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WTNT41 KNHC 221453

TCDAT1

 

Potential Tropical Cyclone Sixteen Discussion Number   5

NWS National Hurricane Center Miami FL       AL162023

1100 AM EDT Fri Sep 22 2023

 

Surface observations indicate the low pressure system off the 

southeast U.S. coast is deepening this morning. Recent pressure and 

wind data from NOAA buoy 41002 suggest the pressure has fallen to 

around 996 mb. While surface analyses indicate there is still a 

front in close proximity to the low, deep convection has become more 

concentrated to the north of the center. In fact, GOES-16 1-min 

visible imagery suggests the low-level center is re-forming closer 

to the convection. The broad wind field is asymmetric, with the 

strongest observed winds occurring to the north and west of the 

frontal feature. A NOAA Saildrone sampling the system reported a 

sustained wind of 40 kt and a gust around 50 kt earlier this 

morning. Based on the available observations, the initial intensity 

is held at 45 kt. An Air Force Reserve Hurricane Hunter aircraft is 

scheduled to investigate the system this afternoon.



The initial motion of the cyclone is just west of due north (350/10 

kt). The system is forecast to move north-northwestward to northward 

through Saturday along the west side of a subtropical ridge over the 

western and central Atlantic. This motion will take the center of 

the cyclone inland over eastern North Carolina on Saturday morning 

and over the Mid-Atlantic region Saturday night and Sunday. The 

track guidance is in good agreement for this forecast. Based on the 

slight northward adjustment to the initial position, the updated NHC 

forecast is slightly faster than the previous one, showing the 

cyclone center just inland in 24 h.



Based on recent satellite and observational trends, the cyclone 

appears likely to strengthen during the next 12 h over the warm Gulf 

Stream waters. The more organized convective structure should also 

facilitate its transition to a tropical storm during the next 6-12 h 

as it starts to become separated from its frontal features and 

develops a smaller inner core. The near-term intensity forecast has 

been bumped up slightly (55 kt) before the system moves inland early 

Saturday. After landfall, the system is expected to weaken due to 

the negative influences of land interaction, drier air, and strong 

upper-level winds. This forecast shows extratropical transition by 

48 h with dissipation by 72 h, in good agreement with the GFS and 

ECMWF models. 



 

Key Messages:

 

1. Tropical storm conditions are expected along portions of the 

southeastern and mid-Atlantic U.S. coasts within the Tropical Storm 

Warning area today into Saturday night.

 

2. There is a danger of life-threatening storm surge inundation

over portions of eastern North Carolina and southeastern Virginia,

including Pamlico and Albemarle Sounds, the Neuse and Pamlico 

Rivers, the lower James River, and the lower Chesapeake Bay, where 

Storm Surge Warnings are in place.  Residents in these areas should 

follow advice given by local officials.

 

3. Heavy rainfall from this system could produce flash, urban, and 

small stream flooding impacts across portions of the Mid-Atlantic 

states from North Carolina to New Jersey through Sunday.

 

4. Swells generated by this system will affect much of the U.S.

east coast through the weekend, likely causing life-threatening

surf and rip currents.

 

 

FORECAST POSITIONS AND MAX WINDS

 

INIT  22/1500Z 32.3N  75.6W   45 KT  50 MPH...POTENTIAL TROP CYCLONE

 12H  23/0000Z 33.2N  76.3W   55 KT  65 MPH...TROPICAL CYCLONE

 24H  23/1200Z 34.9N  76.8W   50 KT  60 MPH...INLAND

 36H  24/0000Z 36.8N  77.0W   40 KT  45 MPH...INLAND

 48H  24/1200Z 38.3N  77.0W   30 KT  35 MPH...POST-TROP/EXTRATROP

 60H  25/0000Z 39.3N  76.5W   25 KT  30 MPH...POST-TROP/EXTRATROP

 72H  25/1200Z...DISSIPATED

 

$$

Forecaster Reinhart