Tropical Storm Isaias. Advisory #23A

BULLETIN
Tropical Storm Isaias Intermediate Advisory Number 23A
NWS National Hurricane Center Miami FL       AL092020
800 PM EDT Sun Aug 02 2020

...ISAIAS CONTINUES MOVING NORTH-NORTHWESTWARD JUST OFFSHORE OF THE
EAST-CENTRAL FLORIDA COAST...


SUMMARY OF 800 PM EDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...28.2N 79.7W
ABOUT 55 MI...90 KM ESE OF CAPE CANAVERAL FLORIDA
ABOUT 385 MI...620 KM S OF MYRTLE BEACH SOUTH CAROLINA
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...NNW OR 345 DEGREES AT 9 MPH...15 KM/H
MINIMUM CENTRAL PRESSURE...993 MB...29.32 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:

None.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* Edisto Beach South Carolina to Cape Fear North Carolina

A Storm Surge Watch is in effect for...
* Cape Fear to Duck North Carolina
* Pamlico and Albemarle Sounds

A Hurricane Watch is in effect for...
* South Santee River South Carolina to Surf City North Carolina

A Tropical Storm Warning is in effect for...
* Sebastian Inlet Florida to Ocracoke Inlet North Carolina

A Tropical Storm Watch is in effect for...
* Ocracoke Inlet North Carolina to Watch Hill Rhode Island
* Pamlico and Albemarle Sounds
* Chesapeake Bay
* Tidal Potomac River
* Delaware Bay
* Long Island and Long Island Sound

Interests elsewhere along the northeast coast of the United States
should monitor the progress of Isaias.  Additional watches or
warnings may be required tonight or early Monday.

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
during the next 36 hours in the indicated locations. For a depiction
of areas at risk, please see the National Weather Service Storm
Surge Watch/Warning Graphic at hurricanes.gov.  This is a
life-threatening situation.  Persons located within these areas
should take all necessary actions to protect life and property from
rising water and the potential for other dangerous conditions.
Promptly follow evacuation and other instructions from local
officials.

A Storm Surge Watch means there is a possibility of life-
threatening inundation, from rising water moving inland from the
coastline, in the indicated locations during the next 48 hours.

A Hurricane Watch means that hurricane conditions are possible
within the watch area.  A watch is typically issued 48 hours
before the anticipated first occurrence of tropical-storm-force
winds, conditions that make outside preparations difficult or
dangerous.

A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area, generally within 36
hours.

A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area, generally within 48 hours.

For storm information specific to your area in the United
States, including possible inland watches and warnings, please
monitor products issued by your local National Weather Service
forecast office. For storm information specific to your area
outside of the United States, please monitor products issued by
your national meteorological service.


DISCUSSION AND OUTLOOK
----------------------
At 800 PM EDT (0000 UTC), the center of Tropical Storm Isaias was
located by a NOAA Hurricane Hunter aircraft near latitude 28.2 
North, longitude 79.7 West.  Isaias is moving toward the 
north-northwest near 9 mph (15 km/h), and this general motion is 
expected to continue through tonight.  A turn toward the north and 
north-northeast along with an increase in forward speed is 
anticipated on Monday and Tuesday.  On the forecast track, the 
center of Isaias will pass just to the east of the Florida east 
coast through tonight.  The center of Isaias will then move offshore 
of the coast of Georgia and southern South Carolina on Monday, move 
inland over eastern South Carolina or southern North Carolina Monday 
night and move along the coast of the mid-Atlantic states on 
Tuesday.

Maximum sustained winds are near 70 mph (110 km/h) with higher
gusts.  Some fluctuations in strength will be possible during the
next 36 hours, but Isaias is expected to be a strong tropical storm
when it reaches the coast of eastern South Carolina or southern
North Carolina Monday night.  Slow weakening is forecast after
Isaias makes landfall in the Carolinas and moves across the U.S.
mid-Atlantic region late Monday and Tuesday.

Tropical-storm-force winds extend outward up to 115 miles (185 km)
from the center.  NOAA buoy 41009, located just off the coast of 
Cape Canaveral, recently reported a sustained wind of 45 mph (72 
km/h) and a gust of 54 mph (87 km/h).  A Florida Institute of 
Technology observing station at Sebastien Inlet measured a sustained 
wind of 39 mph (63 km/h) and a gust of 48 mph (78 km/h) during the 
past couple of hours.

The minimum central pressure estimated from NOAA Hurricane Hunter
aircraft observations is 993 mb (29.32 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Isaias can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4, WMO header WTNT44 KNHC, and
on the web at www.hurricanes.gov/text/MIATCDAT4.shtml.

STORM SURGE:  The combination of a dangerous storm surge and the
tide will cause normally dry areas near the coast to be flooded by
rising waters moving inland from the shoreline.  The water could
reach the following heights above ground somewhere in the indicated
areas if the peak surge occurs at the time of high tide...

Edisto Beach SC to Cape Fear NC...2-4 ft
Sebastian Inlet FL to Edisto Beach SC...1-3 ft
North of Cape Fear NC to Kiptopeke VA including Pamlico Sound,
Albemarle Sound, Neuse River, Pamlico River, Chesapeake Bay, and
the Tidal Potomac River...1-3 ft

The deepest water will occur along the immediate coast in areas of
onshore winds, where the surge will be accompanied by large waves.
Surge-related flooding depends on the relative timing of the surge
and the tidal cycle, and can vary greatly over short distances.
For information specific to your area, please see products issued
by your local National Weather Service forecast office.

WIND:  Hurricane conditions are possible in the watch area in South
and North Carolina Monday night and early Tuesday.

Tropical storm conditions will spread northward within the Tropical
Storm Warning area from Florida to North Carolina through Monday
night.

Tropical storm conditions are possible in the Tropical Storm Watch
area beginning on Tuesday.

RAINFALL: The following rainfall accumulations are expected along
and near the track of Isaias:

Northwest Bahamas: Additional 1 to 3 inches, isolated storm totals
12 inches.

Eastern Florida: Additional 1 to 3 inches, isolated storm totals
4 inches.

Coastal Georgia: 1 to 2 inches.

Carolinas and the Mid-Atlantic: 3 to 6 inches, isolated maximum
totals 8 inches.

Southeast New York and much of New England: 2 to 4 inches, isolated
maximum totals 6 inches.

Heavy rainfall from Isaias will continue to result in potentially
life-threatening flash flooding in the Northwestern Bahamas through
tonight. Flash and urban flooding, some of which may be significant
in the eastern Carolinas and the Mid-Atlantic, is expected through
midweek along and near the path of Isaias across the East Coast of
the United States. Widespread minor to isolated moderate river
flooding is possible across portions of the Carolinas and the
Mid-Atlantic.

SURF:  Swells generated by Isaias are affecting portions of the
Bahamas and the southeast coast of the United States and will spread
northward along the U.S. east coast during the next couple of days.
These swells are likely to cause life-threatening surf and rip
current conditions.  Please consult products from your local weather
office.

TORNADOES:  A few tornadoes will be possible over coastal South
Carolina during the afternoon and evening on Monday, and across
eastern North Carolina Monday evening and overnight.

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