000
AXPZ20 KNHC 252204
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE DEC 25 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH EXTENDS FROM 06N77W TO 07N92W. THE ITCZ 
EXTENDS FROM 07N92W TO 07N130W TO 06N140W. SCATTERED MODERATE 
CONVECTION WITHIN 60 NM S OF MONSOON TROUGH AXIS BETWEEN 80W AND 
90W. SCATTERED MODERATE CONVECTION WITHIN 60 NM N OF ITCZ 
BETWEEN 115W AND 125W. 

...DISCUSSION...

W OF 110W...
HIGH PRESSURE 1026 MB IS CENTERED NEAR 27N138W WITH RIDGE 
EXTENDING SE THROUGH THE  SOUTHERN BAJA PENINSULA. THE PRESSURE 
GRADIENT BETWEEN THE HIGH CENTER AND LOWER PRESSURE IN THE 
VICINITY OF THE ITCZ IS MAINTAINING FRESH TO STRONG TRADEWINDS 
FROM 07N TO 19N W OF 120W . THE PRESSURE GRADIENT BETWEEN THE 
RIDGE AND A TROUGH OF LOW PRESSURE OVER MEXICO IS SUPPORTING 
FRESH TO STRONG WINDS OFF THE COAST OF BAJA CALIFORNIA. 

THE HIGH PRESSURE CENTER WILL DISSIPATE OVER THE NEXT 24 HOURS 
ENABLING A WEAK COLD FRONT TO ENTER THE FORECAST AREA. THIS 
FRONT MOVE ACROSS THE N PART OF THE AREA AND DISSIPATE BY THU. 
THE PRESSURE GRADIENT WILL LOOSEN AS THE HIGH PRESSURE CENTER 
DISSIPATES...AND THE AREAL EXTENT OF THE FRESH TO STRONG 
TRADEWINDS WILL DECREASE. THE COLD FRONT WILL USHER IN A FRESH 
SET OF NW SWELLS EARLY WED...WITH SEAS PEAKING NEAR 11 FT WED 
BEFORE STARTING TO SLOWLY SUBSIDE.  

GAP WINDS...

GULF OF PAPAGAYO...MODERATE TO FRESH WINDS WILL PULSE OVER THE 
NEXT COUPLE OF DAYS WITH STRONGEST WINDS OCCURRING DURING THE 
OVERNIGHT AND EARLY MORNING HOURS WITH THE AID OF NOCTURNAL 
DRAINAGE FLOW. 

GULF OF TEHUANTEPEC...A COLD FRONT WILL PUSH THROUGH THE GULF OF 
MEXICO...DELIVERING A SURGE OF COLDER AND DRIER AIR DOWN THE 
COAST OF MEXICO TOWARD THE ISTHMUS OF TEHUANTEPEC LATE WED...AND 
INTO THE GULF OF TEHUANTEPEC STARTING LATE WED INTO EARLY THU. A 
GALE WARNING HAS BEEN ISSUED FOR THE GULF OF TEHUANTEPEC WED 
EVENING AND LASTING THOUGH THE OVERNIGHT HOURS BEFORE WINDS 
DIMINISH BELOW GALE FORCE BY THU MORNING. 

$$
CHRISTENSEN/AL