Hurricane Isaias Advisory 27A

BULLETIN
Hurricane Isaias Intermediate Advisory Number 27A...Corrected
NWS National Hurricane Center Miami FL       AL092020
800 PM EDT Mon Aug 03 2020

Corrected to add extent of hurricane-force winds and surface ob

...ISAIAS REGAINS HURRICANE STRENGTH AND IS EXPECTED TO MAKE
LANDFALL TONIGHT WITH DANGEROUS WINDS AND STORM SURGE...
...STRONG WINDS AND HEAVY RAINFALL LIKELY FROM THE EASTERN
CAROLINAS TO THE MID-ATLANTIC COAST TONIGHT AND TUESDAY...


SUMMARY OF 800 PM EDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...32.8N 79.0W
ABOUT 60 MI...100 KM E OF CHARLESTON SOUTH CAROLINA
ABOUT 60 MI...100 KM S OF MYRTLE BEACH SOUTH CAROLINA
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...NNE OR 15 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...988 MB...29.18 INCHES


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

The Tropical Storm Warning south of Edisto Beach has been
discontinued. The Storm Surge Warning south of Folly Beach has been
discontinued.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Storm Surge Warning is in effect for...
* Folly Beach South Carolina to Cape Fear North Carolina
* Pamlico and Albemarle Sounds, including the Neuse and Pamlico
Rivers
* Oregon Inlet North Carolina to the North Carolina/Virginia border

A Storm Surge Watch is in effect for...
* Cape Fear to Oregon Inlet North Carolina

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

A Tropical Storm Warning is in effect for...
* Edisto Beach South Carolina to South Santee River South Carolina
* North of Surf City North Carolina to Stonington Maine
* Pamlico and Albemarle Sounds
* Chesapeake Bay
* Tidal Potomac River
* Delaware Bay
* Long Island and Long Island Sound
* Martha's Vineyard, Nantucket, and Block Island

A Tropical Storm Watch is in effect for...
* North of Stonington to Eastport Maine

A Storm Surge Warning means there is a danger of life-threatening
inundation, from rising water moving inland from the coastline,
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.

A Hurricane Warning means that hurricane conditions are expected
somewhere within the warning area.

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, including possible
inland watches and warnings, please monitor products issued by your
local National Weather Service forecast office.


DISCUSSION AND OUTLOOK
----------------------
At 800 PM EDT (0000 UTC), the center of Hurricane Isaias was located
by NOAA Doppler weather radars and an Air Force Reserve Hurricane
Hunter aircraft near latitude 32.8 North, longitude 79.0 West.
Isaias is moving toward the north-northeast near 16 mph (26 km/h),
and this general motion accompanied by a gradual increase in forward
speed is expected through tonight followed by a further increase in
the forward speed on Tuesday.  On the forecast track, the center of
Isaias will approach the coasts of northeastern South Carolina and
southern North Carolina within the hurricane warning area during the
next few hours.  The center will then move inland across eastern
North Carolina early Tuesday morning, move along the coast of the
mid-Atlantic states on Tuesday, and continue across the northeastern
United States Tuesday night.

Data from NOAA Doppler weather radars and the Hurricane Hunter
aircraft indicate that maximum sustained winds have increased to ear
75 mph (120 km/h) with higher gusts.  Some additional strengthening
is possible before landfall. After landfall, only gradual weakening
is anticipated after Isaias makes landfall in the Carolinas and
moves across the U.S. mid-Atlantic region tonight and Tuesday.

Hurricane-force winds extend outward up to 25 miles (40 km) from 
the center, while tropical-storm-force winds extend outward up to   
125 miles (205 km) from the center.  NOAA buoy 41004 recently 
reported sustained winds of 60 mph (96 km/h), and a Weatherflow 
station at Winyah Bay, South Carolina recently reported sustained 
winds of 61 mph (98 km/h) and a wind gust of 69 mph (111 km/h).

The minimum central pressure based on aircraft and buoy data is 988
mb (29.18 inches).  NOAA buoy 41004 recently reported a minimum
pressure of 988.9 mb (29.20 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...

South Santee River SC to Cape Fear NC...3-5 ft

Folly Beach SC to South Santee River SC...2-4 ft

Cape Fear NC to the North Carolina/Virginia border including Pamlico
Sound, Albemarle Sound, Neuse and Pamlico Rivers...2-4 ft

Savannah River to Folly Beach SC...1-3 ft

North of the North Carolina/Virginia border to Martha's Vineyard
including the Chesapeake Bay, the Tidal Potomac River, Delaware Bay,
Long Island Sound, Block Island Sound, Narragansett Bay, Buzzards
Bay, and Vineyard Sound...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 expected within the hurricane
warning area in South and North Carolina this evening and tonight,
with tropical storm conditions spreading onshore in the next few
hours.

Widespread tropical-storm conditions are expected in the
tropical storm warning area from coastal North Carolina to the
mid-Atlantic states, including portions of the Chesapeake Bay
region, tonight and Tuesday, with wind gusts to hurricane force
possible. These winds could cause tree damage and power outages.

Tropical storm conditions are expected to reach southern New
England Tuesday afternoon and northern New England Tuesday night
and early Wednesday.

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

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

Eastern New York and western New England from Connecticut to New
Hampshire: 2 to 4 inches, isolated maximum totals 6 inches.

Western and northern Maine: 1 to 3 inches.

Heavy rainfall along the East Coast, near the path of Isaias, will
result in flash and urban flooding, some of which may be significant
in the eastern Carolinas, Mid-Atlantic and Northeast through
Wednesday. Widespread minor to moderate river flooding is possible
across portions of the Carolinas and the Mid-Atlantic.
Quick-responding rivers in Northeast will also be susceptible to
minor river flooding.

TORNADOES:  A few tornadoes will be possible near northeastern South
Carolina coastal areas by early this evening, before spreading
across eastern North Carolina tonight into Tuesday morning. A couple
of tornadoes will be possible on Tuesday from eastern Virginia
northeastward into southern New England.

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.

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