ZCZC MIATCDEP3 ALL
TTAA00 KNHC DDHHMM

TROPICAL STORM RACHEL DISCUSSION NUMBER  10
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP182014
200 PM PDT FRI SEP 26 2014

The center of Rachel appears to be reforming a little closer to the
deep convection, and in fact looks somewhat elongated on the latest
visible imagery. The SHIPS model and UW-CIMSS satellite analyses
still show about 10 kt of shear affecting the cyclone, and overall
there has been little net change to the cloud pattern today. The
initial intensity remains 45 kt based on the latest Dvorak estimate
from TAFB. The SHIPS model shows the shear decreasing over the next
24 hours, which should allow for some gradual strengthening, but the
SHIPS intensity forecast has trended downward this cycle along with
the GFDL. After 36 hours, gradual weakening is forecast as the
cyclone moves into a drier and more stable environment over
marginal SSTs and decay to a remnant low is expected in 4 to 5 days.
The NHC forecast has been adjusted downward a little in the short
range toward the latest IVCN intensity consensus and is close to
IVCN after that time.

Given the reformation of the center, the initial position is
southwest of the previous advisory. Smoothing through this short-
term motion yields a somewhat uncertain initial motion estimate of
295/10. The synoptic reasoning for the track forecast has not
changed. Rachel is forecast to turn gradually northward into a
break in the subtropical ridge with a decrease in forward speed
during the next couple of days. After that time, the decaying
cyclone is forecast to move little in a region of weak steering
currents, with a slow southwestward motion possible by the end
of the period. There continues to be a large spread in the track
guidance after 36 hours, with the GFS and GFDL taking the cyclone
farther north while the UKMET and ECMWF show a more westward to
southwestward motion. The new NHC forecast track is generally
between the two camps and is a little left of the TVCE multi-model
consensus and not far from the HWRF. This track is west of the
previous NHC advisory due to the initial position and motion.

FORECAST POSITIONS AND MAX WINDS

INIT  26/2100Z 18.1N 115.0W   45 KT  50 MPH
 12H  27/0600Z 18.7N 115.9W   50 KT  60 MPH
 24H  27/1800Z 19.7N 116.6W   55 KT  65 MPH
 36H  28/0600Z 20.6N 117.1W   55 KT  65 MPH
 48H  28/1800Z 21.3N 117.3W   50 KT  60 MPH
 72H  29/1800Z 22.0N 117.3W   40 KT  45 MPH
 96H  30/1800Z 22.0N 117.3W   30 KT  35 MPH
120H  01/1800Z 21.5N 117.5W   25 KT  30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Brennan

NNNN