410 
 WTPZ44 KNHC 010833
 TCDEP4
 
 HURRICANE GUILLERMO DISCUSSION NUMBER  10
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092015
 200 AM PDT SAT AUG 01 2015
 
 Guillermo's cloud pattern has changed little in organization over
 the past several hours.  Convective banding features are not as
 well defined as they were 24 hours ago, and the CDO lacks a circular
 shape.  Dvorak T-numbers remain unchanged from the previous
 advisory package, so the intensity estimate is held at 90 kt.
 Upper-level outflow has become restricted to the northwest of the
 cyclone.  The oceanic and atmospheric environment is not likely to
 become more conducive for strengthening over the next couple of
 days, and the numerical intensity guidance generally shows a
 gradual weakening trend.  Near the end of the forecast period,
 global models indicate a significant increase in vertical shear
 associated with strong upper-tropospheric westerlies near the
 Hawaiian Islands.  The official forecast is near or slightly above
 the intensity model consensus and shows, as in the previous
 advisory, weakening to tropical storm status in 96 hours.
 
 Based on geostationary and microwave center fixes, in particular an
 earlier SSMI/S pass from 0424Z, the motion has slowed somewhat and
 is now estimated to be about 285/14 kt.  Guillermo is approaching a
 weakness in the zonally-oriented mid-level ridge to its north, and
 this should result in further deceleration over the next couple of
 days.  In 3-5 days, the steering currents become less well defined
 in the global models and there is a fair amount of spread in the
 dynamical track predictions.  The ECMWF model has been doing a bit
 of a flip-flop in its last few runs, and it has shifted back the
 south after shifting northward in the previous run.  The official
 forecast is held very close to the previous NHC track and is close
 to the latest track model consensus, TVCN, which combines not only
 the GFS and ECMWF solutions but also the HWRF, GFDL, and U.K. Met.
 Office model forecasts.
 
 Due to uncertainties in longer-range track predictions, it is
 important for users not to focus on the exact track forecasts at 96
 and 120 hours.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  01/0900Z 13.4N 137.4W   90 KT 105 MPH
  12H  01/1800Z 13.9N 139.6W   90 KT 105 MPH
  24H  02/0600Z 14.5N 142.0W   90 KT 105 MPH
  36H  02/1800Z 15.1N 144.0W   85 KT 100 MPH
  48H  03/0600Z 15.8N 145.4W   75 KT  85 MPH
  72H  04/0600Z 17.3N 148.0W   65 KT  75 MPH
  96H  05/0600Z 19.0N 151.0W   60 KT  70 MPH
 120H  06/0600Z 20.5N 154.0W   50 KT  60 MPH
 
 $$
 Forecaster Pasch