Tropical Storm Debby Meanders Through The SE US Update One

000

WTNT34 KNHC 080231

TCPAT4

BULLETIN

Tropical Storm Debby Advisory Number  23

NWS National Hurricane Center Miami FL       AL042024

1100 PM EDT Wed Aug 07 2024

...CENTER OF DEBBY ABOUT TO CROSS THE COAST OF SOUTH CAROLINA...

...MAJOR FLOOD THREAT CONTINUES FOR PORTIONS OF THE CAROLINAS...

SUMMARY OF 1100 PM EDT...0300 UTC...INFORMATION

-----------------------------------------------

LOCATION...32.9N 79.5W

ABOUT 25 MI...40 KM ENE OF CHARLESTON SOUTH CAROLINA

ABOUT 65 MI...105 KM SSW OF MYRTLE BEACH SOUTH CAROLINA

MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H

PRESENT MOVEMENT...NNW OR 345 DEGREES AT 3 MPH...6 KM/H

MINIMUM CENTRAL PRESSURE...994 MB...29.36 INCHES

WATCHES AND WARNINGS

--------------------

CHANGES WITH THIS ADVISORY:

The Tropical Storm Warning has been discontinued south of Edisto

Beach, South Carolina.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

A Tropical Storm Warning is in effect for...

* Edisto Beach, South Carolina to Surf City, North Carolina

A Tropical Storm Watch is in effect for...

* North of Surf City, North Carolina to Beaufort Inlet, North

Carolina

A Tropical Storm Warning means that tropical storm conditions are

expected somewhere within the warning area.

A Tropical Storm Watch means that tropical storm conditions are

possible within the watch area.

Interests elsewhere along the southeastern coast of the United

States should monitor the progress of this system.

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 1100 PM EDT (0300 UTC), the center of Tropical Storm Debby was

located near latitude 32.9 North, longitude 79.5 West. Debby is

moving toward the north-northwest near 3 mph (6 km/h). This 

general motion is expected to continue through Thursday, bringing 

the center across the South Carolina coast during the next several 

hours. A faster motion toward the north and north-northeast across 

the Carolinas and the U.S. Mid-Atlantic states is expected later on 

Thursday and on Friday.

Maximum sustained winds are near 60 mph (95 km/h) with higher gusts.

Weakening is forecast to begin on Thursday after the center moves 

inland. Debby is expected to merge with a frontal boundary over the 

U.S. Mid-Atlantic states on Friday or Friday night.

Tropical-storm-force winds extend outward up to 185 miles (295 km)

mainly to the east of the center. NOAA buoy 41013 near Frying Pan 

Shoals, North Carolina, recently reported sustained winds of 38 

mph (61 km/h) and a wind gust of 45 mph (72 km/h).

The estimated minimum central pressure based on surface 

observations and Air Force Reserve Hurricane Hunter aircraft data 

is 994 mb (29.36 inches).

HAZARDS AFFECTING LAND

----------------------

Key messages for Debby can be found in the Tropical Cyclone

Discussion under AWIPS header MIATCDAT4 and WMO header WTNT44 KNHC.

WIND: Tropical storm conditions are expected to continue along the

coast of South Carolina within the tropical storm warning area

through Thursday. Tropical storm conditions are expected within the

tropical storm warning area and possible within the tropical storm

watch area in North Carolina tonight through Thursday.

STORM SURGE: The combination of storm surge and 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 to Ocracoke Inlet including the Neuse and

Pamlico Rivers...1 to 3 ft

For a complete depiction of areas at risk of storm surge inundation,

please see the National Weather Service Peak Storm Surge Graphic,

available at hurricanes.gov/graphics_at4.shtml?peakSurge.

RAINFALL: Debby is expected to produce an additional 3 to 9 inches

of rainfall with locally higher amounts, leading to maximum storm

total amounts as high as 25 inches in eastern South Carolina and 15

inches in southeast North Carolina with considerable flooding

expected across portions of eastern South Carolina and southeast

North Carolina through Friday.

An additional 1 to 2 inches of rainfall with locally higher amounts

is possible across southeast Georgia through Thursday, bringing

overall storm total amounts as high as 15 inches, which may

aggravate any ongoing flooding conditions.

From the piedmont of South Carolina northward across portions of

Virginia, 3 to 7 inches with local amounts to 10 inches, are

expected through Friday. This rainfall will likely result in areas

of considerable flash and urban flooding, with river flooding

possible.

