000
AXPZ20 KNHC 022139
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN DEC 02 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...
MONSOON TROUGH EXTENDS FROM 07N77W TO 06N79W TO 08N85W TO 06N92W 
THEN ITCZ TO 08N113W TO 06N132W TO BEYOND 07N140W.  SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM N AND 60 NM S 
OF ITCZ AXIS FROM 96W TO 131W.

...DISCUSSION...
ALOFT...UPPER LEVEL TROUGH RUNS FROM 32N113W TO 14N136W BRINGING 
VERY DRY AND STABLE AIR MASS W OF AXIS.  WEAK JET CORE 45 KT 
ADVECTS WHAT SMALL AMOUNTS OF MOISTURE AVAILABLE INTO SOUTHERN 
BAJA CALIFORNIA...BUT LITTLE IMPACT EXPECTED FROM IT AS REGION 
ALSO REMAINS FAIRLY STABLE.  ILL-DEFINED ELONGATED ANTICYCLONE 
AT 07N100W DOES A BETTER JOB IN ADVECTING CONVECTIVE DEBRIS 
MOISTURE FROM ITCZ NE UNTO CENTRAL AMERICA...BUT AGAIN DRY 
STABLE AIR MASS OVER CENTRAL AMERICA CURTAILS ANY SIGNIFICANT 
IMPACT.  

AT LOWER LEVELS...LARGE NW SWELLS GENERATED BY POWERFUL 
EXTRATROPICAL CYCLONE WELL N OF REGION PUSH INTO E PAC AND 
QUICKLY SPREAD S BEYOND THE EQUATOR W OF 110W.  SWELLS HAVE 
PEAKED TO 14 FT AND EXPECTED TO SUBSIDE TO 10-11 FT TONIGHT AND 
GET BELOW 8 FT N OF 20N MON...WHILE REMAINING NEAR 10 FT S OF 
20N DUE TO INCREASING NE TRADES.  

HIGH PRES CENTER 1022 MB AT 26N128W IS REINFORCED MON AND PUSHES 
LONG FETCH OF FRESH TO STRONG TRADES FROM 10N TO 20N W OF 120W 
...KEEPING SEAS IN 10-11 FT RANGE AS DEPICTED BY MWW3...UKMET 
AND EUROPEAN GUIDANCE.

GAP WINDS...
FRESH TO STRONG N TO NE BREEZE CONTINUE TO FUNNEL THROUGH 
CHIVELA PASS INTO GULF OF TEHUANTEPEC WITH SEAS OF 8-9 FT.  
WINDS EXPECTED TO DIMINISH LATE TONIGHT AND MON WITH SEAS 
SUBSIDING BELOW 8 FT...THEN BOTH WIND AND SEAS EXPECTED TO 
RETURN WED...AS DEPICTED BY ALL GLOBAL MODELS...BUT MOST LIKELY 
REMAINING BELOW GALE FORCE.

GULF OF PAPAGAYO WINDS PULSATE TO 20-25 KT DURING LATE NIGHT 
HOURS THEN DIMINISHING BELOW 20 KT DURING THE AFTERNOONS. 

$$
WALLY BARNES