453 
 WTPZ45 KNHC 051431
 TCDEP5
 
 TROPICAL STORM IVETTE DISCUSSION NUMBER  12
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP102016
 800 AM PDT FRI AUG 05 2016
 
 Ivette continues to have a ragged appearance on satellite imagery,
 and recent microwave data showed that all the deep convection is
 located to the south and southeast of the center.  Still, Dvorak CI
 numbers from TAFB and SAB, as well as the UW-CIMSS ADT, support
 maintaining an intensity of 45 kt.  Vertical shear does not appear
 very high (about 10 kt according to SHIPS guidance and UW-CIMSS),
 but it is from a westerly direction, which is not great for
 intensification.  Since sea surface temperatures remain warm, only
 modest strengthening is anticipated during the next 24 hours.  After
 that time, deep-layer westerly shear increases over 20 kt, and this
 should cause Ivette to weaken quickly.  In fact, the NHC forecast
 now calls for the cyclone to degenerate to a remnant low in about 4
 days.  This forecast is very similar to the previous one, and it
 lies close to the IVCN intensity consensus.
 
 Ivette continues to move westward (275 degrees), but its speed has
 decreased to 11 kt.  Subtropical high pressure located to the north
 of the cyclone is causing the current westward motion, but Ivette
 is approaching a break in the ridge located northeast of Hawaii.
 Therefore, the cyclone is expected to turn west-northwestward and
 slow down some more very soon, with that heading continuing through
 day 3.  Once Ivette becomes a remnant low, it should turn westward
 in the low-level trade winds.  The track guidance remains in good
 agreement on this scenario, and the updated NHC track forecast is
 very close to the TVCN multi-model consensus.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  05/1500Z 15.1N 130.8W   45 KT  50 MPH
  12H  06/0000Z 15.4N 132.2W   50 KT  60 MPH
  24H  06/1200Z 16.1N 134.0W   55 KT  65 MPH
  36H  07/0000Z 16.8N 135.8W   55 KT  65 MPH
  48H  07/1200Z 17.5N 137.4W   50 KT  60 MPH
  72H  08/1200Z 18.6N 140.5W   35 KT  40 MPH
  96H  09/1200Z 18.8N 143.8W   30 KT  35 MPH...POST-TROP/REMNT LOW
 120H  10/1200Z 18.5N 148.0W   25 KT  30 MPH...POST-TROP/REMNT LOW
 
 $$
 Forecaster Berg