropics, but the middle latitude air masses are cooler and drier,” Matyas said. “When the moist tropical air pumps north into the cooler, drier air, that boundary can make a really broad area of rainfall.”
The Weather Prediction Center is forecasting 2 to 4 inches of rain for South Florida over the next five days, but rain bands that sit over one area can produce locally heavier showers.