From Maryland north through Upstate New York and Vermont, 2 to 4

inches, with local amounts to 6 inches, are expected through

Saturday morning. This will likely produce considerable flash and

urban flooding as well as river flooding.

For Long Island and the remainder of New England, 1 to 2 inches,

with local amounts to 4 inches, are expected into Saturday.

Scattered instances of flash flooding are possible.

For a complete depiction of forecast rainfall and flash flooding

associated with  Debby, please see the National Weather Service

Storm Total Rainfall Graphic, available at

hurricanes.gov/graphics_at4.shtml?rainqpf and the Flash Flood Risk

graphic at hurricanes.gov/graphics_at4.shtml?ero.

For a list of rainfall observations (and wind reports) associated

this storm, see the companion storm summary at WBCSCCNS4 with the

WMO header ACUS44 KWBC or at the following link:

www.wpc.ncep.noaa.gov/discussions/nfdscc4.html.

TORNADOES: A few tornadoes may occur over parts of eastern North 

Carolina overnight. The risk of tornadoes will shift northward on 

Thursday into central North Carolina and central Virginia.

SURF:  Large swells will continue to affect the Southeast U.S.

coast through the end of the week. These conditions are likely to

cause life-threatening surf and rip current conditions. Please

consult products from your local weather office.

NEXT ADVISORY

-------------

Next intermediate advisory at 200 AM EDT.

Next complete advisory at 500 AM EDT.

$$

Forecaster Beven

000

WTNT44 KNHC 080232

TCDAT4

Tropical Storm Debby Discussion Number  23

NWS National Hurricane Center Miami FL       AL042024

1100 PM EDT Wed Aug 07 2024

Satellite imagery and surface observations indicate that Debby has

a large central area of light and variable winds, with bands of

deep convection well removed from the center in both the northern

and southern semicircles.  The initial intensity is held at 50 kt

for this advisory, with these winds likely confined to the area of

stronger convection to the southeast of the center.  The central

pressure based on surface observations is near 994 mb.

Debby has been drifting just west of due north for the past several 

hours with an initial motion of 345/3.  This has brought the center 

near the South Carolina coast, and it is expected to move inland 

during the next few hours.  A continued slow north-northwestward 

motion is expected for the next 24 h, with the center crossing 

eastern South Carolina moving into North Carolina.  After that, the 

cyclone should recurve to the north and northeast on the east side 

of a mid-latitude trough near the Great Lakes.  The latest track 

guidance has shifted a little to the west of the previous guidance, 

and the new forecast track is also shifted a little westward.

Little change in strength is expected before the center moves 

inland.  After that, Debby is expected to weaken, with the system 

dropping below tropical-storm strength after 24 h.  As Debby 

crosses through the mid-Atlantic States, the cyclone is expected 

to merge with a frontal system and become an extratropical low by 

60 h. However, it is important to note that none of these changes 

will diminish the threat of heavy rainfall and flooding across 

portions of the Carolinas, Mid-Atlantic, and northeastern United 

States during the next few days.

Key Messages:

1. Heavy rainfall across portions of the Carolinas is expected to

persist through Thursday along with areas of considerable flooding.

Expected heavy rainfall will also result in considerable flooding

impacts across portions of the Mid-Atlantic States and Northeast

through Saturday morning.

2. Tropical storm conditions will affect portions of the South

Carolina and North Carolina coast through Thursday. Tropical storm

warnings and watches are in effect for portions of that area.

3. Coastal flooding due to storm surge is likely along portions of

the South Carolina and North Carolina coastline through Thursday.

FORECAST POSITIONS AND MAX WINDS

INIT  08/0300Z 32.9N  79.5W   50 KT  60 MPH

 12H  08/1200Z 33.7N  79.8W   45 KT  50 MPH...INLAND

 24H  09/0000Z 35.3N  80.0W   35 KT  40 MPH...INLAND

 36H  09/1200Z 38.1N  79.0W   30 KT  35 MPH...INLAND

 48H  10/0000Z 42.1N  75.6W   30 KT  35 MPH...INLAND

 60H  10/1200Z 46.3N  70.5W   30 KT  35 MPH...POST-TROP/EXTRATROP

 72H  11/0000Z 49.0N  64.0W   30 KT  35 MPH...POST-TROP/EXTRATROP

 96H  12/0000Z...DISSIPATED

$$

Forecaster Beven