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 WTPZ45 KNHC 272032
 Tropical Storm Miriam Discussion Number   7
 NWS National Hurricane Center Miami FL       EP152018
 200 PM PDT Mon Aug 27 2018
 Miriam has become a little better organized since the last advisory,
 and the convective banding has become better defined around the
 low-level center.  However, this has not yet resulted in an
 increase of the various satellite intensity estimates, which remain
 mostly near 55 kt.  Based on this, the initial intensity remains a
 possibly conservative 55 kt.  Satellite imagery continues to
 indicate northwesterly to northerly vertical shear affecting Miriam,
 with cirrus clouds from the outer band to the north blowing into the
 central convection.
 The initial motion is 270/13.  A large low- to mid-level ridge to
 the north of Miriam should continue to steer it westward for the
 next 36-48 h with some decrease in forward speed.  After that,
 a large mid- to upper-level low to the northeast of the Hawaiian
 Islands is expected to cause the ridge to break between 140W-150W,
 with Miriam turning northwestward and north-northwestward in
 response.  The track guidance is in good agreement on this
 scenario, but there remain some differences in Miriam's forward
 speed after recurvature between the faster ECMWF/UKMET and the
 slower GFS.  The new forecast track is similar to the previous
 track through 72 h, then is nudged a little to the east based on an
 eastward shift in the consensus models.
 The global models continue to suggest a gradual increase in
 northwesterly shear over Miriam during the next day or so, followed
 by decreased shear from 24-48 h.  There is some divergence in the
 intensity guidance through 72 h, with the SHIPS/LGEM models showing
 less strengthening than the HWRF/HMON/corrected consensus models.
 This part of the new intensity forecast is little changed from the
 previous forecast and lies between these two model camps. After
 72 h, increasing southwesterly shear and cooler waters are expected
 to cause Miriam to weaken.
 INIT  27/2100Z 14.0N 131.8W   55 KT  65 MPH
  12H  28/0600Z 14.0N 133.5W   65 KT  75 MPH
  24H  28/1800Z 13.9N 135.5W   70 KT  80 MPH
  36H  29/0600Z 14.0N 137.5W   75 KT  85 MPH
  48H  29/1800Z 14.5N 139.0W   85 KT 100 MPH
  72H  30/1800Z 16.5N 141.0W   85 KT 100 MPH
  96H  31/1800Z 20.0N 142.0W   75 KT  85 MPH
 120H  01/1800Z 24.5N 143.5W   50 KT  60 MPH
 Forecaster Beven
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