000
AXPZ20 KNHC 251002
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
728 UTC Mon Sep 25 2017

Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 140W. The following information is
based on satellite imagery, weather observations, radar, and
meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
0900 UTC.

...SPECIAL FEATURES...

Tropical Storm Pilar is centered near near 22.2N 106.6W, or 
about 60 nm S of Mazatlan Mexico. Pilar has a central pressure 
of 1004 MB at 0900 UTC and is moving NNW or 340 DEG at 8 KT. 
Maximum sustained winds 35 KT gusts 45 KT. Scattered moderate to 
strong convection is within 120 nm of the coast of Mexico from 
21N to 24N. Pilar is expected to slowly track toward the NNW to N
through Tuesday night and move along or just offshore of the 
coastline. Interaction with land and vertical wind shear are 
causing rapid weakening of Pilar. Pilar is expected to become a 
tropical depression this afternoon and then dissipate by Tue 
evening. Heavy rainfall causing flash floods and mudslides 
remains possible for the Mexican states of Nayarit and southern 
Sinaloa through tonight. See the latest NHC Forecast/ Advisory 
under AWIPS/WMO headers MIATCMEP3/WTNT23 KNHC for more details.

..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...         

The monsoon trough extends from 11N74W to 10N82W to low pres 
1010 mb near 13.5N91.5W to 16N104W to 13N117W to low pres 1010 mb
near 14N126W to 11N135W to beyond 12N140W. Scattered moderate 
and isolated strong convection is seen from 01N to 09N between 
77W and 80W, from 06N to 10N between 91W and 110W and from 12N to
14N between 121W and 126W. Scattered moderate convection is 
present from 10N to 14N between 97W and 104W and from 08N to 11N 
between 133W and 138W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...  

Winds and seas associated with Tropical Storm Pilar will affect
the southern Gulf of California through Tuesday afternoon as
Pilar slowly tracks NNW and weakens. A high pressure ridge 
reaching SE into the waters west of Baja California will maintain
moderate NW winds along the pacific coast of Baja through 
tonight. The ridge will weaken in response to low pressure 
passing well to the north and NW winds will become gentle to 
moderate Tue through Thu night. Fresh SW to W monsoonal winds 
well offshore of the Gulf of Tehuantepec will generate SW wind 
waves in the SE waters and maintain seas in this area of 5-7 ft.

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR...

An active monsoon trough near the coast of Central America from 
Guatemala to Panama will remain the focus for active convection 
over the coastal waters the next few days. Expect moderate SW to
W winds to prevail south of the trough through Friday night. 
Farther south, gentle to moderate south to southwest winds will
generally persist south of 05N through Friday night. Long period
SE to S swell will decay and allow seas west of Ecuador and 
south of the Equator to subside from around 6 ft to around 5 ft 
during the next couple of days.

REMAINDER OF THE AREA...

NW to N swell generated by strong winds north of the area are 
producing 6 to 7 ft seas N of 25N between 118W and 130W. Rounds 
of reinforcing N swell will maintain seas in the region between 6
and 8 feet through Wed night. Fresh to strong winds around low 
pres embedded in the monsoon trough near 13.5N126W are supporting
a surrounding area of 8 to 10 ft seas in mixed swell. The low 
will shift to the ENE during the next couple of days. Otherwise, 
high pres centered well N of the area and low pressure associated
with the monsoon trough will maintain moderate to occasionally 
fresh trade winds W of 120W through tonight. Low pressure passing
north of the area will weaken the high, allowing trades to 
decrease during the second half of the week. 

$$
CAM