067 
 WTNT41 KNHC 281451
 TCDAT1
 
 TROPICAL DEPRESSION ELEVEN DISCUSSION NUMBER   3
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
 1100 AM AST MON SEP 28 2015
 
 Satellite imagery indicates that the depression's overall cloud
 pattern has become better organized since yesterday despite
 persistent north- northwesterly shear of about 20 kt.  The exposed
 low-level center is located near the northwestern tip of a curved
 band over the southeastern quadrant of the circulation. However,
 satellite data indicate that the low- to mid-level centers have
 recently become more separated.  Dvorak intensity estimates are a
 consensus T2.0/30 kt from TAFB and SAB, so the initial intensity is
 held at 30 kt.
 
 Smoothing fixes over the last 12 hours yields an initial motion of
 300/04, a little faster than before.  The depression is embedded in
 low- to mid-level southeasterly flow around a ridge to its
 northeast, with northwesterly flow aloft.  This synoptic pattern
 should only favor a slow northwestward motion for the next couple of
 days.  After 48 hours, the cyclone should reach the western end of
 the low- to mid-level subtropical ridge and begin to respond to the
 southerly and southwesterly flow ahead of a baroclinic trough
 nearing the U.S. east coast.  This change to the steering should
 result in a gradual northward turn with increasing forward speed.
 The new track forecast is a little left of the previous one at 48
 hours and a little faster, close to a blend of the GFS and ECWMF
 model solutions.
 
 GFS- and ECMWF-based SHIPS model output indicates a continuation of
 moderately strong north-northwesterly shear over the cyclone for the
 next day or so.  Even though other large-scale factors are generally
 conducive for intensification during this time, shear of this
 magnitude suggests that only slow intensification is possible. While
 the shear should decrease some by 36 hours, other environmental
 factors are not forecast to be as conducive and little further
 strengthening is indicated.  Large-scale models depict the cyclone
 merging with a frontal zone offshore of the Mid-Atlantic or New
 England coasts by 96 hours, and the system is therefore shown to be
 post-tropical at that time.  An alternate lower probability scenario
 is that the cyclone could race ahead of the frontal boundary and
 retain its tropical characteristics for a bit longer. The new
 intensity forecast is above the previous one through 24 hours and
 near the multi-model consensus but below the statistical-dynamical
 guidance after that time due to more reliance on the global models
 which show little further intensification.
 
 
 
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  28/1500Z 27.8N  69.6W   30 KT  35 MPH
  12H  29/0000Z 28.1N  70.0W   40 KT  45 MPH
  24H  29/1200Z 28.5N  70.6W   40 KT  45 MPH
  36H  30/0000Z 29.1N  71.4W   40 KT  45 MPH
  48H  30/1200Z 29.6N  72.0W   40 KT  45 MPH
  72H  01/1200Z 32.0N  72.9W   35 KT  40 MPH
  96H  02/1200Z 37.7N  72.9W   35 KT  40 MPH...POST-TROPICAL
 120H  03/1200Z...DISSIPATED
 
 $$
 Forecaster Kimberlain