000
AXPZ20 KNHC 210956
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE JUL 21 2009

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...TROPICAL WAVES...
TROPICAL WAVE ALONG 83W N OF 04N MOVING W 20 AT KT UNDER LARGE 
AREA OF UPPER LEVEL DIFFLUENT PATTERN ENHANCING ITS DEEP 
CONVECTION AHEAD OF AXIS.  FAVORABLE CONDITIONS EXPECTED TO 
CONTINUE FOR AT LEAST 24-48 HRS ALLOWING SYSTEM TO EXPLOIT 
ABUNDANT AVAILABLE MOISTURE.  DEEP AMPLITUDE UPPER LEVEL TROUGH 
JUST N OF AREA IN GULF OF MEXICO EVENTUALLY DIGS INTO ITS PATH 
WELL BEYOND FORECAST PERIOD POSSIBLE CURTAILING ANY FURTHER 
DEVELOPMENT.  PRESENTLY...INFLUENCE FROM UPPER TROUGH HAVE 
EFFECTIVELY CUT OFF CREST OF WAVE N OF HONDURAS WHILE 
CONTRIBUTING TO MENTIONED DIFFLUENT FLOW.

TROPICAL WAVE ALONG 119W FROM 05N TO 14N MOVE W AT 20 KT.  
SIMILARLY TO PREVIOUS ONE...THIS WAVE MOVES UNDER A WIDE AREA OF 
DIFFLUENCE ALOFT THAT ENHANCES DEEP CONVECTION AHEAD OF AXIS.  
ABUNDANT MOISTURE IS ALSO AVAILABLE AND MODEL GUIDANCE 
INTENSIFIES SYSTEM THROUGH NEXT 48 HRS.
 
...ITCZ...
AXIS ALONG 07N84W TO 09N115W TO 07N140W.  SCATTERED MODERATE TO 
STRONG WITHIN 210 NM S OF AXIS E OF 95W. SCATTERED MODERATE TO 
STRONG WITHIN 180 NM OF N AND 90 NM S OF AXIS FROM 118W-128W.

...DISCUSSION...
COMPLEX CYCLONIC CIRCULATION WITH DUAL EDDIES AT 19N127W AND 
24N124W AND RIDGE W OF 134W KEEP AIR MASS FAIRLY DRY N OF 15N W 
OF 125W.  DOWNSTREAM ANTICYCLONE AT 13N115W CONTRIBUTING TO 
DIFFLUENT PATTERN OVER WAVE AT 119W.  UPPER LEVEL TROUGH CUTS 
BETWEEN THIS ANTICYCLONE AND ANOTHER OVER SWRN CARIBBEAN 
SPLITTING FLOW JUST AHEAD OF TROPICAL WAVE ALONG 83W ENHANCING 
DEEP CONVECTION.

NE TO E FRESH GAP WINDS IN GULF OF PAPAGAYO AND DOWNSTREAM WILL 
START DIMINISHING TODAY AS TROPICAL WAVE SHIFT WIND DIRECTION.  
LARGE SW SWELLS INVADING SRN LATITUDES FROM ACROSS EQUATOR 
EXPECTED TO CONTINUE THROUGH FORECAST PERIOD.  SEAS WILL PEAK 
NEAR 12 FT BY END OF FORECAST PERIOD THEN BEGIN SUBSIDING.  

$$
WALLY BARNES