000
WTNT44 KNHC 161459 CCA
TCDAT4

Tropical Storm Lee Discussion Number   7...Corrected
NWS National Hurricane Center Miami FL       AL142017
1100 AM AST Sat Sep 16 2017

Corrected to include missing word in intensity discussion

Deep convection has increased in intensity and coverage since this
time yesterday, and a recent partial ASCAT pass from around 1100
UTC indicated that the system is now producing tropical-storm-force
winds at least to the east of its center.  Based on these data, the
depression is upgraded to Tropical Storm Lee with maximum winds of
35 kt.  Lee has been able to strengthen a little despite about 15
kt of north-northwesterly shear.  The cyclone appears to be located
in a sweet spot of relatively low shear, with much stronger upper-
level westerly winds located not too far to the north, and it may be
able to thread the needle of lower shear for another 36 hours or so.
After that time, the westerlies drop southward, and Lee will likely
be hammered by 30 kt of westerly shear by 48 hours.  With all that
in mind, Lee is forecast to strengthen only slightly over the next
day or so, with weakening expected to begin by day 3.  The NHC
intensity forecast is close to the intensity consensus and HCCA, and
Lee may ultimately degenerate into a remnant low by day 5.

Lee's initial motion is estimated to be 265/10 kt.  The storm is
located to the south of a weak mid-level ridge, and it is expected
to move generally westward or west-northwestward for the entire
forecast period.  Although some of the track models are showing a
more pronounced poleward motion, Lee's relatively low intensity and
eventual weakening will likely keep it steered by lower-level flow.
As a result, the NHC track forecast is near the southern edge of
the guidance envelope, although not quite as far south as the ECMWF
model.  This forecast is not too different from the previous one.

FORECAST POSITIONS AND MAX WINDS

INIT  16/1500Z 12.5N  33.1W   35 KT  40 MPH
 12H  17/0000Z 12.4N  34.1W   40 KT  45 MPH
 24H  17/1200Z 12.5N  35.3W   40 KT  45 MPH
 36H  18/0000Z 12.9N  36.7W   40 KT  45 MPH
 48H  18/1200Z 13.6N  38.4W   40 KT  45 MPH
 72H  19/1200Z 15.6N  42.3W   35 KT  40 MPH
 96H  20/1200Z 17.0N  46.0W   30 KT  35 MPH
120H  21/1200Z 18.0N  49.5W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Berg