AXPZ20 KNHC 250915
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Tue Sep 25 2018
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 Twenty-E centered near 14.5N 107.2W at
25/0900 UTC or 320 nm SSW of Manzanillo Mexico moving W at 8 kt.
Estimated minimum central pressure is 1006 mb. Maximum sustained
wind speed is 30 kt with gusts to 40 kt near the center.
Scattered moderate isolated strong convection organizing in
bands within 120 nm east and 240 nm west semicircles of center.
See latest NHC forecast/advisory under AWIPS/WMO headers
MIATCPEP5/WTPZ35 KNHC for more details.
A tropical wave is analyzed from 04N100W to 17N101W with
scattered moderate isolated strong convection north of 10N
within 150 nm east of the wave axis.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends W off the Caribbean coast of Colombia
at 09N76W, and continues west across the Gulf of Panama to the
Pacific coast of Costa Rica at 09N84W to the tropical wave at
13N101W where it loses identity. The monsoon trough resumes
southwest of Tropical Depression 20-E near 14N110W and wiggles
southwest to 09N138W. A north to south trough is analyzed from
08N138W to 16N139W with scattered moderate isolated strong
convection south of 09N within 150 nm of the trough axis.
Scattered moderate isolated strong convection is observed within
240 nm either side of a line from 06N83W to 14N97W, within 120
nm of 19N106W, within 90 nm of 17N117W, and from 07N to 14N
between 120W and 135W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
See the Special Features paragraph above. A ridge extending from
22N116W to 21N112W will continue to gradually retract northwest
during the middle of the week as Tropical Cyclone 20-E tracks
northerly. Gentle to moderate northwest flow is forecast west of
the Baja California through Fri, with much uncertainty
Gulf of California: Moderate to locally fresh southerly winds
forecast across the gulf waters north of 30N through early Tue.
Otherwise, light to gentle variable winds expected across the
gulf waters through Fri.
Gulf of Tehuantepec: Fresh to strong northerly flow forecast
through Thu except briefly relaxing during the mid afternoons.
A strong drainage event expected on Thu night into early Fri
as a tropical low passes to the south.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Gulf of Papagayo: Fresh to locally strong east nocturnal
drainage flow expected through early Wed with a surface low
developing near 10N93W Wed night.
Light and variable winds are forecast through Wed morning
elsewhere north of the monsoon trough is meandering between 09N
and 12N. Moderate southwest flow is forecast south of the
monsoon trough. The pressure gradient will begin to tighten on
Wed night as a surface low develops near 10N93W and moves west of
the ares by early Fri.
REMAINDER OF THE AREA...
See the Special Features paragraph above. Otherwise, a broad
ridge continues across the subtropics accompanied by moderate to
locally fresh anticyclonic flow south of 23N west of 120W.