000
AXPZ20 KNHC 241554
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SUN MAY 24 2009

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...TROPICAL WAVES...

A TROPICAL WAVE IS ALONG 92W FROM 04N TO 17N MOVING W AT 12 KT. 
CONVECTION IS ENHANCED WITHIN 90 NM E OF THE WAVE FROM 05N TO 
08N.

...ITCZ...

THE ITCZ AXIS EXTENDS ALONG 08N78W TO 12N95W TO 11N104W TO 
13N115W TO 05N140W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS NOTED FROM 03N TO 10N E OF 92W...AND WITHIN 120 NM 
EITHER SIDE OF A LINE FROM 09N104W TO 13N113W AND A LINE FROM 
10N121W TO 06N130W.

.DISCUSSION...

ALOFT...A MID LEVEL TROUGH EXTENDS SW ALONG 30N107W TO 21N111W 
TO 06N136W AND IS LOSING IDENTITY. THE UPPER LEVELS TO THE N OF 
18N ARE DOMINATED BY ZONAL FLOW. SOME UPPER MOISTURE IS NOTED N 
OF 18N W OF 125W RACING E IN THESE STRONG WESTERLIES. OTHERWISE 
THE UPPER LEVELS AREA DRY N OF 20N E OF 125W. 

A TROPICAL MID TO UPPER LEVEL ANTICYCLONE IS AT 09N90W WITH A 
RIDGE W ALONG 11N119W TO 06N128W AND A RIDGE E TO 07N84W. UPPER 
DIFFLUENCE HAS ENHANCED CONVECTION ALONG THE ITCZ BETWEEN 130W 
AND 84W WITH THE DEBRIS MOISTURE ADVECTED N TO ALONG 18N E OF 
115W WITH SOME OF THE DEBRIS MOISTURE ADVECTED E OF THE UPPER 
TROUGH ACROSS THE SOUTHERN CARIBBEAN.

.AT THE LOW LEVELS...A RIDGE EXTENDS ALONG 32N132W TO 20N110W. A 
WEAK SURFACE LOW 1011 MB IS NEAR 11N114W WITH THE TIGHTEST 
GRADIENT CURRENTLY N OF THE CENTER WITH WINDS TO 20 KT. THIS LOW 
IS EXPECTED TO MEANDER IN THE SAME AREA FOR A FEW MORE DAYS.

$$
NELSON