[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT44 KNHC 050257
TCDAT4

POST-TROPICAL CYCLONE HERMINE DISCUSSION NUMBER  31
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092016
1100 PM AST SUN SEP 04 2016

Hermine remains a post-tropical cyclone with all of the deep
convection located well north of the center.  Deep convection
associated with the system has increased over the northern and
northwestern portions of the circulation this evening, but it does
not appear that there has been an increase in wind speed.  The
initial intensity is set at 60 kt, which is in agreement with
recent SFMR wind observations from an Air Force Reserve
reconnaissance aircraft.  The aircraft has also recently reported a
minimum pressure of 997 mb.  Little change in strength is expected
overnight, but the global models indicate that weakening should
begin by late Monday.  Continued weakening is expected during the
remainder of the forecast period, and both the ECMWF and GFS
dissipate the cyclone by day 5, and this is now reflected in the
official forecast.

Hermine has continued to move eastward since the previous advisory,
but the most recent fix from the aircraft suggests that the eastward
motion may be ending.  A shortwave trough moving off the coast
of North Carolina should cause Hermine to turn northwestward later
tonight, then a slow north-northwestward or northward motion should
continue into Tuesday.  After that time, the cyclone should turn
northeastward around the western portion of the mid- to upper-level
ridge over the west-central Atlantic.  The NHC forecast track is
once again a blend of the latest GFS and ECMWF models, but has been
adjusted slightly eastward based on the more eastward initial
position.

The initial wind radii have been adjusted based on data from the
reconnaissance aircraft and a recent ASCAT overpass.


FORECAST POSITIONS AND MAX WINDS

INIT  05/0300Z 37.2N  68.5W   60 KT  70 MPH...POST-TROPICAL
 12H  05/1200Z 37.9N  68.8W   60 KT  70 MPH...POST-TROPICAL
 24H  06/0000Z 38.7N  69.7W   55 KT  65 MPH...POST-TROPICAL
 36H  06/1200Z 39.2N  70.0W   45 KT  50 MPH...POST-TROPICAL
 48H  07/0000Z 39.8N  69.2W   40 KT  45 MPH...POST-TROPICAL
 72H  08/0000Z 40.6N  67.2W   35 KT  40 MPH...POST-TROPICAL
 96H  09/0000Z 42.5N  63.0W   30 KT  35 MPH...POST-TROPICAL
120H  10/0000Z...DISSIPATED

$$
Forecaster Brown

This weather bulletin was brought to you by:
www.nashvilleweather.net