000
AXPZ20 KNHC 202208
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT MAY 20 2006

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 
2130 UTC.

...ITCZ...
ITCZ AXIS ALONG 9N84W 12N94W 10N117W 
8N126W 5N140W.  SCATTERED MODERATE TO STRONG WITHIN 120 NM S OF 
AXIS FROM 80W TO 94W...WITHIN 150 NM OF AXIS FROM 101W TO 121W 
AND WITHIN 120 NM N OF AXIS W OF 130W.

...DISCUSSION...
W OF 110W...
DEEP LAYER TROUGH ENTER E PAC FORECAST WATERS FROM 32N132W TO 
22N140W.  FAIRLY DRY AIR MASS WITHIN 240 NM W OF AXIS.  JET 
STREAM 105 KT DRAGS MOISTURE ALOFT AHEAD OF AXIS TO CYCLONIC 
VORTEX WELL N OF AREA.  TROUGH DIGGING SE SUPPORTS COLD FRONT 
WHICH EXTENDS FROM 30N128W TO 23N140W.  BROAD MID / UPPER LEVEL 
ANTICYCLONE 11N114W WITH ELONGATED RIDGE TO 32N110W COVERS AREA 
N OF 13N WITH DRY AIRMASS RESULT OF MODERATE TO STRONG SUBSIDENCE
DUE TO CONFLUENT AIR MASS ALOFT. 

HIGH PRES RIDGE MAINTAINS GOOD E FLOW ALOFT OVER ITCZ ADVECTING 
TROPICAL MOISTURE OUT OF SOUTH AMERICA CONTINENT ALL THE WAY TO  
140W.

AT THE SURFACE...WINDS BEHIND COLD FRONT REMAIN STRONG BUT IT IS 
THE LARGE SWELL SPREADING S BEHIND THAT WILL AFFECT THE MOST.  
NWW3 BRINGS 15 FT WHICH APPEAR IN LINE WITH SHIP REPORTS OF 13 FT
JUST N OF AREA...UP TO 18 FT REMAIN JUST N OF 30N.     

E OF 110W...
UPPER LEVEL CYCLONIC CIRCULATION OVER S TEXAS COAST HAS WEAK 
TROUGH DIG S INTO TO 10N100W.  MODERATE TO STRONG SUBSIDENCE WAS 
INDICATED OVER MEXICO EXCEPT EXTREME S CORNER.  DIFFLUENT UPPER 
LEVEL FLOW WITH DOWNSTREAM UPPER LEVEL RIDGE ENHANCES ITCZ DEEP 
CONVECTION E OF 95W. 

$$
WALLY BARNES