737 
 WTNT41 KNHC 021453
 TCDAT1
 
 HURRICANE JOAQUIN DISCUSSION NUMBER  19
 NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
 1100 AM EDT FRI OCT 02 2015
 
 An Air Force Reserve Hurricane Hunter aircraft has reported 700-mb
 flight-level winds of 124 kt in the southeastern eyewall, along
 with an eyewall dropsonde that supports surface winds of 110-115
 kt.  Based on these data, the intensity remains 115 kt.  The latest
 central pressure indicated by the aircraft data is 939 mb.  While
 the hurricane continues to produce cloud tops of -80C in the
 eyewall, the eye is ragged and poorly defined in satellite imagery.
 
 Joaquin has turned northward during the past few hours and the
 initial motion is now 360/3.  Water vapor imagery shows a mid- to
 upper-level ridge to the north and northeast of the hurricane,
 while a deep-layer trough and associated surface front are located
 over the southeastern United States.  This system is forecast to
 move slowly eastward with a non-tropical low forming along the
 front during the next couple of days.  These developments should
 steer Joaquin northward to northeastward during the next 12 hours
 or so, followed by a faster motion toward the northeast.  The GFS,
 UKMET, and ECMWF are now in better agreement that Joaquin will move
 generally northeastward through 48 hours, followed by a more
 northward turn between 48 and 72 hours.  This is then followed
 by movement into the westerlies and acceleration toward the east-
 northeast after 72 hours.  The new forecast track is adjusted to
 the east of the previous track after 24 hours, and it lies between
 the previous track and the model consensus.  Some additional
 eastward adjustments to the track may occur on the next advisory
 based on the 1200 UTC model runs.
 
 Joaquin is forecast to remain in an environment of light vertical
 wind shear for another 24 hours or so, and during this time some
 fluctuations in intensity are possible due to eyewall replacement
 cycles.  After 24 hours, the shear is forecast to increase, which
 should start a steady weakening.  Extratropical transition is
 expected to begin after 96 hours, but the dynamical models suggest
 it may not be complete before 120 hours.  Overall, the new
 intensity forecast is an update of the previous advisory and lies
 near the upper edge of the intensity guidance.
 
 
 KEY MESSAGES:
 
 1.  Hurricane conditions over portions of the Bahamas are likely to
 continue into this evening.
 
 2.  Swells from a hurricane moving even far offshore of the U.S.
 east coast can still cause life-threatening surf and rip-current
 conditions.  Please see products from your local National Weather
 Service forecast office.  For information on the heavy rains
 occurring along the U.S. Atlantic states that are mostly unrelated
 to Hurricane Joaquin, please see products from the NWS Weather
 Prediction Center and your local forecast office.
 
 3. A Tropical Storm or Hurricane Watch could be required for
 Bermuda this afternoon.
 
 
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  02/1500Z 23.5N  74.8W  115 KT 130 MPH
  12H  03/0000Z 24.4N  74.4W  115 KT 130 MPH
  24H  03/1200Z 26.1N  73.0W  115 KT 130 MPH
  36H  04/0000Z 28.2N  71.2W  105 KT 120 MPH
  48H  04/1200Z 30.6N  69.6W   95 KT 110 MPH
  72H  05/1200Z 35.5N  67.5W   80 KT  90 MPH
  96H  06/1200Z 39.5N  63.0W   65 KT  75 MPH
 120H  07/1200Z 43.5N  49.0W   55 KT  65 MPH
 
 $$
 Forecaster Beven