ZCZC MIATCDEP5 ALL
TTAA00 KNHC DDHHMM

TROPICAL STORM DOLORES DISCUSSION NUMBER   9
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP052015
900 AM MDT MON JUL 13 2015

Dolores is gradually intensifying.  The cyclone is maintaining a
symmetric and very cold-topped central dense overcast, with the
center fully underneath the deepest convection. Very recently the
cyclone has also shed its outer bands while the inner core has
increased in organization.  The outflow remains somewhat restricted
to the west, however, and there still is some evidence of west-
northwesterly shear as a result of an upper-level trough to the
northwest. Dvorak classifications were T3.5/55 kt from both TAFB and
SAB at 1200 UTC. Since that time, there has been some further
increase in organization, and thus the initial intensity is set to
60 kt.

The initial motion estimate continues to be a steady 295/11. Dolores
should continue to be steered west-northwestward by a subtropical
ridge over the south-central United States during the next couple of
days. As the cyclone approaches the western periphery of this ridge,
the forward motion should decrease and the heading should become
west-northwestward to northwestward in 48 to 72 hours. After that
time, the ridge should rebuild somewhat to the northeast, which
should result in a slightly faster forward speed late in the
forecast period.  The GFS and ECMWF model solutions diverge
considerably after 72 hours, owing to the strength of the
subtropical ridge. The official forecast is a little right of the
previous one through 36 hours and very close to the multi-model
consensus after that time since the strength of the subtropical
ridge is still uncertain late in the forecast period.

Although environmental thermodynamics are quite conducive for
intensification, global models continue to show a persistent west-
northwesterly shear over Dolores during the next 24 hours.  The
shear, however, has not been enough to impede strengthening, with
the cyclone developing at about the standard T-number/day
climatological average.  SHIPS model output indicates a decrease in
shear in about 36 hours, and Dolores is expected to become a major
hurricane not long after that time.  With decreasing SSTs and a
drier and more stable atmosphere along Dolores' path after 96
hours, the cyclone is forecast to gradually spin down.  Ultimately,
the rate of decay will depend on how quickly Dolores gains latitude
late in the forecast period.  The official intensity forecast is
generally above the multi-model consensus and closest to SHIPS model
output.


FORECAST POSITIONS AND MAX WINDS

INIT  13/1500Z 17.1N 106.0W   60 KT  70 MPH
 12H  14/0000Z 17.5N 107.0W   70 KT  80 MPH
 24H  14/1200Z 17.8N 108.0W   80 KT  90 MPH
 36H  15/0000Z 18.1N 109.0W   90 KT 105 MPH
 48H  15/1200Z 18.4N 109.8W  100 KT 115 MPH
 72H  16/1200Z 19.7N 112.0W  105 KT 120 MPH
 96H  17/1200Z 21.2N 115.0W   90 KT 105 MPH
120H  18/1200Z 22.7N 118.3W   70 KT  80 MPH

$$
Forecaster Kimberlain

NNNN