AXPZ20 KNHC 272058
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2115 UTC Sat Aug 27 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 1800 UTC surface analysis and satellite imagery through
Hurricane Lester centered near 17.9N 119.6W at 27/2100 UTC moving
west or 270 degrees at 11 kt. Estimated minimum central pressure
is 973 mb. Maximum sustained wind speed is 90 kt with gusts to
110 kt. Additional strengthening is forecast during the next 24
hours. A well-defined eye is present with Lester along with
numerous moderate and scattered strong convection within 120 nm
in the east semicircle and within 90 nm in the west semicircle.
Lester will continue on a general westward motion, with an
increase in forward speed during the next couple of days. See
latest NHC forecast/advisory under AWIPS/WMO headers
MIATCMEP3/WTPZ23 KNHC for more details.
Tropical Storm Madeline centered near 15.7N 139.3W at 27/2100 UTC
moving northwest or 305 degrees at 9 kt. Estimated minimum central
pressure is 997 mb. Maximum sustained wind speed is 50 kt with
gusts to 60 kt. Numerous moderate and isolated strong convection
can be found within 75 nm in the northeast semicircle and within
180 nm in the southwest semicircle. Madeline will continue on a
general northwest motion in the next couple of days with a
decrease in forward speed. Madeline is forecast to move west of
140W and into the Central Pacific basin tonight, strengthening to
a hurricane during the day Sunday. See latest NHC forecast/advisory
under AWIPS/WMO headers MIATCMEP4/WTPZ24 KNHC for more details.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough axis extends from 09N79W to 13N97W to low
pressure near 10.5N109W to 09N114W, then resumes near 13N118W to
10N124W to 14N133W. Scattered moderate convection is within 210n
northeast of the axis between 91W and 99W, from 10N to 12N between
116W and 199W, within 60 nm south of the axis between 121W and
126W, and also from 12N to 15N between 131W and 134W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Hurricane Lester continues to move westward away from the area.
Moderate to fresh southerly winds over the northern Gulf of
California between local troughing and high pressure farther west
over the northeast Pacific will diminish this evening as the
trough weakens. Generally moderate northwest flow will persist
across the remainder of the waters off Baja California with
lighter winds farther south. An exception will be north of 27N and
west of 118W where fresh to locally strong northerly flow will
seep southward from off of the California coast by late Tuesday
night into early Wednesday helping to build fresh seas to 7 to 9
ft. Fresh northerly winds will pulse in the Gulf of Tehuantepec
late tonight into early Sunday, with nocturnal winds only pulsing
to moderate at best thereafter.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Light and moderate winds will continue to prevail on either side
of the monsoon trough for the next several days, with combined
seas of 4 to 7 ft mainly in cross equatorial southerly swell.
A broad surface ridge covers the remainder of the area, extending
from 1020 mb high pressure near 30N130W. A weak surface trough
extends from 28N135W to 24N137W, and will move west of 140W
Sunday. The pressure gradient between the ridge and Lester will
produce a band of moderate to fresh winds roughly from 18N to 22N,
with combined seas ranging from 5 to 7 feet.
Low pressure at 1010 mb is located near Clipperton Island at
10.5N109W. Convection is minimal near this low currently, and
prospects for tropical cyclone formation remain low through the
next several days at is tracks westward along the monsoon trough.
Model guidance shows moderate to fresh southwesterly monsoon flow
into the monsoon trough west of the low pressure from 07N to 12N
between 109W and 128W, with winds increasing to fresh to strong on
Sunday before diminishing back to moderate to fresh on Monday.
Seas currently up to 8 ft will build to 8 to 10 ft by Monday.