207 
 WTPZ41 KNHC 302037
 TCDEP1
 
 HURRICANE ANDRES DISCUSSION NUMBER  11
 NWS NATIONAL HURRICANE CENTER MIAMI FL       EP012015
 200 PM PDT SAT MAY 30 2015
 
 Andres' cloud pattern has not changed much during the last several
 hours.  The eye of the hurricane remains evident in visible and
 infrared satellite images, but it has been occasionally obscured by
 high-level clouds.  Recent microwave data show that the western side
 of the eyewall has eroded slightly, which is likely the result of
 northwesterly shear and drier air that is wrapping into that side of
 the circulation.  The Dvorak classifications from TAFB, SAB, and the
 UW-CIMSS ADT are all 5.0/90 kt, and accordingly, the initial wind
 speed is held at that value.
 
 Andres continues on a northwestward track at about 6 kt toward a
 weakness in the subtropical ridge.  The models are in agreement
 that the hurricane should turn west-northwestward tonight or early
 Sunday when the ridge builds to the north of the cyclone. The 12Z
 GFS solution has changed considerably from the previous cycle, and
 now shows Andres stalling and then moving eastward in the 96-120
 hour time frame in response to a mid- to upper-level trough.  That
 model is considered an outlier as it is likely keeping Andres too
 deep over cool waters.  The official track forecast is a little to
 the north and slightly slower than the previous one after 72 hours.
 
 The hurricane is forecast to maintain its strength for about a day
 while it remains over warm water and in an environment of
 decreasing shear.  Steady weakening is anticipated beyond that
 time, however, when Andres moves over progressively cooler water
 and into a much more stable air mass.  The official intensity
 forecast is basically an update of the previous one and is in good
 agreement with the intensity model consensus.
 
 The 34-kt and 50-kt wind radii were expanded on the east side of
 the circulation based on a 1650 UTC ASCAT-B pass. The 12-ft sea
 radii were also expanded based on a recent altimeter pass that
 showed sea heights as high as 28 ft.
 
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  30/2100Z 14.8N 116.3W   90 KT 105 MPH
  12H  31/0600Z 15.4N 117.4W   90 KT 105 MPH
  24H  31/1800Z 15.9N 118.6W   85 KT 100 MPH
  36H  01/0600Z 16.3N 119.8W   75 KT  85 MPH
  48H  01/1800Z 16.9N 121.2W   65 KT  75 MPH
  72H  02/1800Z 18.5N 124.2W   55 KT  65 MPH
  96H  03/1800Z 19.5N 127.3W   40 KT  45 MPH
 120H  04/1800Z 19.5N 129.0W   30 KT  35 MPH
 
 $$
 Forecaster Cangialosi
 
 

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