• Talking the Tropics With Mike: Gulf disturbance to accelerate toward Fl. while strengthening

    By: Michael Buresh

    Updated:

    Oct. 18, 2019 - The "Buresh Bottom Line": Always be prepared!.....First Alert Hurricane Survival Guide... City of Jacksonville Preparedness Guide... Georgia Hurricane Guide.  

    STAY INFORMED: Get the * FREE * First Alert Weather app

    FREE NEWS UPDATES, ALERTS: Action News Jax app for Apple | For Android

    WATCH "Surviving the Storm"

    READ the First Alert Hurricane Center "Survival Guide"

    RECAP "Hurricane Dorian: A True Tropical Beast"

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

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

    * rain moves in from the south & southwest 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 early Sat. over the Central Fl. Panhandle not too far from Panama City 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 (8th 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.

    The system may be more subtropical (not purely tropical).  But that's mainly semantics & either way the impacts will be the same & very typical of landfalling tropical cyclones. 

    Most factors other than shear such as sea surface temps. (9th image below) & atmospheric moisture (11th 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.  It does appear on satellite data that some dry air is trying to wrap in from the west.

    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 WARNING 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]):

    Water vapor image shows dry air invading from the west.  Sure

    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:

    While parts of the Atlantic are cooler than avg., it's important to realize the water is still warm enough to support tropical systems....

    SE U.S. surface map:

    Surface analysis centered on the tropical Atlantic:

    Surface analysis of the Gulf:

    Caribbean:

     

    Global tropical activity:

    Next Up: