546 
 WTPZ45 KNHC 042034
 TCDEP5
 
 TROPICAL STORM IVETTE DISCUSSION NUMBER   9
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP102016
 200 PM PDT THU AUG 04 2016
 
 Vertical shear over Ivette is gradually decreasing, and the
 low-level center is now embedded beneath a persistent CDO feature.
 A recent ASCAT pass indicated that maximum winds are now near 45
 kt, which is supported by an average of subjective and objective
 satellite intensity estimates.  Ivette may finally be starting the
 gradual intensification trend that has been forecast, and the
 intensity guidance indicates that strengthening should continue for
 the next 48 hours while sea surface temperatures are warm and
 vertical shear is low.  Most of the models continue to keep Ivette
 below hurricane strength, but the NHC intensity forecast still
 makes the cyclone a hurricane in 48 hours, which is supported by
 the Florida State Superensemble and the SHIPS model.  After 48
 hours, increasing shear and lower oceanic heat content should cause
 fast weakening through day 5.
 
 The ASCAT pass was useful in helping to reposition Ivette's center,
 and the initial motion estimate is now 270/12 kt.  The subtropical
 ridge to the north of the cyclone is forecast to steer Ivette
 westward for the next 24 hours.  Thereafter, a break in the ridge
 to the northeast of Hawaii should cause the cyclone to turn
 west-northwestward and decelerate.  The updated NHC track forecast
 is adjusted a little southward during the first 3 days to account
 for the refinement of the initial position.  Otherwise, it lies
 very close to the multi-model consensus in the middle of a tightly
 packed guidance envelope.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  04/2100Z 14.7N 127.3W   45 KT  50 MPH
  12H  05/0600Z 14.8N 129.1W   50 KT  60 MPH
  24H  05/1800Z 15.0N 131.2W   55 KT  65 MPH
  36H  06/0600Z 15.5N 133.0W   60 KT  70 MPH
  48H  06/1800Z 16.1N 134.7W   65 KT  75 MPH
  72H  07/1800Z 17.4N 137.8W   60 KT  70 MPH
  96H  08/1800Z 18.5N 141.0W   45 KT  50 MPH
 120H  09/1800Z 19.0N 144.0W   35 KT  40 MPH
 
 $$
 Forecaster Berg