000
AXPZ20 KNHC 260949
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN DEC 26 2010

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...
AXIS ALONG 05N77W TO 05N93W TO 08N110W TO 09N140W.  NO 
SIGNIFICANT CONVECTION.

...DISCUSSION...
LARGE AMPLITUDE NEGATIVELY TILTED DEEP LAYER TROUGH AXIS EXTENDS 
FROM GULF OF ALASKA TO 32N115W THEN TURN SW TO 12N127W. 
ASSOCIATED COLD FRONT EXTENDS ALONG 32N121W TO 22N130W TO 
21N135W.  TROUGH AXIS SWINGS NE AS WELL ANCHORED DOWNSTREAM 
ANTICYCLONE BLOCKS FURTHER SE INTRUSION.  LACK OF UPPER LEVEL 
SUPPORT WEAKENS COLD FRONT AS IT ENTERS BAJA CALIFORNIA.  AIR 
MASS OVER MOST OF BASIN REMAINS FAIRLY DRY ALTHOUGH MINOR 
PATCHES OF MOISTURE REMAIN NEAR FRONT AND WEAK SURFACE TROUGH 
ALONG 123W EMBEDDED IN ITCZ.

ELSEWHERE AT THE SURFACE...
HIGH PRES CENTER 1018 MB AT 25N119W DISSIPATES UNDER ATTACK BY 
COLD FRONT.  STRONGER HIGH PRES 1025 MB BUILDS BEHIND FRONT 
INCREASING NE TRADES W OF 120W BY END OF FORECAST PERIOD. TRADES 
EXPAND IN AREAL COVERAGE WITH BUILDING SEAS TO 12 FT W OF 125W. 

GULF OF TEHUANTEPEC...STRONG COLD NORTHERLY FLOWING ACROSS 
ISTHMUS BEGAN SHOWING OVER GULF OF TEHUANTEPEC WITH TIMING WELL 
MARKED BY GLOBAL MODEL GUIDANCE.  FAST MOVING COLD FRONT IN GULF 
OF MEXICO BRINGS GALE FORCE WINDS WITHIN 6 HRS...BUT QUICKLY 
VEERS SE EFFECTIVELY SHUTTING DOWN FLOW WITHIN 30-36 HRS FROM 
ONSET.  EVENT PROMPTS LARGE PLUME OF NE SWELL BY END OF TUE... 
REACHING AS FAR S AS 07N AND W TO 105W.

GULF OF PAPAGAYO...COLD FRONT FROM PARAGRAPH ABOVE ENTER NW 
CARIBBEAN LATER TODAY WITH NEAR GALE FORCE N-NE WINDS WHICH SEEP 
ACROSS CENTRAL AMERICA INTO GULF OF PAPAGAYO THEN EVENTUALLY 
INTO GULF OF PANAMA.  STRONG WINDS EXPECTED TO LAST BEYOND END 
OF FORECAST PERIOD.

$$
WALLY BARNES