ZCZC MIATCDEP3 ALL
TTAA00 KNHC DDHHMM

TROPICAL STORM RACHEL DISCUSSION NUMBER   5
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP182014
800 AM PDT THU SEP 25 2014

The northeasterly shear that has been affecting the cyclone
during the past day or so appears to be decreasing, with the center
of Rachel now located beneath the cold cloud tops.  Dvorak intensity
estimates from both TAFB and SAB support an initial wind speed of 45
kt for this advisory.  The shear is expected to further decrease
over the next 24 to 36 hours and additional strengthening is likely
during this period.  The new NHC intensity forecast is above the
previous forecast and close to the SHIPS/LGEM guidance.  After 48
hours, Rachel will be moving over slightly cooler water and into a
drier airmass, which should cause steady weakening late in the
forecast period.

A recent SSMIS overpass was very helpful in locating the center
this morning.  The fixes indicate an initial motion of 295 degrees
at about 11 kt. Rachel should continue moving west-northwestward to
the south of a mid-level ridge over Mexico during the next 24 to 36
hours.  After that time, a trough approaching the west coast of the
United States will create a break in the ridge which should cause
Rachel to turn northwestward.  During the 3 to 5 day period, there
continues to be large differences in the model solutions.  The GFS,
GFDL, and HWRF take the cyclone northward, then northeastward, while
the ECMWF and UKMET show a weaker cyclone becoming nearly stationary
well southwest of the Baja peninsula.  The NHC track leans toward
the more northward solution, but it is not nearly as fast or as
far east as the GFS and GFDL models at days 4 and 5.

FORECAST POSITIONS AND MAX WINDS

INIT  25/1500Z 16.3N 109.6W   45 KT  50 MPH
 12H  26/0000Z 17.1N 111.0W   50 KT  60 MPH
 24H  26/1200Z 18.2N 112.9W   55 KT  65 MPH
 36H  27/0000Z 19.0N 114.2W   55 KT  65 MPH
 48H  27/1200Z 19.8N 115.0W   60 KT  70 MPH
 72H  28/1200Z 21.5N 115.8W   55 KT  65 MPH
 96H  29/1200Z 22.7N 115.5W   45 KT  50 MPH
120H  30/1200Z 23.5N 115.0W   30 KT  35 MPH

$$
Forecaster Brown

NNNN