000
AXPZ20 KNHC 281542
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON MAY 28 2007

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

BASED ON 1200TC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...SPECIAL FEATURES...
TROPICAL DEPRESSION ONE-E AT 13.0N 113.1W WITH 1005 MB AT 1500 
UTC MOVING W AT 6 KT.  NUMEROUS MODERATE TO STRONG CONVECTION 
WITHIN 90 NM SW SEMICIRCLE.  FAVORABLE SEA SURFACE TEMPERATURES 
AND UPPER ENVIRONMENT JUSTIFY FORECAST FOR SLOW DEVELOPMENT TO 
TROPICAL STORM WITHIN NEXT 18-24 HRS. 

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE AXIS ALONG...12N87W 6N103W 7N125W 
7N140W.  SCATTERED MODERATE ISOLATED STRONG CONVECTION E OF 89W.
SCATTERED MODERATE TO STRONG CONVECTION WITHIN 120 NM OF AXIS 
FROM 99W TO 115W.

...DISCUSSION...
WEAK MIDDLE LEVEL AND STRONG UPPER LEVEL TROUGH EXTEND FROM 
32N125W TO 20N136W THEN TO 23N140W.  WEAK 75 KT SW JET CORE 
ADVECTS TROPICAL MOISTURE WITHIN 240 NM OF TROUGH AXIS BUT STILL 
REMAINS FAR FROM LAND MASSES AND LACKS LOW LEVEL LIFTING 
MECHANISM TO PRODUCE SIGNIFICANT WEATHER.  AIR MASS NW OF AXIS 
FAIRLY DRY.  TROUGH LIKELY TO BE BLOCKED FROM ANY FURTHER 
SOUTHWARD INTRUSION BY WELL ESTABLISHED RIDGE ANCHORED IN PLACE 
BY THREE ANTICYCLONES...FIRST AT 10N136W SUPPORTING JET CORE.  
SECOND ANTICYCLONE AT 13N118W ENHANCE OUTFLOW OVER T.D. ONE-E
AND ALLOWS FURTHER INTENSIFICATION TO TROPICAL STORM POSSIBLY 
WITHIN NEXT 18-24 HRS.  THIRD ONE 14N90W HELPS BRING TROPICAL 
MOISTURE FROM SOUTH AMERICA INTO E PAC ITCZ REGION WHERE 
EQUATORIAL TROUGH MAINTAINS ACTIVE CONVECTION THROUGH E OF 115W. 

AIR MASS N OF 16N REMAINS VERY DRY...EXCEPT ABOVE JET CORE...
AND MAINTAINS CAP ON VERTICAL CLOUD DEVELOPMENT.  MOST OF AREA 
UNDER BROKEN TO OVERCAST STRATIFIED LOW CLOUDS.  

AT THE SURFACE...
WEAK HIGH PRES CENTER 1024 MB AT 37N133W HAS RIDGE EXTEND SE TO 
15N115W. TRADES REMAIN LIGHT.

$$
WALLY BARNES