181 
 WTPZ42 KNHC 302031
 TCDEP2
 
 Tropical Depression Seven-E Discussion Number   1
 NWS National Hurricane Center Miami FL       EP072018
 400 PM CDT Sat Jun 30 2018
 
 The disturbance located well south of Mexico has become better
 organized during the day.  Recent visible imagery indicates that the
 surface center has become better defined, and TAFB and SAB both
 provided a data-T number of 2.0.  On this basis, the system has been
 designated as Tropical Depression Seven-E with an initial intensity
 of 30 kt.
 
 The depression has been moving steadily west-northwestward at 11 kt
 today, steered by a mid-level ridge extending from central Mexico
 westward over much of the eastern North Pacific.  This ridge
 will likely be the dominant steering feature throughout the forecast
 period, and the cyclone should continue on a west-northwest heading
 at around the same forward speed through the middle of next week.
 All of the dynamical models forecast this general scenario and I
 have no reason to favor any one particular model, so the official
 track forecast is very close to the multi-model consensus through
 day 5.
 
 While the organization of the cyclone has improved today, the
 surface circulation remains fairly broad, and deep convection is
 limited to the northern semicircle of the circulation.  In addition,
 deep-layer shear of around 15 kt, as analyzed by the GFS and ECMWF,
 is currently affecting the depression.  Because of these factors,
 any initial intensification will likely be slow to occur.  After
 about 24 hours, the shear is forecast to decrease, which should
 allow the depression to become better organized and strengthen at a
 quicker rate.  The dynamical-statistical models bring the cyclone to
 near major hurricane intensity by day 4, while the dynamical models
 generally show more modest strengthening.  The NHC intensity
 forecast is near the intensity consensus for the first 36 hours, and
 a little above it, closer to DSHP and LGEM, from 48-96 h. By the end
 of the forecast period, the cyclone will reach cooler waters, which
 should result in rapid weakening.
 
 FORECAST POSITIONS AND MAX WINDS
 
 INIT  30/2100Z 11.2N 104.4W   30 KT  35 MPH
  12H  01/0600Z 11.6N 106.2W   35 KT  40 MPH
  24H  01/1800Z 12.2N 108.5W   40 KT  45 MPH
  36H  02/0600Z 12.9N 110.6W   50 KT  60 MPH
  48H  02/1800Z 13.5N 112.7W   65 KT  75 MPH
  72H  03/1800Z 15.0N 117.0W   90 KT 105 MPH
  96H  04/1800Z 17.0N 122.0W   90 KT 105 MPH
 120H  05/1800Z 19.5N 127.0W   60 KT  70 MPH
 
 $$
 Forecaster Zelinsky
 
 

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