####018002008####
WTNT44 KNHC 150231

TCDAT4

 

Tropical Depression Sean Discussion Number  17

NWS National Hurricane Center Miami FL       AL192023

1100 PM AST Sat Oct 14 2023

 

Deep convection continues to burst near Sean's center, and as a 

result, Dvorak estimates from TAFB and SAB remain T2.0/30 kt.  In 

addition, a recent ASCAT-B pass showed winds a little over 25 kt, 

and all these estimates support maintaining Sean as a 30-kt 

tropical depression.  With relatively low vertical shear, warm sea 

surface temperatures of 28-29 degrees Celsius, and an unstable 

atmosphere, the environment is just conducive enough for additional 

bursts of convection.  The biggest limiting factor is a lack of 

mid-level moisture, with relative humidities running about 50 

percent.  Consequently, the convection is likely to become less 

persistent and less organized, and global models indicate that 

Sean's small circulation should open up into a trough over the next 

day or two.  The NHC forecast shows Sean degenerating into a remnant 

low in 24 hours and then dissipating by 48 hours, but it's also 

possible that the system remains a tropical depression right up 

until it opens up into a trough.



Sean continues to move northwestward, or 305/7 kt.  As it becomes a 

weaker system, the depression is expected to become increasingly 

steered by lower-level ridging.  As a result, Sean is expected to 

turn west-northwestward overnight and then westward by early Monday, 

just before or as it degenerates into a trough.  The NHC track 

forecast is very close to the previous prediction and the latest 

TVCA multi-model consensus.

 

 

FORECAST POSITIONS AND MAX WINDS

 

INIT  15/0300Z 16.9N  45.5W   30 KT  35 MPH

 12H  15/1200Z 17.3N  46.6W   30 KT  35 MPH

 24H  16/0000Z 17.7N  48.4W   25 KT  30 MPH...POST-TROP/REMNT LOW

 36H  16/1200Z 18.1N  50.5W   25 KT  30 MPH...POST-TROP/REMNT LOW

 48H  17/0000Z...DISSIPATED

 

$$

Forecaster Berg