681 
 WTPA41 PHFO 092101
 TCDCP1
  
 Hurricane Hector Discussion Number  38
 NWS Central Pacific Hurricane Center Honolulu HI   EP102018
 1100 AM HST Thu Aug 09 2018
 
 Hurricane Hector has continued westward, 275/14 kt, well south of
 the main Hawaiian Islands and has maintained a well-defined eye over
 the past several hours. In the satellite imagery the system is a
 bit asymmetric with the upper level outflow better in the
 northeastern semicircle and slightly restricted on the southwestern
 side. Subjective Dvorak intensity estimates came in at 5.5/102 kt
 from PHFO, SAB, and JTWC. CIMSS ADT was 5.7/107 kt at 1800 UTC.
 Based on a blend of these values, the current intensity for this
 package is held at 105 kt.
 
 Hector has been moving westward to the south of a solid mid-level
 ridge. The ridge is forecast to weaken as a low pressure system cuts
 off near the Dateline over the next couple of days. This should
 result in a gradual turn toward the west-northwest over the next
 day or so, followed by a more northwestward track. The latest
 objective aids are in good agreement with this scenario but are a
 bit north of the previous package. Thus, the forecast has been
 adjusted north accordingly and is close to the dynamical model
 consensus. 
 
 In the near term, there do not appear to be any environmental
 factors that will result in significant intensity changes. The SSTs
 along the track are expected to be in the 27C to 28C range and
 vertical shear should remain weak over the next couple of days.
 SHIPS guidance indicates that shear should increase after 48 hours.
 Beyond day 3, the adjustment of the track forecast north of the
 previous track takes Hector across the SST gradient into cooler
 waters. Thus, the intensity forecast shows a little more aggressive
 weakening than the previous forecast with Hector weakening to a
 tropical storm on day 5. This trend is consistent with ICON. Note
 that HWRF and HMON have been the best intensity aids so far and
 show a more aggressive weakening than the official forecast,
 especially after 48 hours.
 
 A Tropical Storm Watch remains in effect for Johnston Island. If the
 expected turn toward the west-northwest does not occur, tropical
 storm conditions are possible there starting late Friday. Elsewhere,
 interests in the Northwestern Hawaiian Islands, including Midway and
 Kure Atolls and the Papahanaumokuakea Marine National Monument west
 of Laysan Island should monitor the progress of Hector. This does
 not include the main Hawaiian Islands.
 
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  09/2100Z 16.9N 161.5W  105 KT 120 MPH
  12H  10/0600Z 17.2N 163.6W  105 KT 120 MPH
  24H  10/1800Z 17.9N 166.2W  105 KT 120 MPH
  36H  11/0600Z 18.9N 168.6W  105 KT 120 MPH
  48H  11/1800Z 20.3N 170.7W   95 KT 110 MPH
  72H  12/1800Z 23.8N 175.0W   85 KT 100 MPH
  96H  13/1800Z 27.0N 179.5E   65 KT  75 MPH
 120H  14/1800Z 31.0N 174.5E   55 KT  65 MPH
  
 $$
 Forecaster Kodama