000
AXPZ20 KNHC 120320
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED MAY 12 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0230 UTC.

...ITCZ...

ITCZ AXIS ALONG 04N80W TO 05N95W TO 08N105W TO 08N115W TO 
08N125W TO 07N140W. SCATTERED MODERATE CONVECTION IS WITHIN 150 
NM S OF THE AXIS BETWEEN 80W AND 85W...WITHIN 90 NM N OF THE 
AXIS BETWEEN 92W AND 94W...AND ALSO BETWEEN 104W AND 106W. 
SCATTERED MODERATE CONVECTION IS WITHIN 180 NM S OF THE AXIS 
BETWEEN 115W AND 118W...WITHIN 60 NM EITHER SIDE OF THE AXIS 
BETWEEN 126W AND 131W...AND WITHIN 150 NM S OF THE AXIS W OF 
137W.

...DISCUSSION...

AN UPPER LEVEL TROUGH EXTENDS SW INTO THE DISCUSSION AREA NEAR 
32N111W TO 15N122W. A THIN BAND OF UPPER LEVEL MOISTURE IS NOTED 
FROM 30N106W TO 18N122W WITH DRY AIR IN PLACE W OF THE TROUGH 
AXIS TO 135W. A REINFORCING UPPER LEVEL TROUGH EXTENDS FROM AN 
UPPER LEVEL CYCLONE CENTERED OVER NE UTAH TO THE SW ACROSS 
CALIFORNIA AND INTO THE DISCUSSION AREA NEAR 32N117W WITH UPPER 
LEVEL MOISTURE BEING ADVECTED TO THE NE JUST AHEAD OF THE TROUGH 
OVER NORTHERN BAJA CALIFORNIA AND THE NORTHERN GULF OF 
CALIFORNIA. A SECOND REINFORCING UPPER LEVEL TROUGH EXTENDS FROM 
NEAR POINT CONCEPTION CALIFORNIA TO 32N130W TO 27N140W.

AN UPPER LEVEL TROPICAL ANTICYCLONE IS POSITIONED NEAR 06N135W 
WITH A RIDGE EXTENDING ALONG 06N BETWEEN 115W AND 140W. 
CONVECTION IS BEING ENHANCED ALONG AND S OF THE RIDGE UNDER 
UPPER DIFFLUENCE ALONG THE ITCZ W OF 120W. ANOTHER UPPER LEVEL 
ANTICYCLONE IS CENTERED NEAR 10N100W. MID TO UPPER LEVEL 
MOISTURE IS BEING ADVECTED FROM THE ITCZ UP ALONG THE NW-N 
PERIPHERY OF THE ANTICYCLONE TO THE NE INTO CENTRAL MEXICO. 
CONVECTION IS ALSO BEING ENHANCED ALONG THE ITCZ BETWEEN 100W 
AND 110W ON THE SOUTH SIDE OF THE ANTICYCLONE. 

A DEEP UPPER LEVEL TROUGH EXTENDS FROM THE NE YUCATAN PENINSULA 
ACROSS GUATEMALA AND EL SALVADOR AND INTO THE DISCUSSION AREA 
NEAR 13N89W AND EXTENDING FARTHER TO THE S NEAR 07N90W. AN UPPER 
LEVEL CYCLONE HAS CLOSED OFF S OF THE TROUGH NEAR 04N89W. VERY 
DRY AIR IS NOTED ACROSS THIS AREA EXCEPT E OF THE TROUGH AXIS 
WHERE CONVECTION IS BEING ENHANCED ALONG THE ITCZ BETWEEN THE 
TROUGH AXIS AND AN UPPER LEVEL RIDGE EXTENDING FROM COLOMBIA TO 
THE NW OVER NICARAGUA.
 
AT THE SURFACE...A BROAD RIDGE AXIS DOMINATES THE MAJORITY OF 
THE DISCUSSION AREA WITH ITS AXIS MEANDERING FROM NEAR 32N135W 
TO 13N110W. NE TRADES IN THE 20-25 KT ARE SW OF THE RIDGE AXIS 
FROM 08N TO 27N W OF 123W. 20-30 KT NW-N WINDS ARE OCCURRING N 
OF 24N BETWEEN 111W AND 123W. NW-NE SWELLS ARE THE PRIMARY 
SWELLS OVER THE WATERS WHERE THE TRADES AND NW-N WINDS ARE 
OCCURRING WITH A SERIES OF LONG PERIOD CROSS EQUATORIAL 
SOUTHERLY SWELL GROUPS DOMINATING THE REMAINDER OF THE 
DISCUSSION AREA. THE HIGHEST COMBINED SEAS OF UP TO 12 FT ARE 
OCCURRING ALONG 10N W OF 134W. 

GAP WINDS...NE TO E WINDS AT 20 TO 25 KT ARE SURGING OVER THE 
GULF OF PAPAGAYO AND DOWNWIND TO NEAR 09N90W AND ARE EXPECTED TO 
PERSIST FOR AT LEAST THE NEXT 48 HOURS.

$$
LEWITSKY