000
AXPZ20 KNHC 291624
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON MAY 29 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1445 UTC.

...SPECIAL FEATURES...
TROPICAL STORM ALETTA AT 16.0N 101.4W AT 1500 UTC DRIFTING W AT 
2 KT.  ESTIMATED MINIMUM CENTRAL PRESSURE 1002 MB.  MAXIMUM 
SUSTAINED WIND SPEED 35 GUSTS TO 45 KT.  NUMEROUS STRONG 
CONVECTION WITHIN 75 NM E SEMICIRCLE AND 30 NM W SEMICIRCLE.  
SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. 

...TROPICAL WAVES...
TROPICAL WAVE ALONG 96W FROM 2N TO 13N MOVE W 10 KT.  SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 45 NM OF 5N97W.  
WHILE UPPER ENVIRONMENT IS NOT CONDUCIVE FOR INTENSIFICATION... 
IT IS EXPECTED TO BECOME MORE FAVORABLE AS WAVE MOVES FURTHER 
WEST WITH POSSIBLE INFLOW OF MOIST WARM CROSS-EQUATORIAL AIR 
MASS WELL BEYOND 48-72 HRS. 

..ITCZ...
ITCZ AXIS ALONG...9N83W 7N96W 11N106W 12N114W 7N128W 6N140W.  
ISOLATED MODERATE WITHIN 60 NM OF AXIS E OF 90W. SCATTERED 
MODERATE TO STRONG WITHIN 60 NM OF 5N97W.  SCATTERED MODERATE
TO STRONG WITHIN 90 NM OF AXIS W OF 122W.

...DISCUSSION...
MID/UPPER LEVEL TROUGH FROM 32N116W TO POSSIBLE DEVELOPING CUT 
OFF VORTEX NEAR 23N136W THEN TO 17N140W.  VERY DRY AIRMASS DUE 
TO SUBSIDENCE ALOFT ENTIRE AREA NW OF TROUGH AXIS.  WEAK 50 KT 
JET CORE ADVECTS MOISTURE FROM CONVECTIVE DEBRIS OUT OF ITCZ W 
OF 125W.  LAID DOWN ORIENTATION OF TROUGH GIVES QUASI-ZONAL FLOW 
SE OF AXIS N OF 15N W OF 100W. 

ANTICYCLONIC CIRCULATION CENTER AT 8N138W HAS UPPER RIDGE EXTEND 
TO 15N90W AND WILL BRINGING DRY UPPER AIR INTO VICINITY OF T.S. 
ALETTA IN 48 HRS.   

MID/UPPER LEVEL RIDGE OVER SOUTH AMERICA MAINTAINS MOIST 
EASTERLY FLOW ALOFT OVER ITCZ EAST OF 100W.

AT THE SURFACE...HIGH PRES CENTERED NEAR 32N133W AND ASSOCIATED 
CIRCULATION COVERS AREA N OF 12N W OF 110W WITH BRISK TRADES 
WHICH WILL DECREASE AS HIGH PRES WEAKENS NEXT 24-36 HRS.  SWELLS 
FROM S OF EQUATOR INVADE E PAC S OF 10N FROM W OF 90W.  

$$
WALLY BARNES