Official Discussion issued by the National Hurricane Center

Vicky (AL212020) DATA RELEASED: 9/15/2020 2:00:00 AM UTC

Copy of official data

Tropical Storm Vicky Discussion Number   4
NWS National Hurricane Center Miami FL       AL212020
200 AM CVT Tue Sep 15 2020

Vicky continues to be highly sheared due to strong upper- 
tropospheric flow associated with a nearby trough, and its 
associated deep convection is confined to a small cluster to the 
northeast of the center.  An ASCAT overpass from a few hours ago 
showed an area of winds to just over 40 kt over the northern 
semicircle and, based on sampling limitations, the current intensity 
has been adjusted to 45 kt.  The storm is not likely to maintain its 
intensity, since the dynamical guidance indicates that the shear 
over the cyclone will become even stronger during the next day or 
so.  Therefore steady weakening is anticipated, and Vicky is likely 
to become a remnant low in about 36 hours.  The official intensity 
forecast is near or slightly below the latest model consensus.

Center fixes give a slow northwestward motion, or 315/6 kt.  A 
narrow and weak low- to mid-level ridge to the north of Vicky 
should result in a northwestward to west-northwestward motion 
into early Wednesday.  Thereafter, when the system will have 
probably have lost most of its deep convection, the shallow cyclone 
is likely to move mainly westward following the low-level 
environmental winds.  The official track forecast is close to 
previous one and about in the middle of the guidance suite.

FORECAST POSITIONS AND MAX WINDS

INIT  15/0300Z 19.5N  29.9W   45 KT  50 MPH
12H  15/1200Z 20.5N  31.0W   40 KT  45 MPH
24H  16/0000Z 21.4N  32.7W   35 KT  40 MPH
36H  16/1200Z 22.0N  34.8W   30 KT  35 MPH...POST-TROP/REMNT LOW
48H  17/0000Z 22.3N  37.0W   30 KT  35 MPH...POST-TROP/REMNT LOW
60H  17/1200Z 22.5N  39.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
72H  18/0000Z 22.5N  41.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
96H  19/0000Z 22.5N  44.5W   20 KT  25 MPH...POST-TROP/REMNT LOW
120H  20/0000Z...DISSIPATED

$$
Forecaster Pasch