217 
 WTPZ42 KNHC 052039
 TCDEP2
 
 Hurricane Olivia Discussion Number  20
 NWS National Hurricane Center Miami FL       EP172018
 200 PM PDT Wed Sep 05 2018
 
 While satellite imagery shows that the erosion of the eyewall
 convection is less than seen 6 h ago, the various satellite
 intensity estimates indicate that Olivia continues to slowly
 weaken.  Based on a blend of these estimates, the initial intensity
 is reduced to 85 kt.  Recent satellite data indicate that the wind
 and wave fields associated with Olivia are larger than previously
 analyzed, and they have been revised for this advisory.
 
 Ongoing moderate easterly shear over Olivia should diminish during
 the next 12 h or so.  After that, the major influences on the
 intensity should be gradually decreasing sea surface temperatures
 along the forecast track and entrainment of air that gets
 progressively drier through the forecast period.  The intensity
 guidance is still in good agreement that Olivia should weaken
 through the forecast period, and the new intensity forecast again
 follows this trend.  Overall, the intensity forecast is in best
 agreement with the SHIPS model and the IVCN intensity consensus.
 
 The initial motion is now 285/11.  A large deep-layer ridge seen in
 water vapor imagery to the north of Olivia should steer the
 hurricane generally west-northwestward for the next 2-3 days.
 After that time, the ridge builds westward to the northeast and
 north of the Hawaiian Islands, and this should cause Olivia to
 turn westward.  The track guidance remains in good agreement with
 this scenario, although the UKMET and the UKMET ensemble mean are
 still showing a motion to the north of the other models.  The new
 forecast track is similar to the previous track, and it generally
 lies between the track consensus model TVCN and the HFIP corrected
 consensus model.
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  05/2100Z 17.3N 123.5W   85 KT 100 MPH
  12H  06/0600Z 17.9N 125.3W   80 KT  90 MPH
  24H  06/1800Z 18.6N 127.9W   80 KT  90 MPH
  36H  07/0600Z 19.5N 130.6W   75 KT  85 MPH
  48H  07/1800Z 20.4N 133.3W   70 KT  80 MPH
  72H  08/1800Z 21.5N 138.5W   60 KT  70 MPH
  96H  09/1800Z 22.0N 143.5W   55 KT  65 MPH
 120H  10/1800Z 22.5N 148.0W   55 KT  65 MPH
 
 $$
 Forecaster Beven