000
AXPZ20 KNHC 122208
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN DEC 12 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ALONG 05N77W TO 
07N90W TO 05N100W TO 07N110W TO 09N125W.  AXIS AGAIN CONTINUES 
FROM 09N132W TO 08N140W.  SCATTERED MODERATE CONVECTION WITHIN 
120 NM OF AXIS E OF 82W.

...DISCUSSION...
A WEAKENING 1026 MB SURFACE HIGH PRES LOCATED JUST N OF AREA 
NEAR 33N128W WITH RIDGE EXTENDING OVER FORECAST WATERS SE TO 
17N113W AND SW TO BEYOND 27N140W. THE PRESSURE GRADIENT BETWEEN 
THIS FEATURE AND LOWER PRESSURE NEAR THE ITCZ IS SUPPORTING 
FRESH TRADE WINDS OF 20 KT FROM 08N TO 18N W OF 130W. THE FRESH 
TRADES WILL DECREASE IN AREAL EXTENT IN ABOUT A DAY AS THE HIGH 
PRESSURE CONTINUES TO WEAKEN AS DOES THE PRESSURE GRADIENT. A 
STATIONARY FRONT IS LOCATED JUST NW OF ARE AREA SHOULD REMAIN 
JUST OUTSIDE OF THE BOUNDARY BEFORE DISSIPATING THROUGH LATE 
MON.

A SUBSIDING NW SWELL AFFECTS MUCH OF THE REGIONAL WATERS S OF 
22N W OF 100W. WITHIN 48 HOURS...8 FT SEAS W OF 105W WILL BE 
CONFINED TO A SMALL AREA FROM 10N TO 18N W OF 135W IN NE 
TRADEWIND SWELL. 

GAP WINDS...
A STRONG AND FAST MOVING COLD FRONT IS CURRENTLY LOCATED ACROSS 
THE SOUTHERN GULF OF MEXICO AND INTO THE BAY OF CAMPECHE.  AHEAD 
OF THE FRONT...WINDS ARE ALREADY FUNNELING THROUGH THE CHIVELA 
PASS AND INTO THE GULF OF TEHUANTEPEC.  MEXICAN STATION MMIT HAS 
SHOWN WINDS 40 TO 45 KT WITH GUSTS 50 TO 55 KT SINCE 19Z.  WHILE 
NO IN SITU MARINE OBSERVATIONS ARE AVAILABLE...IT IS ANALYZED 
THAT THE MARINE GALE HAS COMMENCED.  GFS AND ECMWF BOTH SHOW 10 
M SURFACE WINDS OF 45 KT.  GIVEN THE WINDS ALREADY HIGHER THAN 
ANTICIPATED...WILL GO WITH STORM WARNING BEGINNING IN 12 
HR...AND DROPPING BELOW THAT THRESHOLD BY 36 HR...BUT CONTINUING 
WITH GALE THROUGH 48 HR.

AS THE COLD FRONT AND ASSOCIATED WIND SURGE CONTINUES TO MOVE 
EASTWARD INTO THE WESTERN CARIBBEAN...WINDS FUNNELING THROUGH 
THE CENTRAL AMERICA PASSES WILL PRODUCE FRESH TO STRONG WINDS 
OVER THE GULFS OF FONSECA AND PAPAGAYO BY LATE MONDAY NIGHT AND 
THE GULF OF PANAMA BY TUESDAY MORNING.

$$
AL/LANDSEA