Talking the Tropics With Mike: Disturbance over the Western Gulf likely to become Nestor

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** A tropical disturbance - likely to soon become "Nestor" - over the Gulf of Mexico will move near the Gulf Coast Fri. night then inland over Fl. & Ga. Saturday with bands of heavy rain & possibly isolated tornadoes along with gusty winds & rough seas & surf from near New Orleans to near Jacksonville **

Specifically for Jacksonville/NE Fl./SE Ga.:

* rain moves in from the south & southwest by Fri. evening & intensifies overnight into Saturday

* heavy rain at times with amounts averaging 1 - 2", locally 3"+

* isolated tornadoes later Fri. night into Saturday

* gusty winds on the order of 15-30 mph sustained but gusts of 40+ mph

* rough seas & surf - a high rip current risk at area beaches

* rapidly improving weather Sat. night into Sunday

Low pressure has formed over the Western Gulf of Mexico & is likely to become a tropical storm before making landfall Fri. night over the Central Fl. Panhandle then moving inland Sat. over Georgia. The exact location & intensity will determine the magnitude of impacts. This will be a fast mover which should help in terms of how strong the system might become (less time over water).... & will keep rainfall amounts lower - but still heavy - than might typically occur with a landfalling tropical cyclone.

Indications are that the system will be hampered - at least some - by strong shear out of the west/southwest at more than 30-40 mph (3rd image below). However, the disturbance will be moving east/northeast in tandem with the shear - in addition to upper level divergence (splitting of the winds) which may allow for steady strengthening. The shear is likely to make the system heavily weighted on the north & east side. In other words, the heavy rain & strongest winds will be in the top (north) & right (east) quadrants.

A front is also stalled out over the Northern Gulf. If the disturbance attaches itself with the front then the system may be more subtropical. But that's mainly semantics & either way the impacts will be the same & very typical of landfalling tropical cyclones.

Most other factors such as sea surface temps. (5th image below) & atmospheric moisture (7th imgage) are more than adequate for tropical development. And there is a pocket of high oceanic heat content (warm water to a deep depth) over the Central Gulf.

Anyone living in - or traveling through - the corridor from New Orleans to Jacksonville through Saturday & as far north as much of Georgia & parts of the Carolina's through Sunday should expect impacts from what will likely become "Nestor".

A storm surge WATCH is in effect for the Big Bend of Fl. to as far south as just north of Tampa....

Shear (red lines indicate "strong" shear):

Deep oceanic heat content (warm "eddy" over the Central Gulf):

Sea surface temps. (red = warm [well into the 80s]):

Mid & upper level moisture (colored areas = dry air):

Rainfall forecast through the weekend shows the Gulf disturbance bringing heavy rain northeast all the way to the Gulf Coast:

Atlantic dust:

2019 names..... "Nestor" is next on the Atlantic list (names are picked at random... repeat every 6 years... historic storms are retired (Florence & Michael last year) & Dorian is almost certain to be next:

East Atlantic:

Mid & upper level wind shear (enemy of tropical cyclones) analysis (CIMMS). The red lines indicate strong shear of which there is plenty across the Atlantic at the moment:

The Atlantic Basin:

Water vapor imagery (dark blue indicates dry air):

Deep oceanic heat content is extreme over the NW Caribbean:

Sea surface temp. anomalies show a warm Gulf of Mexico, Central & Northwest Atlantic while the "Main Development Region" (MDR) remain cooler than avg. A pocket of cool water temps. has expanded over the SW Atlantic including the Bahamas: