165 
 WTNT45 KNHC 152031
 TCDAT5
 
 Tropical Storm Joyce Discussion Number  13
 NWS National Hurricane Center Miami FL       AL102018
 500 PM AST Sat Sep 15 2018
 
 The circulation of Joyce is elongated this afternoon, with the
 center partially exposed.  It has been interesting to watch deep
 convection firing in the northeastern quadrant, kicking off new
 small swirls that rotate around the mean circulation.  A blend of
 the Dvorak estimates from TAFB/SAB supports keeping the wind speed
 40 kt on this advisory.
 
 There is no change to the intensity forecast reasoning.  The
 environment is predicted to be nearly steady-state around Joyce
 through Sunday, with strong shear being offset by waters near 27C.
 Thereafter, as the hostile shear continues, the mid-level air should
 become drier near the center, and SSTs cool off below 26C.  These
 conditions should cause Joyce to slowly weaken early next week, and
 dissipate in 3 days or so.  This forecast is basically the same as
 the previous one, but it isn't out of the realm of possibility the
 cyclone could open up into a trough before that time.
 
 Joyce continues to accelerate, now moving east-northeastward at
 about 15 kt.  The storm remains embedded within the same trough as
 Tropical Storm Helene, and Joyce should move east-northeastward
 during the next day or so.  Beyond that time, as Joyce becomes a
 shallow cyclone, it is forecast to turn southeastward due to
 low-level flow around the eastern side of a building ridge over the
 central Atlantic Ocean.  The track forecast is simply an update to
 the previous one, and continues to be on the southern side of the
 guidance envelope.
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  15/2100Z 33.1N  39.6W   40 KT  45 MPH
  12H  16/0600Z 34.1N  37.2W   40 KT  45 MPH
  24H  16/1800Z 34.8N  33.8W   40 KT  45 MPH
  36H  17/0600Z 34.8N  30.5W   35 KT  40 MPH
  48H  17/1800Z 34.0N  28.0W   30 KT  35 MPH
  72H  18/1800Z 31.5N  26.5W   25 KT  30 MPH
  96H  19/1800Z...DISSIPATED
 
 $$
 Forecaster Blake