Atlantic Basin Tropical Cyclones

Subtropical Depression Teresa Forecast Discussion

WTNT44 KNHC 251445

Subtropical Depression Teresa Discussion Number   4
NWS National Hurricane Center Miami FL       AL192021
1100 AM AST Sat Sep 25 2021

Teresa has been devoid of deep convection for more than 12 hours
now.  The cloud pattern consists of a swirl of low-level clouds and
a band of showers and thunderstorms located about 250 n mi north of
the center.  This patch of convection is detached from the
low-level circulation, and it appears to be more involved with an
upper-level trough to the northeast of Teresa.  A 1210 UTC ASCAT-A
pass shows that the winds within that convection have decreased,
with several vectors in the 25 to 30 kt range.  Based on that
data, the intensity is lowered to 30 kt, making Teresa a
subtropical depression.

Teresa is unlikely to redevelop any convection near its center as
strong west-southwesterly wind shear continues over the cyclone.
This will prevent any opportunity for strengthening.  Teresa is
expected to become a remnant low later today or this evening and
dissipate on Sunday.  The global models are in good agreement with
this scenario.

Teresa has moved little during the past 12 hours, so a stationary
motion is currently indicated for this advisory.  However, a motion
toward the northeast should begin within the next few hours and
continue through dissipation as the cyclone moves in the flow ahead
of a deep-layer trough.  The track forecast was adjusted a little
to the east of the previous advisory, and is in agreement with the
model consensus.


INIT  25/1500Z 34.3N  65.0W   30 KT  35 MPH
 12H  26/0000Z 35.4N  64.4W   30 KT  35 MPH...POST-TROP/REMNT LOW
 24H  26/1200Z 37.2N  62.6W   30 KT  35 MPH...POST-TROP/REMNT LOW
 36H  27/0000Z...DISSIPATED

Forecaster Hagen/Beven

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