Eastern North Pacific Tropical Weather Discussion (Text)

AXPZ20 KNHC 192140

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2140 UTC Sun Nov 19 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 1800 UTC surface analysis and satellite imagery through
2130 UTC.


Gulf of Tehuantepec Gale Warning: Strong high pressure is surging
down eastern Mexico while a cold front is also moving into the SW
Gulf of Mexico N of the area. While there have been no recent
observations in the Gulf of Tehuantepec, available guidance
indicates that northerly strong to minimal gale force winds have
commenced. Winds will continue to increase, approaching strong
gale force overnight tonight, then will diminish by Mon afternoon
as the gradient significantly slackens. Seas will rapidly build
to up to 17 ft during the strongest winds tonight. Northerly
winds will pulse to fresh to near gale force Mon night, then will
diminish to 20 kt or less Tue morning. Northerly flow will then
pulse to fresh to strong starting Wed morning with another gale
force wind event possible Wed night through Fri night.


The monsoon trough axis extends from 09N76W to 07N91W to 09N106W.
The intertropical convergence zone axis extends from 09N106W to
10N114W to 10N130W to 12N140W. Scattered moderate and isolated
strong convection is within an area bounded by 10N113W to
13N118W to 11N127W to 07N129W to 04N126W to 06N114W to 10N113W.



Please read the Special Features section above for information 
regarding the Gulf of Tehuantepec Gale Warning. 

A NW to SE oriented ridge just beyond 250 nm seaward will 
maintain moderate to locally fresh NW flow W of the Baja 
Peninsula through the evening when the pressure gradient will 
relax, supporting moderate NW flow later tonight through sunrise
Mon. Light N winds winds then are expected through Thu. A trough
is forecast to form from the central Baja Peninsula southward, 
on Thu night and Fri, accompanied by a light W to NW wind shift.
Expect seas in the 4 to 7 ft range today, with these conditions 
resuming again late in the week, with 3 to 5 ft seas during early
and mid part of the week. 

Gulf of California: Fresh to strong NW winds across the central
and northern gulf W of 110W will diminish tonight as the pressure
gradient relaxes. Moderate NW flow is then forecast across the 
entire gulf waters, becoming light by Mon evening. Moderate to 
locally fresh NW flow will resume across the entire gulf on Tue 
and Wed, then diminishing Thu through Fri.


Gulf of Papagayo:  Moderate to locally fresh NE drainage winds 
are forecast during the overnight hours tonight and on Mon 
night, then light drainage flow expected during the overnight 
hours through Thu night, with moderate to fresh nocturnal 
drainage resuming on Fri night.

Light and variable winds and 3 to 5 ft seas are expected 
elsewhere to the N of the monsoon trough, which has been 
meandering between 09N and 11N. Moderate to locally fresh 
southerly winds and 4 to 7 ft seas are forecast S of the monsoon
trough through the week. 


A tight pressure gradient is in place between a dissipating cold
front W of 140W and ridging to the E across the northern waters.
Associated scattered moderate convection is within an area
bounded by 28N132W to 30N132W to 30N140W to 21N140W to 28N132W.
The tight pressure gradient is supporting fresh to strong 
southerly flow in the NW corner of the discussion waters, along 
with 8 to 10 ft seas. Winds will increase to near gale force with
seas also building to 12 ft by early Mon with a lengthening 
fetch area. The front will dissipate prior to reaching 140W.

Additional cold fronts will approach 140W through the week, but
will stall through Wed night as high pressure holds. A weakening
front will manage to cross 140W by early Thu with an associated
area of large NW swell intruding prior to its arrival. NW swell
will build seas to 16 ft near 30N140W by Thu morning. The highest
seas will decay through the end of the week, but the edge of seas
of 8 ft or greater will manage to stretch across the waters N of
10N and W of 125W by Fri morning.

Elsewhere, fresh to locally strong trades are supporting seas to
8 ft within an area bounded by 14N129W to 16N132W to 15N137W to 
12N135W to 11N131W to 12N128W to 14N129W. Trades will diminish
slightly later tonight allowing for seas to subside to less than
8 ft.


Standard version of this page

Alternate Formats
About Alternates - E-Mail Advisories - RSS Feeds

Cyclone Forecasts
Latest Advisory - Past Advisories - About Advisories

Marine Forecasts
Latest Products - About Marine Products

Tools & Data
Satellite Imagery - US Weather Radar - Aircraft Recon - Local Data Archive - Forecast Verification - Deadliest/Costliest/Most Intense

Learn About Hurricanes
Storm Names Wind Scale - Prepare - Climatology - NHC Glossary - NHC Acronyms - Frequently Asked Questions - AOML Hurricane-Research Division

About Us
About NHC - Mission/Vision - Other NCEP Centers - NHC Staff - Visitor Information - NHC Library

Contact Us

NOAA/ National Weather Service
National Centers for Environmental Prediction
National Hurricane Center
11691 SW 17th Street
Miami, Florida, 33165-2149 USA
Privacy Policy
About Us
Career Opportunities
Page last modified: Sunday, 19-Nov-2017 21:40:47 UTC