000
AXPZ20 KNHC 202124
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT NOV 20 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 
2100 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE AXIS EXTENDS FROM 10N85W TO 
10N104W THEN CONTINUE FROM 10N124W TO 09N140W. NO SIGNIFICANT 
CONVECTION.

...DISCUSSION...
A BROAD UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION 
OFF THE WASHINGTON COAST SWD TO 28N130W. THIS TROUGH HAS 
PROVIDED SUPPORT FOR A COLD FRONT WHICH EXTENDS FROM 30N124W TO 
27N140W. FRESH N TO NE WINDS WITH SEAS 8 TO 12 FT IN NW SWELL 
ARE BEHIND THE FRONT. THE COLD FRONT WILL LOSE ITS UPPER LEVEL 
SUPPORT AND DISSIPATE AS THE UPPER TROUGH WILL LIFT OUT OVER THE 
NEXT 24-48 HOURS. 

STRONG HIGH PRESSURE BUILDING BEHIND THE FRONT WILL INCREASE 
TRADES FROM 12N TO 15N W OF 130W IN 24 HOURS...AND WILL EXPAND 
FROM 13N TO 23N W OF 118W IN 48 HOURS. A SECOND SURGE OF NW 
SWELL OF 9 TO 14 FT TO SPREAD SWD INTO THE AREA N OF 23N W OF 
120W BY MON NIGHT. 

GAP WINDS...
LATEST ASCAT PASS INDICATES THAT SUSTAINED GALE FORCE WINDS HAVE 
DIMINISHED OVER THE GULF OF TEHUANTEPEC. WINDS ARE FORECAST TO 
GRADUALLY WEAKEN OVER THE NEXT 48 HOURS TO LESS THAN 20 KT BY 
MON AFTERNOON. 

FRESH TO STRONG WINDS OVER THE WESTERN CARIBBEAN ARE FUNNELING 
THROUGH THE CENTRAL AMERICA PASSES...BRINGING FRESH WINDS INTO 
THE GULF OF PAPAGAYO. THESE WINDS WILL PULSE WITH THE STRONGEST 
WINDS DURING THE OVERNIGHT AND EARLY MORNING HOURS WITH THE AID 
OF NOCTURNAL DRAINAGE FLOW OFF THE MOUNTAINOUS TERRAIN. 

$$
AL