000
AXPZ20 KNHC 182158
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT AUG 18 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 100 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH FROM 10N85W TO 10N90W TO 12N100W TO 07N112W TO 
13N125W TO 11N131W TO 10N137W THEN ITCZ TO BEYOND 09N140W. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION FROM 05N TO 
TROUGH AXIS BETWEEN 89W AND 107W...AND WITHIN 30 NM OF 12N128W. 

...DISCUSSION...
UPPER LEVEL ANTICYCLONE OVER NORTHERN BAJA CALIFORNIA BRINGS 
MOISTURE BACK INTO E PAC N OF 22N E OF 120W.  REMNANTS OF HECTOR 
STILL LINGERING JUST W OF SOUTHERN TIP OF BAJA UNABLE TO TAP 
INTO IT AS IT DEMISE IS ALL BUT CERTAIN OVER THE COLD WATERS.
SECOND ANTICYCLONE OVER TROPICAL DEPRESSION HELENE ADVECTS 
ABUNDANT MOISTURE DEBRIS FROM SYSTEM ACROSS SOUTHERN MEXICO  
INTO E PAC E OF 120W.  WEAK TROUGH EXTEND FROM 19N104W TO 
10N110W SEPARATES ANTICYCLONES AND ALLOWS MODERATE DIVERGENT 
FLOW ALOFT TO ENHANCE SCATTERED MODERATE ISOLATED STRONG 
CONVECTION ALONG MONSOON TROUGH E OF 110W. 

...ELSEWHERE AT THE LOWER LEVELS...
LOW PRES CENTER 1010 MB...REMNANTS OF HECTOR...AT 23N116W 
CONTINUES TO WEAKEN AS IT DRIFT N-NE.  MOST OF CONVECTION AND 
WINDS ABOVE 20 KT ARE GONE AND LOW PRES EXPECTED TO DISSIPATE 
EARLY SUN. 

HIGH PRES CENTER 1020 MB AT 30N132W BLOCK MOVEMENT OF REMNANT 
LOW OF HECTOR...WHICH THEN DRIFTS N-NE TOWARD NORTHERN BAJA 
BEFORE DISSIPATING SUN.  HIGH PRES ALSO PROVIDE LIGHT TO 
MODERATE NE TRADES W OF 125W N OF MONSOON TROUGH.

LONG PERIOD CROSS EQUATORIAL S SWELL TO 8 FT SPREAD AS FAR N AS 
08N FROM 80W TO 120W BY LATE SUN.

$$
WALLY BARNES