000
AXPZ20 KNHC 261510
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS FROM 08.5N83W TO 07N92W WHERE 
LOW LEVEL WINDS SUGGEST A TRANSITION TO ITCZ TO 07N92W TO 
08N120W TO 08N140W. SCATTERED MODERATE CONVECTION WAS NOTED 
WITHIN 120 NM N OF AXIS BETWEEN 110W AND 128W.

...DISCUSSION...

HIGH PRESSURE 1029 MB IS CENTERED NEAR 37N139W WITH RIDGE 
EXTENDING SE TO NEAR 17N108W. THE PRESSURE GRADIENT BETWEEN THE 
RIDGE AND LOWER PRESSURE IN THE VICINITY OF THE ITCZ IS 
MAINTAINING FRESH TO STRONG TRADEWINDS FROM 12N TO 18N W OF 
130W. THE RIDGE WILL REMAIN THROUGH THE FORECAST PERIOD WHICH 
WILL MAINTAIN THIS AREA OF FRESH TO STRONG TRADEWINDS.

THE HIGH PRESSURE CENTER WILL SHIFT SE AND CLOSER TO THE 
FORECAST AREA OVER THE NEXT 24 HOURS. THIS WILL TIGHTEN THE 
PRESSURE GRADIENT BETWEEN IT AND A TROUGH OF LOW PRESSURE OVER 
MEXICO WHICH WILL STRENGTHEN WINDS TO THE W OF BAJA CALIFORNIA 
BY THU MORNING. 

A FRESH SET OF NW SWELLS HAS ENTERED THE NW PART OF THE FORECAST 
AREA. SEAS ASSOCIATED WITH THIS SWELL WILL BE IN THE 8 TO 11 FT 
RANGE AS IT SPREADS S AND E OVER THE NEXT COUPLE OF DAYS. BY FRI 
MORNING...THE SWELL WILL COVER MUCH OF THE FORECAST AREA N OF 
20N W OF 110W.   

GAP WINDS...

GULF OF PAPAGAYO...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...NORTHERLY WINDS BEHIND A COLD FRONT OVER 
THE GULF OF MEXICO WILL START TO FUNNEL THROUGH THE ISTHMUS OF 
TEHUANTEPEC WITH NEAR GALE WINDS EXPECTED THIS AFTERNOON. WINDS 
WILL INCREASE TO GALE FORCE THIS EVENING AND PERSIST THROUGH THE 
OVERNIGHT HOURS BEFORE DIMINISHING BELOW GALE FORCE THU MORNING. 
WINDS WILL FURTHER DIMINISH...BELOW 20 KT BY THU EVENING...AS 
WINDS OVER THE GULF OF MEXICO VEER.

$$
AL