000
AXPZ20 KNHC 260324
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED DEC 26 2012

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM 06N78W TO 06N97W. THE ITCZ 
EXTENDS FROM 06N97W TO 08N120W TO 06N140W. SCATTERED MODERATE 
CONVECTION IS NOTED WITHIN 60 NM N OF ITCZ BETWEEN 115W AND 125W.

...DISCUSSION...

GULF OF TEHUANTEPEC...
A COLD FRONT WILL PUSH RAPIDLY ACROSS THE GULF OF MEXICO...AND 
DELIVER STRONG N FLOW THROUGH THE ISTHMUS OF TEHUANTEPEC AND 
INTO THE GULF OF TEHUANTEPEC THROUGH WED AFTERNOON. WINDS WILL 
REACH GALE FORCE OVER THE GULF OF TEHUANTEPEC BY LATE 
AFTERNOON/EARLY EVENING...AND PERSIST THROUGH THE NIGHT BEFORE 
DIMINISHING BELOW GALE FORCE THU MORNING. GAP WINDS WILL RAPIDLY 
DIE OFF THROUGH THU AFTERNOON AS THE SHALLOW AIRMASS TO THE 
NORTH MODIFIES AND SHIFTS EASTWARD. 

OVER THE NE PACIFIC...AN UPPER DISTURBANCE N OF THE AREA 
MIGRATING EASTWARD TOWARD THE CALIFORNIA COAST IS SUPPORTING THE 
APPROACH OF A WEAK COLD FRONT S OF 30N W OF 130W. THE FRONT WILL 
SAG SE AND REACH FROM 30N125W TO 29N140W BY EARLY WED...BEFORE 
SHIFTING E AND DISSIPATING THROUGH THU NIGHT. THE ADVANCE OF THE 
FRONT WILL WEAKEN A SURFACE RIDGE EXTENDING E TO W ALONG 26N 
THAT HAD BEEN MAINTAINING AN AREA OF FRESH TO STRONG TRADES FROM 
07N TO 19N W OF 120W. THIS AREA OF TRADE WINDS WILL SHRINK IN 
SIZE FROM EAST TO WEST THROUGH WED AS THE RIDGE WEAKENS. 

1027 MB HIGH PRES BEHIND THE FRONT WILL BUILD S TO 30N THROUGH 
THU...ALLOWING FRESH TO STRONG NW TO N WINDS OFF THE NORTHERN 
COAST OF BAJA STARTING THU...AND A MINOR RESURGENCE OF FRESH TO 
STRONG TRADE WINDS TO THE S THROUGH SAT. 

SEAS OF 8 TO 11 FT ARE NOTED IN THE AREA OF TRADES IN A MIX OF 
LONG PERIOD NW SWELL AND FRESH NE SWELL. A NEW ROUND OF NW SWELL 
IS STARTING TO MOVE INTO THE AREA N OF 20N W OF 130W...AND WILL 
OVERTAKE MUCH OF THE AREA W OF 120W THROUGH LATE THU.

SW FLOW ALOFT ON THE EAST SIDE OF A PERSISTENT UPPER TROUGHING 
FROM 25N120W TO 10N135W IS AIDING MODEST CONVECTION ALONG THE 
ITCZ BETWEEN 115W AND 125W. 

$$
CHRISTENSEN