000
AXPZ20 KNHC 201554
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                         
1605 UTC SUN DEC 20 2015

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.               
 
...SPECIAL FEATURE...

A GALE WARNING REMAINS IN EFFECT FOR THE GULF OF TEHUANTEPEC.
THE MOST RECENT SCATTEROMETER PASS SHOWED NORTHERLY WINDS IN THE
30-40 KT RANGE DOWNSTREAM OF THE GULF TO NEAR 13N95W WHILE AN
ALTIMETER PASS INDICATED SEAS TO 17 FT NEAR 15N95W. THESE WINDS
WILL GRADUALLY DIMINISH OVER THE NEXT 24-36 HOURS AS THE COOL
AND DRY MASS OF AIR OVER THE GULF OF MEXICO MODIFIES AND SHIFTS
EASTWARD. WINDS ARE EXPECTED TO DIMINISH BELOW GALE FORCE BY
EARLY MON MORNING...AND TO 20 TO 25 KT BY MON EVENING. THE PLUME
OF SHORT PERIOD NE SEAS GENERATED FROM THIS STRONG GAP WIND
EVENT CONTINUES TO MIX WITH LONGER PERIOD NW SWELL COVERING
ROUGHLY THE WATERS SOUTH OF 14N BETWEEN 92W AND 110W. WINDS WILL
DIMINISH TO 20 KT OR LESS AND SEAS SUBSIDE TO LESS THAN 8 FT BY
LATE MON/EARLY TUE. LOOKING AHEAD...GLOBAL MODELS ARE NOT
INDICATING ANY STRONG GAP WINDS THROUGH THE GULF OF TEHUANTEPEC
FOR THE REMAINDER OF THE WEEK.
   
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            

A SURFACE TROUGH EXTENDS FROM 07N77W TO 05N90W. THE ITCZ AXIS
CONTINUES FROM 05N90W TO 06N98W TO 04N110W TO 05N121W TO BEYOND
01N140W. A CLUSTER OF MODERATE TO STRONG CONVECTION IS NOTED
FROM 3.5N TO 5.5N BETWEEN 79W AND 81W. SCATTERED MODERATE
CONVECTION IS FROM 1.5N TO 6.0N BETWEEN 81W AND 87W. NUMEROUS
MODERATE ISOLATED STRONG CONVECTION CAN BE FOUND FROM 04N TO 07N
BETWEEN 119W AND 124W. SCATTERED MODERATE CONVECTION IS
ELSEWHERE FROM 03N TO 08N BETWEEN 115 AND 127W...AND S OF 04N W
OF 124W. 

...DISCUSSION...

A COLD FRONT EXTENDS FROM NORTHERN BAJA CALIFORNIA TO NEAR
27N120W THEN CONTINUES AS A DISSIPATING COLD FRONT TO 24N130W TO
BEYOND 21N140W. THE FRONT WILL CONTINUE TO DISSIPATE OVER THE
FORECAST WATERS DURING THE NEXT 24 HOURS. A STRONG 1033 MB HIGH
PRES FOLLOWS THE FRONT AND WILL MOVE EASTWARD...REACHING A
POSITION NEAR 32N148W BY EARLY MON MORNING...AND NEAR 33N146W BY
EARLY TUE MORNING. UNDER THIS SCENARIO...THE PRESSURE GRADIENT
WILL TIGHTEN ACROSS THE TROPICS N OF THE ITCZ WITH FRESH TO
STRONG NE TRADES COVERING A LARGE ROUGHLY FROM 04N TO 24N W OF
110W. THE PRES GRADIENT WILL CONTINUE TO TIGHTEN ON TUE WITH
INCREASING WINDS AND SEAS JUST OFF THE BAJA CALIFORNIA PENINSULA
AND NEAR CABO CORRIENTES. SEAS ARE FORECAST TO BUILD TO 13-14 FT
WITHIN THE AREA OF THE TRADE WINDS ON TUE. THE NW SWELL IN THE
WAKE OF THE FRONT WILL MERGE WITH THE WAVES GENERATED BY THE
TRADE WINDS AS THE FRONT DISSIPATES.  
  
GULF OF PAPAGAYO...BUILDING HIGH PRES ACROSS THE WESTERN ATLC
CURRENTLY SUPPORTS STRONG TO MINIMAL GALE FORCE TRADE WINDS IN
THE SOUTH-CENTRAL CARIBBEAN. THESE WINDS ARE FUNNELING THROUGH
THE GAPS ACROSS CENTRAL AMERICA INTO THE EPAC REGION ALLOWING
WINDS TO INCREASE ACROSS THE GULF OF PAPAGAYO AND THE GULF OF
FONSECA. A RECENT SCATTEROMETER PASS PROVIDES OBSERVATIONS OF 20-
30 KT NE WINDS EXTENDING DOWNSTREAM OF THESE GULFS REACHING NEAR
09N91W. EXPECT THESE WINDS TO GRADUALLY DIMINISH TO 20-25 KT
THIS EVENING...THEN CONTINUE THROUGH MON MORNING. EXPECT 20-25
KT CONDITIONS ON MON AND TUE NIGHTS.
 
$$
GR