000
AXPZ20 KNHC 111558
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE MAY 11 2010

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.

...ITCZ...

THE ITCZ AXIS EXTENDS ALONG 05N77W TO 12N90W TO 05N110W TO 
05N140W. SCATTERED MODERATE TO STRONG CONVECTION IS OBSERVED 
WITHIN 120 NM EITHER SIDE OF A LINE FROM 08N77W TO 02N93W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 60 
NM EITHER SIDE OF A LINE FROM 07N84W TO 07N90W...WITHIN 15 NM OF 
A LINE FROM 05N96W TO 07N105W...AND ALSO WITHIN 150 NM LINE 
EITHER SIDE OF A LINE FROM 10N113W TO 05N120W TO 06N140W. 

...DISCUSSION...

AN UPPER TROUGH EXTENDS S INTO THE DISCUSSION AREA ALONG 32N116W 
TO 12N128W. A THIN BAND OF UPPER MOISTURE IS NOTED FROM 24N140W 
TO 19N128W WHERE THE MOISTURE BAND WIDENS TO ABOUT 240 NM AS IT 
TURNS NE TO 20N116W AND CONTINUES OVER THE BAJA PENINSULA AND 
OLD MEXICO TO NEAR 30N97W. OTHERWISE...UPPER DRY AIR IS 
INDICATED N OF 23N W OF 110W.

A MID TO UPPER LEVEL TROPICAL ANTICYCLONE IS ESTIMATED NEAR 
06N131W WITH A RIDGE EXTENDING E AND W ALONG 06N BETWEEN 115W 
AND 135W. A RIDGE AXIS IS ALSO EXTENDING NE TO NEAR 30N103W. 
UPPER DIFFLUENCE IS ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 
110W AND 140W WITH THE ASSOCIATED DENSE UPPER DEBRIS MOISTURE  
ADVECTED NE UNDER THE UPPER RIDGE...ROUGHLY WITHIN 180 NM OF A 
LINE FROM 10N114W TO 20N101W WHERE THE MOISTURE SIGNATURE 
BECOMES LESS DENSE AS IT CONTINUES NE AND E TO OVER THE NORTHERN 
GULF OF MEXICO. 

AN UPPER TROUGH EXTENDS S ACROSS CENTRAL AMERICA FROM 22N90W TO 
10N95W ACCOMPANIED BY DRY UPPER AIR TO THE N OF 10N BETWEEN 106W 
AND 88W. AN UPPER RIDGE EXTENDS W FROM S AMERICA TO A CREST OVER 
THE TROPICAL PACIFIC AT 09N90W. THE ASSOCIATED UPPER DIFFLUENCE 
UNDER THE RIDGE IS ENHANCING CONVECTION AS PREVIOUSLY DESCRIBED 
WITH THE RESULTANT DEBRIS MOISTURE ADVECTED NE ACROSS CENTRAL 
AMERICA E OF 87W AND OVER THE S CARIBBEAN.
 
AT THE SURFACE...A BROAD RIDGE AXIS DOMINATES MOST OF THE 
DISCUSSION AREA WITH ITS AXIS MEANDERING FROM 32N137W TO 
13N105W. NE TRADES IN THE 15 TO 20 KT RANGE ARE SW OF THE RIDGE 
AXIS FROM 06N TO 26N W OF 120W. NORTHERLY WINDS IN THE 20 KT 
RANGE ARE OCCURRING N OF 20N E OF THE RIDGE TO THE BAJA 
PENINSULA. THE ASSOCIATED N AND NE SWELLS ARE THE PRIMARY SWELL 
OVER THE WATERS N OF THE ITCZ W OF 110W. A NEAR SERIES OF LONG 
PERIOD SOUTHERLY SWELLS ARE CROSSING THE EQUATOR BETWEEN 105W 
AND 140W AND EXPECTED TO BUILD THE COMBINED SEAS TO ABOUT 11 FT 
OVER THE WATERS S OF 08N W OF 95W WED.  

GAP WINDS...NE TO E WINDS AT 20 TO 25 KT ARE SURGING OVER THE 
GULF OF PAPAGAYO AND EXPECTED TO CONTINUE FOR AT LEAST 48 HOURS.

$$
NELSON