000
AXPZ20 KNHC 042207
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Sat Mar 4 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
2145 UTC.

...SPECIAL FEATURES... 

Strong high pressure northeast of the region will support 30-35
KT north to northeast gap winds along a narrow across the Gulf 
of Tehuantepec through this evening, while a broad swath of 20-30
kt north to northeast encompasses the remainder of the gulf as 
well as downstream from the gulf to near 12N between 95W and 
97W. Seas of 10-15 ft are within the area of gale force winds 
while seas of 8-12 ft are within the area of 20-30 kt winds. 
Model guidance is on track in showing these gap winds diminishing
through Sunday as strong high pressure ridging extending from 
the Gulf of Mexico southwest to eastern Mexico slides eastward 
and the resultant tight pressure over southeastern Mexico and the
Isthmus of Mexico slackens. By Sunday evening, residual swell 
from this event is forecast to be located well south of the Gulf 
of Tehuantepec from near 09N to 13N between 95W-100W with seas 
of around 8 ft primarily in northeast swell. These seas will 
subside to less than 8 ft by late Sunday night. A pulse of strong
northerly flow will push through the Gulf of Tehuantepec on 
Monday norther pule with seas of 8-10 ft. This next round of gap 
flow will then diminish Monday afternoon with seas lowering to 
below 8 ft. See the latest NWS High Seas Forecast under AWIPS/WMO
headers MIAHSFEP2/FZPN03 KNHC for more details. 

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

The ITCZ axis extends from 02N100W to 03N110W to 04N120W. The 
ITCZ then resumes west of a surface trough analyzed from near 
04N122W to 12N118W. Isolated showers and thunderstorms are 
seen within 60 nm of the trough axis from 09N to 12N.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A tight pressure gradient associated with strong high pressure 
that extends from southeast U.S. to the Gulf of Mexico and to 
eastern Mexico is currently inducing gale force north to 
northeast winds over portions of the Gulf of Tehuantepec. Please 
see the special features section for more details. High pressure 
ridging across the northern and central waters supports gentle to
moderate northerly winds offshore Baja California and Mexico 
waters north of 18N with seas of 4 to 6 ft. Aside from the 
Tehuantepec gap winds and large swell from the gap winds between 
93W and 99W over the offshore waters, winds south of 18N are 
gentle to moderate with seas of 5 to 7 ft. On Monday, a cold 
front is forecast to move over the northeast waters accompanied 
by fresh northeast winds and long period northwest swell that 
will produce 8-10 ft seas offshore Baja California. By Tuesday, 
strong northwest winds will develop over the Gulf of California, 
with seas building to 8 ft. Another Tehuantepec wind event is 
forecast to begin early Thursday as a cold front crosses the Gulf
of Mexico. 

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

High pressure north and east of the region will continue to 
funnel fresh to strong northeast winds through the Gulf of 
Papagayo and surrounding waters throughout the forecast period.
During the late night and early morning hours, the strongest 
winds are expected as the regional coverage of strong winds expands
to include from 08N to 13N and Gulf of Fonseca, and as far west 
as 92W except to 04w through early Sunday. Seas will build to 8 
to 10 ft within this area as swell propagates westward and merges
with large swell propagating from the Gulf of Tehuantepec.

Over the Gulf of Panama...north to northeast winds will increase
to fresh to strong speeds tonight, then diminish during the late
afternoon hours of Monday. 

Elsewhere...light to gentle breezes and seas of 4 to 6 ft will 
prevail through early next week.

REMAINDER OF THE AREA... 

The combination between high pressure ridging over the northern 
and central waters and lower pressure in the tropics is 
producing fresh trades from 05N to 18N, east of 123W which is 
supporting 8 to 9 ft northeasterly swell west of a line from 
16N140W to 12N132W to 07N134W to 05N140W. The trades will 
decrease the next 24 hours as the high pressure weakens, with 
seas diminishing below 8 ft by early Sunday afternoon. A surface
trough extends from the ITCZ near 04N118W to 12N118W. Isolated 
showers are within 60 nm of the trough from 09N to 12N. A cold 
front will cross the northern waters beginning Sunday night. The 
leading edge of an 8 to 10 ft batch of northwesterly swell will 
accompany this cold front. By Tuesday, the 8-10 ft swell will 
cover the waters north of a line from 25N115W to 16N140W.

$$
Aguirre