490 
 WTPZ41 KNHC 171437
 TCDEP1
 
 TROPICAL STORM ESTELLE DISCUSSION NUMBER   9
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP062016
 900 AM MDT SUN JUL 17 2016
 
 A large burst of deep convection developed over the center of
 Estelle overnight and continues this morning.  A timely SSMIS
 microwave overpass was very helpful in examining the structure and
 center location of the tropical cyclone.  The microwave data
 revealed a well-defined low-level ring located near the northwestern
 edge of the primary convective band, but there was no evidence of a
 mid-level eye.  The latest Dvorak T-numbers from SAB and TAFB
 are 3.5 and 4.0, respectively, and UW/CIMSS ADT estimates have
 risen to T3.5/55 kt.  These data support an initial wind speed
 of 55 kt for this advisory.
 
 The initial motion estimate is 285/7 kt. A strong subtropical ridge
 to the north of Estelle should keep the tropical cyclone moving on
 a westward to west-northwestward heading during the next several
 days. Near the end of the forecast period, Estelle will be
 approaching the western portion of the ridge, which should allow the
 tropical cyclone to gain more latitude.  The guidance is more
 tightly clustered today than it was 24 hours ago, so there is
 increased confidence in the track forecast.  The new NHC track is
 near the Florida State Superensemble and an average of the GFS/ECMWF
 models.
 
 There appears to be some north or northwesterly shear still
 affecting Estelle, but the shear is not expected to be strong
 enough to prevent intensification during the next day or so. After
 that time, the shear is forecast to relax, and Estelle is forecast
 to strengthen at a faster rate on Monday.  The track of the tropical
 cyclone brings it over cooler waters in 2 to 3 days, which should
 start the weakening process, and it should continue throughout the
 remainder of the forecast period.  The updated intensity forecast is
 similar to the previous advisory, and is closest to the Florida
 State Superensemble and the intensity consensus IVCN.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  17/1500Z 16.3N 111.8W   55 KT  65 MPH
  12H  18/0000Z 16.6N 112.9W   65 KT  75 MPH
  24H  18/1200Z 17.2N 114.6W   70 KT  80 MPH
  36H  19/0000Z 17.6N 116.3W   80 KT  90 MPH
  48H  19/1200Z 17.9N 118.1W   85 KT 100 MPH
  72H  20/1200Z 18.2N 122.2W   80 KT  90 MPH
  96H  21/1200Z 19.0N 127.0W   65 KT  75 MPH
 120H  22/1200Z 20.8N 132.5W   45 KT  50 MPH
 
 $$
 Forecaster Brown