AXPZ20 KNHC 261611
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1520 UTC Tue Sep 26 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
Based on 1200 UTC surface analysis and satellite imagery
through 1500 UTC.
..INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough axis extends from 1006 mb low pressure south
of the Gulf of Tehuantepec near 15N94W, to 1008 mb low pressure
near 13N125W to beyond 10N140W. Numerous moderate to isolated
strong convection is noted from 13N to 16N between 92W and 96W,
and from 12N to 14N between 120W and 125W. Scattered moderate
convection is also noted from 12N to 14N between 100W and 103W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
The remnant low pressure of Pilar just to the southwest of Los
Cabos, although there is no significant convection or winds associated
with the low pressure. The low may linger for another over the
southern Gulf of California before dissipating. Meanwhile, a weak
pressure pattern over the Mexican offshore waters north of 20N
will allow gentle to moderate breezes and slight seas to persist
through late week. Farther south, the monsoon trough will remain
active over the next several days, allowing weak low pressure to
persist south of the Gulf of Tehuantepec through late week.
Showers and thunderstorms are ongoing near this low pressure
currently. Strong high pressure building over the Gulf of Mexico
north of the area will promote a pulse of fresh to strong gap
winds into the Gulf of Tehuantepec Fri night into early Sat.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
An active monsoon trough along and inland of the coasts 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,
with gentle to moderate variable winds north of the trough
into Sat. Winds will freshen in this region over the weekend in
response to a developing area of low pressure over Central
America. Active convection will prevail across the regional
waters for the next few days.
Long period SE to S swell will maintain 5 to 6 ft seas west of
Ecuador and south of the Equator during the next few days.
REMAINDER OF THE AREA...
Fresh to strong winds occurring around the 1008 mb low pressure
embedded in the monsoon trough near 113N125W are supporting an
associated area of 8 to 10 ft seas in mixed swell within 300 nm
in the southern semicircle of the low pressure. Monsoonal SW
winds will remain fresh to strong across this general area
through mid week, then subside.
Otherwise, weakened high pressure centered well N of the area
and low pressure associated with the monsoon trough will maintain
light to moderate trade winds W of 120W into Sat.