000
AXPZ20 KNHC 121604
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1605 UTC Mon Dec 12 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
meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1500 UTC.
  
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...  

The monsoon trough axis extends from 11N86W to 07N90W to 07N104W.
The ITCZ continues from 07N104W to 09N123W to 06N133W to
07N140W. Scattered moderate convection is south of Costa Rica
from 05N TO 09N between 81W and 86W. Scattered moderate to
isolated strong convection is from 08N to 14N between 120W
and 130W.

...DISCUSSION...   

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gulf of Tehuantepec: Strong north winds continue today north of
14N with max seas of 8 ft. Residual high pressure over southern
and eastern Mexico will continue to weaken, allowing winds to
diminish to around 20 kt by Tue evening. The surface pressure
gradient will tighten again over the Gulf of Tehuantepec to
produce 25 kt winds on Wed...30 kt Thu...and 35 kt gale Thu
evening through Fri. 

Moderate to fresh NW winds over the offshore waters north of 20N
will become gentle to moderate today through Thursday as seas
range between 4 and 6 ft. Light to gentle north winds will
prevail S of 17N through Wednesday. Between 17N and Mazatlan,
gentle to moderate northwest winds will prevail through
Wednesday, then become light through Friday.
     
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...

Fresh offshore winds are observed east of 90W in the Papagayo
region with seas less than 8 ft. A 1010 mb surface low over SW
Nicaragua near 11N86W today will move over the Pacific shortly.
Global models indicate some modest development of the low as it
moves westward away from the offshore waters Tuesday and
Wednesday. Latest global model forecasts show associated winds
remaining 25 kt or less.

REMAINDER OF THE AREA... 

A broad surface ridge over the NW forecast waters is anchored by
a 1022 mb high centered near 28N127W. Gentle to moderate north-
northwest flow is expected east of the high through Wednesday.
Moderate to fresh NE winds are situated between the ridge and the
ITCZ, or generally from 10N to 20N W of 130W. Combined seas reach
8 ft from 07N to 13N W of 136W. This area will shift west of
140W this evening. Low pressure and an attendant frontal
boundary northwest of the area will continue weakening the ridge
through Thursday. The front will briefly stall just inside the
far northwest waters on Wednesday and introduce winds of 20 to
25 kt and seas 8 to 10 ft. Then reinforcing cold air will push
the front east-southeastward across the northern waters Thursday
and Friday. NW swell generated behind the front will cause seas
to build N of 26N and W of 120W to 10 feet by Friday morning.
  
$$
Formosa