214 
WTNT43 KNHC 091442
TCDAT3

Tropical Storm Helene Discussion Number   9
NWS National Hurricane Center Miami FL       AL082018
1100 AM AST Sun Sep 09 2018

Helene continues to exhibit a fairly well-organized cloud pattern,
but does not yet have a well-defined inner core.  The current
intensity estimate, 55 kt, is based on a blend of subjective and
objective Dvorak estimates and is also close to the latest SATCON
value.  The tropical cyclone is expected to remain over warm waters
with low to moderate vertical wind shear for the next couple of
days.  Therefore, strengthening is likely through the early part of
this week.  Later in the period, marginal SSTs and increasing
south-southwesterly shear should induce weakening.  The official
wind speed forecast is on the high side of the numerical intensity
guidance.

Helene continues to move westward, or about 270/11 kt.  The system
should move westward to west-northwestward to the south of a
mid-level ridge over the eastern Atlantic over the next 48 hours or
so.  Thereafter, a mid-level trough is expected to create a
pronounced weakness in the ridge along 40W-45W longitude.  This
steering pattern is likely to cause Helene to turn northwestward to
north-northwestward during the latter part of the forecast period.
The official track forecast is very similar to the previous NHC
prediction and lies roughly in the middle of the numerical guidance
suite.

FORECAST POSITIONS AND MAX WINDS

INIT  09/1500Z 13.2N  25.0W   55 KT  65 MPH
 12H  10/0000Z 13.7N  27.1W   65 KT  75 MPH
 24H  10/1200Z 14.3N  30.0W   75 KT  85 MPH
 36H  11/0000Z 14.9N  32.8W   85 KT 100 MPH
 48H  11/1200Z 15.7N  35.2W   90 KT 105 MPH
 72H  12/1200Z 17.8N  38.6W   80 KT  90 MPH
 96H  13/1200Z 21.0N  41.0W   65 KT  75 MPH
120H  14/1200Z 26.0N  43.0W   55 KT  65 MPH

$$
Forecaster Pasch