000
AXPZ20 KNHC 180338
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN DEC 18 2011

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...

MONSOON TROUGH AXIS FROM 09N84W TO 05N101W THEN ITCZ TO 10N116W 
TO 07N128W TO 08N135W.  SCATTERED MODERATE CONVECTION WITHIN 120 
NM OF AXIS FROM 116W AND 121W. 

...DISCUSSION...

UPPER LEVEL CYCLONE AT 31N119W STRONGLY SUPPORTS SURFACE LOW 
PRES 1016 MB AT 30N119W WHILE FRONTAL TROUGH HAS EFFECTIVELY 
DISSIPATED.  CYCLONE SHIFT E INLAND SUN DOOMING SURFACE LOW PRES 
TO DISSIPATE TONIGHT.  WEAK COLD FRONT APPROACH NORTHEASTERN  
BOUNDARY LATE MON WITH STRONG N BREEZE BUT IS NOT EXPECTED TO 
REACH S OF 30N...NEVERTHELESS ITS NW SWELLS UP TO 10-11 FT 
SHOULD EXTEND AS FAR S AS 22N.    

FRESH NE TRADEWINDS W OF 130W DIMINISH SUN BUT ARE EXPECTED TO 
EXPAND COVERAGE EASTWARD MON AS HIGH PRES IS SQUEEZED BY 
AFOREMENTIONED APPROACHING COLD FRONT.

GAP WINDS...
GULF OF TEHUANTEPEC...STRONG N BREEZE ACROSS GULF OF TEHUANTEPEC 
EXPECTED TO REACH GALE FORCE TONIGHT.  EVENT BECOMES SHORT LIVED 
AS HIGH PRES OVER GULF OF MEXICO SHIFTS E EASING PRES GRADIENT 
OVER THE ISTHMUS MON. 

GULF OF PAPAGAYO...SURFACE LOW PRES 1010 MB OVER COLOMBIA FORCE 
STRONG E WINDS OVER WESTERN CARIBBEAN FINDING THEIR WAY ACROSS 
NICARAGUA MOUNTAIN GAPS AND REACH GULF OF PAPAGAYO IN E PAC.  
WIND EXPECTED TO WEAKEN LATE MON AS LOW PRES BECOMES ILL DEFINED.

$$
WALLY BARNES