000
AXPZ20 KNHC 292209
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI JUL 29 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2115 UTC.

...ITCZ/MONSOON TROUGH...
MONSOON TROUGH AXIS FROM 11N86W TO 09N101W TO 12N115W TO 11N121W 
TO 12N128W TO 10N137W...THEN ITCZ TO 10N140W. SCATTERED MODERATE 
TO STRONG CONVECTION WITHIN 240 NM OF AXIS FROM 91W TO 99W.  
SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 180 NM OF 
AXIS FROM 115W-123W.  ISOLATED MODERATE CONVECTION WITHIN 75 NM N
OF AXIS FROM 123W TO 140W.

...DISCUSSION...
UPPER LEVEL CYCLONIC VORTEX AT 26N131W HAS TROUGH EXTEND E TO 
SECOND SMALLER VORTEX AT 22N112W.  TROUGH SQUEEZE ANTICYCLONE TO 
17N119W ABOVE WEAK SURFACE LOW PRES CENTER PRESENTLY AT 12N117W. 
THE THREE FEATURES MAINTAIN A DRY AIR MASS OVER MOST OF E PAC 
REGION N OF MONSOON TROUGH/ITCZ AND W OF 108W.  ONLY DIFFERING 
ITEM IS DIVERGING FLOW ALOFT SE OF ANTICYCLONE ENHANCING 
CONVECTION N OF SURFACE LOW PRES.  

NE SWELLS FROM GALE FORCE WINDS WELL N OF E PAC AFFECTING BASIN  
N OF 26N W OF 130W.  WINDS DIMINISH BY SUN BUT LINGERING 8-9 FT 
NE SWELL REMAIN THROUGH FORECAST PERIOD. 

FRESH MONSOON SW FLOW FROM 05N-09N BETWEEN 80W-120W WITH SEAS TO 
9 FT REMAIN IN SE PORTION OF BASIN THROUGH PERIOD.  GLOBAL 
MODELS DIFFER IN SOLUTIONS REGARDING LOW PRES 1010 MB AT 10N94W 
BUT STRENGTHENING IS LIKELY AS UPPER LEVEL CONDITIONS REMAIN 
FAVORABLE FOR DEVELOPMENT...ALTHOUGH NOT FOR LONG.  WHICH 
INDICATE THAT ANY DEVELOPMENT SHOULD BE SHORT-LIVED. 
  
$$
WALLY BARNES