The unusual late season storm system coming together east of the Bahamas was formally christened Nicole by the National Hurricane Season during the pre-dawn hours Monday.
The storm will move toward Florida Monday and Tuesday while gradually organizing and is expected to bring nor’easter-like impacts – including dangerous seas, life-threatening surf and rip currents, and minor to moderate coastal flooding – to South Florida for Tuesday and Wednesday.
Tropical Storm Watches will likely be issued for the east coast of Florida later Monday.
The initial designation as a subtropical storm practically means the surface circulation is broad and storminess is very spread out in a wide comma-shaped pattern stretching clear down into the eastern Caribbean.
Closer to its center, Nicole’s taken on a dumbbell appearance, with showers north and south of the surface spin, rather than directly over the circulation as with most purely tropical storms.
Because of its sprawling subtropical nature, Nicole will take some time to bake, but it should gradually transition to a more familiar tropical storm as it nears Florida’s east coast Tuesday and Wednesday, where still-warm waters will help trigger storminess closer to the circulation center.
While the official NHC forecast brings Nicole to a borderline hurricane, it’s worth noting our reliable intensity guidance are in good agreement with keeping the storm near or below hurricane strength around the time of landfall in Florida.
If Nicole comes ashore Florida’s Atlantic coast as a hurricane, it would be the latest hurricane landfall on record for the Florida peninsula (Hurricane Kate, which struck the Florida panhandle on November 22nd, 1985, is the latest landfalling Florida and U.S. hurricane).
The exact details of the inland impacts for Monroe, Miami-Dade and Broward counties will hinge largely on where the center of the lopsided circulation comes ashore.
Despite the potential for a strong tropical storm or even borderline hurricane near landfall mid-week, the orientation of upper-level winds will likely shunt more serious inland hazards like heavy rainfall north of the the center.
The current forecast scenario, with landfall north of Palm Beach County, could limit the heavy rainfall potential for our area. Of course, even a few days out, the average track error is about the distance from Miami to Jupiter, so we’ll need to watch those forecast trends closely.
By Thursday, the coastal threat should begin to subside for southeastern Florida as winds turn offshore. Winds will gradually relax by the end of the workweek as drier air wraps around from the west side of the storm.
As we discussed in previous newsletters, the storm will be approaching around the full moon on Tuesday, which will bring some of the highest tides of the season.
Locally, we’ll be watching the coastal flood threat during the morning high tide in particular on Tuesday and Wednesday when we can expect widespread minor to moderate coastal flooding. Dangerous surf and life-threatening rip currents will persist for much of the week.
By Friday, the storm will get picked up by an approaching cold front and accelerate northeastward through the Carolinas and out to sea over the weekend.
The passage of the cold front through South Florida next weekend will also bring back the protective wind shear to our neck of the woods that typically keeps storms away by this point in the season.