Atlantic Basin Tropical Cyclones

Tropical Storm Victor Forecast Discussion


118 
WTNT45 KNHC 020842
TCDAT5

Tropical Storm Victor Discussion Number  12
NWS National Hurricane Center Miami FL       AL202021
500 AM AST Sat Oct 02 2021

Victor's satellite appearance has continued to degrade this morning 
with the closest convection now located more than 150 nmi northeast 
of the fully exposed low-level circulation center. Thus, Victor no 
longer technically meets the convective criterion of a tropical 
cyclone. However, tropical cyclone status is being maintained for 
this advisory out of continuity with the previous advisory and just 
in case a burst of deep convection redevelops later today near the 
still-well-defined low-level circulation center. Victor's intensity 
has been lowered to 45 kt based on a subjective Dvorak current 
intensity estimate of CI3.0/45 kt from TAFB, and the typical decay 
rate and spin down of a non-convective vortex over open water.

The motion estimate remains west-northwestward, or 300/11 kt. Victor 
is forecast to move west-northwestward to northwestward around the 
southwestern periphery of a deep-layer subtropical ridge for the 
next 72-96 hours or until dissipation occurs.  The new NHC forecast 
track is similar to the previous advisory track, and lies close to 
the tightly packed simple- and corrected-consensus track models.

Deep-layer south-southwesterly vertical wind shear of around 20 kt 
and entrainment of dry mid-level air have taken their toll on 
Victor. These unfavorable environmental parameters are expected to 
worsen, resulting in continued weakening throughout the forecast 
period. Therefore, Victor is forecast to become a tropical 
depression by Sunday, degenerate into a remnant low by Monday, and 
dissipate by Wednesday. However, the current weakening trend will 
be hastened if organized convection does not return within the next 
12 hours. The new official intensity forecast is a little lower 
than the previous advisory, and is also lower than most of the 
intensity guidance due to Victor's aforementioned severely degraded 
convective pattern.


FORECAST POSITIONS AND MAX WINDS

INIT  02/0900Z 12.8N  36.3W   45 KT  50 MPH
 12H  02/1800Z 13.8N  37.7W   35 KT  40 MPH
 24H  03/0600Z 15.5N  39.6W   30 KT  35 MPH
 36H  03/1800Z 17.6N  41.8W   25 KT  30 MPH
 48H  04/0600Z 19.8N  43.5W   20 KT  25 MPH...POST-TROP/REMNT LOW
 60H  04/1800Z 21.7N  45.4W   20 KT  25 MPH...POST-TROP/REMNT LOW
 72H  05/0600Z 23.1N  47.4W   20 KT  25 MPH...POST-TROP/REMNT LOW
 96H  06/0600Z...DISSIPATED

$$
Forecaster Stewart




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