000
AXPZ20 KNHC 151508
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1500 UTC Sun Dec 15 2019

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 1200 UTC surface analysis and satellite imagery through
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from 08N78W to 08N95W. The ITCZ 
continues from 08N95W to 09N123W. It resumes from 11N130W to
10N134W to 11N138W. Scattered moderate convection is noted from 
07N to 09N between 95W and 99W, and from 07N to 09N between 109W 
and 113W.

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

In the Gulf of Tehuantepec: a strong cold front will move into 
the northwest Gulf of Mexico Mon night. The front will shift 
southward across the western Gulf of Mexico, reaching the Bay of 
Campeche Tue. High pressure will build southward across the 
Sierra Madre Oriental in the wake of the front. The pressure 
gradient between this building high pressure, and the equatorial 
trough in the eastern north Pacific will usher in the next gale 
force gap wind event Tue night. This will be a strong gap wind 
event, with wind speeds possibly reaching minimal storm force, 
and seas building in excess of 20 ft on Wed. Gale conditions are 
forecast to prevail through Fri. 

A ridge extends from high pressure centered near 35N134W to near
the Revillagigedo Islands. The pressure gradient between this
ridge and a surface trough across the Gulf of California is
supporting fresh to strong winds off the coast of Baja California
Norte. Northerly swell continues to propagate across the forecast
area, with seas near 13 ft off the coast of Baja California
Norte, and seas greater than 8 ft covering the offshore waters W
of 106W. The area of high pressure will weaken over the next 24
hours. This will loosen the pressure gradient and diminish winds
off the coast of Baja California. The NW swell will slowly
subside, and fall below 8 ft by Tue. A fresh set of NW swell will
propagate into the waters off Baja California Norte Wed evening,
with seas building to near 11 ft Thu.

High pressure building over the Great Basin region will support 
fresh to strong NW winds across the Gulf of California late Mon 
through early Wed.

OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND 
WITHIN 750 NM OF ECUADOR... 

Moderate to fresh winds are expected across the Gulf of 
Papagayo, increasing to fresh to strong Wed, and continuing 
through Fri. Elsewhere, gentle to moderate south to southwest 
monsoon flow will persist across the offshore waters of Costa 
Rica, Panama, Colombia, and Ecuador, while light to gentle flow 
will dominate across the Gulf of Panama. 

REMAINDER OF THE AREA...

A ridge extends from high pressure of 1027 MB, centered near 
35N134W, to near the Revillagigedo Islands. The pressure gradient
between this area of high pressure and lower pressure in the
vicinity of the ITCZ is supporting moderate to fresh winds N of
the ITCZ and W of 120W. NW swell continues across the forecast 
waters, with seas 8 ft or greater covering much of the waters W 
of 107W. The NW swell will gradually subside over the next couple
of days, and areal coverage of seas 8 ft or greater will
decrease. Another round of large, long- period NW swell will
propagate into the NW waters Mon, and spread SE across the area
through the week. By Fri, seas 8 ft or greater will once again
cover much of the forecast waters N of 05N and W of 112W.

$$
AL