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Tropical Depression LEE


Tropical Depression Lee Discussion Number  11
NWS National Hurricane Center Miami FL       AL142017
1100 AM AST Sun Sep 17 2017

An 1144 UTC ASCAT pass indicated that Lee is no longer producing
tropical-storm-force winds.  In addition, deep convection is
fizzling, and there are only a few convective elements remaining in
a band to the south of the center.  Lee is downgraded to a tropical
depression with 30-kt winds, and even that could be generous given
what the ASCAT data is showing.  Since the cyclone is already
struggling in its current environment, it probably won't do much
better going forward since vertical shear is expected to increase
to 30 kt in about 24 hours.  Therefore, gradual weakening is
expected, and Lee could degenerate into a remnant low by 48 hours,
if not sooner.  The GFS and ECMWF both dissipate the low in 3 to 4
days, so the new NHC forecast now shows that occurring by day 4.

Lee is moving westward, or 280/7 kt.  Even though the ridge to the
north of the cyclone is not very strong, Lee's weak nature should
cause it to be steered generally westward or west-northwestward for
the next 3 days before it dissipates.  The NHC track forecast
remains just south of the various consensus aids, and it is not too
different from the previous forecast.


INIT  17/1500Z 13.0N  36.7W   30 KT  35 MPH
 12H  18/0000Z 13.2N  37.8W   30 KT  35 MPH
 24H  18/1200Z 13.8N  39.5W   30 KT  35 MPH
 36H  19/0000Z 14.7N  41.2W   25 KT  30 MPH
 48H  19/1200Z 15.7N  42.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  20/1200Z 17.5N  45.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  21/1200Z...DISSIPATED

Forecaster Berg