Talking the Tropics With Mike: Florence - a depression -turns north, still producing very heavy rain

Sept. 17, 2018 — The "Buresh Bottom Line": Always be prepared!.....First Alert Hurricane Survival Guide... City of Jacksonville Preparedness Guide... Georgia Hurricane Guide.

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FLORENCE - landfall - as Cat. 1 - early Fri.... edge of eyewall at 6am... center of the eye at 7:15am EDT at Wrightsville Beach, NC very near Wilmington..... moving ever so slowly westward & weakening to a tropical depression

LOCAL - JACKSONVILLE & VICINITY - FLORENCE IMPACTS:

* NONE

Rainfall estimated by Doppler Radar through early Sunday:

Remarkable landfall forecast from the NHC 5 days in advance. Forecast on the left is the 5am advisory Sun., 09/09... image on the right is reality early Fri., 09/14:

"Florence" - a named storm for the 14th straight day Fri. - became the 3rd hurricane, 1st "major" of the '18 Atlantic season Tue.... went Cat. 3 then briefly Cat. 4 last Wed. ... fell apart in the face of shear & dry air Thu.... continues moving into the Western Atlantic & made the expected comeback reaching Cat. 4 strength again Mon. The tropical cyclone made the important turn northwest reaching Jacksonville's latitude BUT hundreds (400+) of miles to the east - late Wed./Wed. night. Florence went through some serious structural alterations Wed. probably due to nearby dry air & some shear which has caused weakening & never could fully recover. Florence made landfall early Friday as a Cat. 1 & the underside (south portion) of the circulation is pretty quickly weakening while the north & east quadrants remain relatively strong. Such an evolution is not uncommon with landfalling tropical cyclones as dry air is often first ingested from the west due to the counter-clockwise circulation.

Despite the general weakening before landfall (some mistakenly took this as a sign that the storm wouldn't be "that bad", Florence has been - & will be - a big hit on the Carolina's: Major to severe impacts can be expected & - in some instances - truly catastrophic. Very heavy rain has - & will - cause widespread flooding.

Florence - soon to be post-tropical - is making the turn north then will turn rather sharply east/northeast exiting into the NW Atlantic off New England Tue.

Flooding will follow the path of the post-tropical low pressure from Eastern Tennessee northeastward through parts of Virginia, Pennsylvania, Maryland, New York & Massachusetts through the middle of the week! River flooding will lag the flash flooding reaching record levels in some areas.

Bottom line: Don't panic but always be prepared.....

1-3 day rainfall forecast shows the band of heavy rain spreading from the Appalachians into New England:

Tropical cyclone record rainfall (for a single storm) may be broken in some states:

Wide view of the busy Atlantic Basin. Joyce developed over the N. Atlantic Wed. & will soon be post-tropical. Isaac - has degenerated into a tropical wave over the Caribbean... Helene has become extra-tropical. Low pressure may try to develop east of the Bahamas this week & could try to gradually take on some tropical characteristics - something to watch.

E. Atlantic:

Isaac leftovers:

Joyce:

Mid & upper level wind shear (enemy of tropical cyclones) analysis (CIMMS). The red lines indicate strong shear. Note weaker shear in the path of Florence over the W. Atlantic while there's much stronger shear over the Caribbean......

The Atlantic Basin....

Caribbean:

Gulf of Mexico:

Water vapor imagery (dark blue indicates dry air) - notice the dry air right up against Florence:

Deep oceanic heat content is seasonably high over the Caribbean, Gulf of Mexico & SW Atlantic as one would expect now that we're near the peak of the hurricane season....

Sea surface temp. anomalies show a general recent warming over a good portion of the Atlantic Basin including rather dramatic warming east of the Caribbean & near the NE coast of S. America ....