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Tropical Storm Terry Discussion Number  15
NWS National Hurricane Center Miami FL       EP182021
900 PM CST Sun Nov 07 2021
 
Terry remains a very low latitude tropical storm.  The system has
generally changed little during the past several hours, with the
cloud pattern consisting of a ragged central dense overcast feature
and broken curved bands that are most organized in the northwestern
quadrant.  The latest Dvorak estimates from TAFB, SAB, and CIMSS at
the University of Wisconsin range from 35 to 50 kt, and the initial
intensity is nudged up to 40 kt based on that data.
 
The track forecast reasoning is unchanged.  The storm is moving
west-northwestward at 12 kt, and it is expected to move westward to
west-northwestward through Monday. Thereafter, a due westward motion
is expected as Terry moves on the south side of a strong low- to
mid-level ridge.  The models all show a similar theme, but there is
some cross- and along-track spread.  The new track forecast is a
touch north of the previous one to come into better agreement with
the latest consensus aids.
 
Now that Terry has pulled away from the Gulf of Tehuantepec, where
dry and stable air was entraining into the system, some slight
additional strengthening is possible in the short term as the large
scale conditions remain generally favorable.  However, in a couple
of days, increasing southerly shear will likely end the opportunity
for strengthening and cause a gradual decay.  The GFS and ECMWF both
show Terry's convection losing organization around the middle of the
week and those models also show the system dissipating within the
ITCZ in 4 or 5 days.   There is a large spread in the intensity
models, but given the expected environmental conditions, the NHC
intensity forecast continues to lie near the low end of the
guidance.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  08/0300Z  9.0N 103.8W   40 KT  45 MPH
 12H  08/1200Z  9.5N 105.8W   45 KT  50 MPH
 24H  09/0000Z 10.0N 108.1W   45 KT  50 MPH
 36H  09/1200Z 10.4N 110.7W   40 KT  45 MPH
 48H  10/0000Z 10.6N 113.2W   35 KT  40 MPH
 60H  10/1200Z 10.6N 115.9W   35 KT  40 MPH
 72H  11/0000Z 10.7N 118.4W   30 KT  35 MPH
 96H  12/0000Z 10.5N 124.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  13/0000Z...DISSIPATED
 
$$
Forecaster Cangialosi
 
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