ZCZC MIATCDAT3 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM LISA DISCUSSION NUMBER 16
NWS NATIONAL HURRICANE CENTER MIAMI FL AL132016
1100 AM AST FRI SEP 23 2016
Lisa's center remains exposed to the southwest of the deep
convection due to around 40 kt of southwesterly shear as analyzed by
UW-CIMSS and the SHIPS model fields. The initial intensity remains
35 kt based on the latest Dvorak estimate from TAFB, but this could
be a little generous.
Strong shear is expected to continue for the next 24 to 36 hours.
This shear, in combination with a drying mid-level atmosphere and
marginal SSTs, should result in weakening. Lisa is forecast to
weaken to a tropical depression tonight, and become a remnant low in
24 to 36 hours, as organized deep convection is expected to decay in
the harsh environment. The remnant low of Lisa is forecast to open
up into a trough in 3 to 4 days, in agreement with the latest GFS
and ECMWF solutions.
The initial motion estimate is 315/06. Lisa should continue moving
generally northwestward around the subtropical ridge for the next 36
hours. After that time, the decaying system should recurve ahead of
a deep-layer trough moving across the northern Atlantic. The new
NHC track forecast is close to the previous one through 24 hours and
has been nudged westward at 36 and 48 hours following the latest
trend in the guidance. This forecast is close to the multi-model
consensus aid TVCN and the GEFS ensemble mean.
FORECAST POSITIONS AND MAX WINDS
INIT 23/1500Z 22.2N 36.3W 35 KT 40 MPH
12H 24/0000Z 23.1N 37.5W 30 KT 35 MPH
24H 24/1200Z 24.2N 39.5W 30 KT 35 MPH
36H 25/0000Z 25.4N 41.3W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 25/1200Z 27.4N 42.3W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 26/1200Z 31.5N 40.5W 25 KT 30 MPH...POST-TROP/REMNT LOW