[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT44 KNHC 051441
TCDAT4

POST-TROPICAL CYCLONE HERMINE DISCUSSION NUMBER  33
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092016
1100 AM AST MON SEP 05 2016

Hermine continues to exhibit a non-tropical cloud pattern with a
broad curved band of showers to the north of the center.
High-resolution visible images show multiple low-level swirls
rotating around the broad center of the cyclone.  An Air Force
reconnaissance plane found highest unflagged SFMR-observed surface
winds of 52 kt, and highest 850 mb flight-level winds were 69 kt,
both north of the center.  The initial intensity estimate remains 60
kt.  Although Hermine is currently over rather warm waters, the
system should be passing over cooler SSTs by early Tuesday and this
should result in a weakening trend.  The official intensity forecast
is consistent with the trend depicted by the global models.  These
models, especially the ECMWF, suggest that the system will open up
to a trough by the end of the forecast period and this is also
reflected in the official forecast.

The center is not particularly well defined, and using a mean center
position from the multiple swirls leads to a motion estimate of
030/5 kt, which is rather uncertain.  Hermine is in a weak steering
environment. A narrow mid-level ridge to the north of the cyclone
should induce a continued northwestward motion at a slow forward
speed during the next 24 hours or so.  As this ridge breaks down by
Tuesday night, the system should turn northward. Later in the
forecast period, the mid-latitude westerlies should carry Hermine
off to the east-northeast and northeast.  The track forecast has
been shifted west of the previous NHC track, but lies a little to
the east of the multi-model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT  05/1500Z 38.8N  68.8W   60 KT  70 MPH...POST-TROPICAL
 12H  06/0000Z 39.2N  69.5W   60 KT  70 MPH...POST-TROPICAL
 24H  06/1200Z 39.7N  70.5W   55 KT  65 MPH...POST-TROPICAL
 36H  07/0000Z 40.0N  70.7W   45 KT  50 MPH...POST-TROPICAL
 48H  07/1200Z 40.5N  70.5W   40 KT  45 MPH...POST-TROPICAL
 72H  08/1200Z 41.0N  69.0W   35 KT  40 MPH...POST-TROPICAL
 96H  09/1200Z 44.5N  62.0W   30 KT  35 MPH...POST-TROPICAL
120H  10/1200Z...DISSIPATED

$$
Forecaster Pasch

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