AXPZ20 KNHC 251000
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0845 UTC Thu Aug 25 2016
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 0600 UTC surface analysis and satellite imagery through
Tropical Depression 13-E has developed into a tropical storm.
The center of Tropical Storm Lester at 25/0900 UTC is near 16.2N
111.6W, or about 160 nm to the south-southwest of Socorro
Island, or about 415 nm to the south-southwest of the southern
tip of Baja California. Lester is moving west-northwestward, or
295 degrees, 10 knots. The estimated minimum central pressure is
1005 mb. The maximum sustained wind speeds are 35 knots with
gusts to 45 knots. Convective precipitation: Numerous strong
within 60 nm of the center in the northwestern semicircle.
Scattered moderate to isolated strong within 75 nm of the center
in the southeastern semicircle, and from 120 nm to 180 nm of the
center in the northeastern quadrant. Please read the NHC
forecast/ advisory under AWIPS/WMO headers MIATCMEP3/WTPZ23 KNHC
or the public bulletin under MIATCPEP3/ WTPZ33 KNHC for more
A tropical wave is along 133W/134W from 16N southward, moving
westward 15 knots. A 1008 mb low pressure center is near
12N126W. Convective precipitation: scattered strong within 240
nm of the low center from southwest of the center to north of
the center. isolated moderate within 30 nm on either side of the
tropical wave. Fresh NE trade winds cover the area from 13N to
20N from 127W westward. The sea heights range from 6 feet to 7
feet. Environmental conditions are conducive for a gradual
improvement in organization of this system. It has a medium
chance for tropical cyclone development during the next 48 hours.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends from 10N85W to 07N97W to 11N107W.
Convective precipitation: Numerous strong from 05N to 08N
between 81W and 83W, and within 120 nm to the south of the
monsoon trough between 97W and 100W. Scattered moderate to
isolated strong within 90 nm to the south of the monsoon trough
between 84W and 86W, and within 180 nm to the south of the
monsoon trough between 102W and 106W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
A narrow surface ridge extends from the NE Pacific southeastward
through 30N128W to 28N125W to 24N118W. This ridge will change
little during the upcoming weekend, and combine with the
persistent trough meandering along the Baja California peninsula
and Gulf of California, in order to produce mainly light to
moderate northerly flow prevailing outside of the Gulf of
California. Expect mainly light to gentle southerly flow In the
Gulf of California, except for occasionally fresh wind flow in
the northern Gulf where the pressure gradient will be slightly
Active convection associated with Tropical Storm Lester, in
the southwestern corner of PMZ023 and in the southeastern corner
of PMZ015, will move to the west of the area later today. East
to northeast winds of 15-20 kt occurring across the waters this
morning will diminish gradually during the day today, and become
light and variable as a weak ridge builds across the area behind
the exiting tropical storm.
High pressure in the Gulf of Mexico continues to drive 20-30 kt
northerly winds across the Gulf of Tehuantepec with sea heights
reaching 9 feet. The winds and seas will diminish today in the
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Moderate to locally fresh offshore winds are expected across
most of the area e of 95W and north of the monsoon trough today
until the early afternoon.
The weak 1018 mb center of the post-tropical remnant low of Kay
is near 24N127W. No deep convective precipitation is present
with this feature. The remnant low will continue to move west-
southwestward, and gradually dissipate into an open trough later
today. The wind speeds in the vicinity of the low center are
20 knots or less. the sea heights range from 5 feet to 7 feet.
A broad surface ridge covers the remainder of the area,
extending from a large 1041 mb high near 50N141W. The low
pressure center that is along 126W and its associated tropical
wave will move westward during the next few days. the surface
pressure gradient that exists between the monsoon trough and the
ridge will yield fresh winds across the trade wind belt,
generally from 21n southward, from just to the northeast of the
low center beyond 140W. Sea heights ranging from 6 feet to 8
feet in this area in mixed swell will increase slightly to a
range from 7 feet to 9 feet during this time. A large area of
fresh southwesterly monsoonal flow is supporting seas of 8 to 9
feet from 07N northward between 115W and 125W. The strength and
areal coverage of these fresh winds will increase to the south
and southeast of the low center as it shifts westward during the
next few days. The sea heights will increase to 6 feet to 8
feet in mixed south and southwest swell.