Skip Navigation Links
NOAA NOAA United States Department of Commerce

Potential Tropical Cyclone FOURTEEN-E


ZCZC MIATCDEP4 ALL
TTAA00 KNHC DDHHMM

Potential Tropical Cyclone Fourteen-E Discussion Number   2
NWS National Hurricane Center Miami FL       EP142017
900 PM MDT Tue Aug 29 2017

Satellite images indicate that the disturbance just off the
southwest coast of Mexico is gradually becoming better organized.
The system is developing some banding features, especially over the
western semicircle.  However, the circulation remains broad and
there is no indication of a well-defined center at this time.  The
initial wind speed is held at 25 kt, in agreement with a Dvorak
classification from TAFB.  The environmental conditions are
conducive for the disturbance to strengthen, and it will likely
become a tropical storm on Wednesday.  Additional strengthening
seems likely through about 72 hours, and it is possible that the
disturbance could reach hurricane strength.  After that time,
however, decreasing SSTs and drier air should end the strengthening
trend and cause weakening.  The NHC intensity forecast lies near the
high end of the guidance, and it is very similar to the previous
forecast.

The initial motion of the system is difficult to determine since
there is no clear center, but satellite fixes suggest that the
disturbance is moving northwestward at 9 kt.  A slower northwestward
to north-northwestward motion is expected during the next 2 to 3
days, followed by a turn to the left beyond that time when the
system moves on the south side of a mid-level ridge over the
western United States.  The models have shifted to the east this
cycle, and the new NHC track forecast has been adjusted in that
direction.  This forecast takes the center of the system close to
Baja California Sur in the 48- to 72-h time frame.  Based on the new
forecast, the government of Mexico has expanded the Hurricane Watch
northward on the west coast of Baja California Sur.

It is important to note that very heavy rain is possible outside of
the watch/warning area in southwestern Mexico.  These rains could
cause life-threatening flooding and mudslides.  In addition,
wind gusts to tropical-storm-force are possible along the coast of
Michoacan, Colima and Jalisco states through early Wednesday due to
the system's large circulation.

The National Hurricane Center now has the option to issue
advisories, watches, and warnings for disturbances that are not yet
a tropical cyclone, but which pose the threat of bringing tropical
storm or hurricane conditions to land areas within 48 hours.  Under
previous policy this was not possible.  These systems are known as
Potential Tropical Cyclones in advisory products and are numbered
from the same list as depressions.

Because of the threat to Baja California Sur, advisories are being
issued on Potential Tropical Cyclone Fourteen-E.  Advisory packages
will continue until the threat of tropical-storm-force winds for
land areas sufficiently diminishes, although if the system becomes a
tropical cyclone, the normal rules for discontinuing advisories
would apply.  Users should be aware that forecast uncertainty for
disturbances is generally larger than for tropical cyclones,
especially beyond 48-72 hours.

FORECAST POSITIONS AND MAX WINDS

INIT  30/0300Z 17.7N 107.9W   25 KT  30 MPH...POTENTIAL TROP CYCLONE
 12H  30/1200Z 18.8N 108.6W   30 KT  35 MPH...POTENTIAL TROP CYCLONE
 24H  31/0000Z 19.7N 109.2W   35 KT  40 MPH...TROPICAL STORM
 36H  31/1200Z 21.0N 109.8W   45 KT  50 MPH
 48H  01/0000Z 22.1N 110.4W   55 KT  65 MPH
 72H  02/0000Z 24.1N 112.2W   60 KT  70 MPH
 96H  03/0000Z 25.7N 114.8W   45 KT  50 MPH
120H  04/0000Z 27.3N 117.5W   30 KT  35 MPH

$$
Forecaster Cangialosi

NNNN