000
WTPZ41 KNHC 101445
TCDEP1

Tropical Storm Sergio Discussion Number  45
NWS National Hurricane Center Miami FL       EP212018
800 AM PDT Wed Oct 10 2018

The cloud pattern associated with Sergio has not changed very much,
and it consists of a cyclonically curved convective band surrounding
a large and ragged eye feature. Since the convection is weaker, the
Dvorak estimates suggest that winds are gradually decreasing, and
the initial intensity has been lowered to 55 kt.  Some fluctuations
in intensity are likely during the next 12 to 24 hours while the
cyclone is still moving over relatively warm waters and is embedded
in a low shear environment. Both of these factors will become
unfavorable soon, and consequently, the NHC forecast calls for
weakening.  Sergio, however, is expected to still be a tropical
storm by the time it approaches the Baja California peninsula. After
that time, Sergio will move over mainland Mexico and weaken much
faster.

Sergio is moving toward the northeast or 055 degrees at 11 kt. The
cyclone is embedded within the southwesterly winds associated
with a large mid-latitude trough, and this flow pattern will
continue to steer Sergio toward the northeast with an increase in
forward speed. The forecast track brings the center of a weakened
Sergio over the central portion of the Baja California peninsula in
about 2 days, but winds along the coast are anticipated to increase
earlier. Track models are in very good agreement, and consequently
the guidance envelope is quite tight. The NHC forecast is not
different from the previous one and is in the middle of the guidance
envelope.

The primary threat associated with Sergio and its remnants continues
to be life-threatening flash flooding and mudslides within
mountainous terrain in the Mexico state of Sonora, the U.S. Southern
Plains, and the Ozarks through the weekend. For more information
about this potential hazard, see products from the Weather
Prediction Center and your local weather forecast office.


FORECAST POSITIONS AND MAX WINDS

INIT  10/1500Z 18.4N 123.5W   55 KT  65 MPH
 12H  11/0000Z 19.7N 121.6W   50 KT  60 MPH
 24H  11/1200Z 22.0N 119.0W   50 KT  60 MPH
 36H  12/0000Z 24.5N 116.2W   45 KT  50 MPH
 48H  12/1200Z 27.0N 113.0W   40 KT  45 MPH
 72H  13/1200Z 31.5N 104.5W   25 KT  30 MPH...POST-TROP/INLAND
 96H  14/1200Z...DISSIPATED

$$
Forecaster Avila