000 AXPZ20 KNHC 140946 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SAT MAY 14 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...ITCZ... THE ITCZ AXIS IS FLUCTUATING FROM 05N TO 06N BETWEEN 105W AND 140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 60 NM EITHER SIDE OF A LINE FROM 07N124W TO 07N131W TO 03N135W TO 05N140W. A MONSOON TROUGH IS ANALYZED ALONG 07N BETWEEN 82W AND 100W WITH SCATTERED MODERATE ISOLATED STRONG CONVECTION NOTED FROM 02N TO 10N TO THE E OF 87W. ISOLATED MODERATE AND STRONG CONVECTION IS NOTED FROM 03N TO 10N BETWEEN 88W AND 110W. SOUTHERLY FLOW S OF THE TROUGH...FROM 03N TO 06N BETWEEN 83W AND 93W...IS EXPECTED TO INCREASE TO 20 KT ON SAT NIGHT WITH SEAS BUILDING TO ABOUT 8 FT. ...DISCUSSION... AN UPPER LEVEL TROUGH DOMINATES THE NE PACIFIC WITH ITS MEAN AXIS EXTENDING S OVER THE DISCUSSION AREA ALONG 32N131W TO A BASE OVER THE DEEP TROPICS AT 12N125W. UPPER MOISTURE IS ROTATING THROUGH THE TROUGH N OF A LINE FROM 27N140W TO OVER SOUTHERN CALIFORNIA AND WESTERN ARIZONA. A LARGE BAND OF DRY AIR IS OBSERVED WITHIN 150 NM EITHER SIDE OF A LINE FROM 21N136W TO BEYOND 32N112W OVER EASTERN ARIZONA...AND OVER MOST OF NEW MEXICO AND TEXAS. A SMALL UPPER CYCLONE HAS CUT OFF OVER THE DEEP TROPICAL PACIFIC AT 06N125W WITH CONVECTION FLARING WITHIN 120 NM OVER ITS SW SEMICIRCLE. AN UPPER RIDGE EXTENDS E OVER THE AREA S OF 08N W OF 127W AND PROVIDED SUPPORT FOR CONVECTION ALONG THE ITCZ TO FLARE AS PREVIOUSLY DESCRIBED. THE ASSOCIATED DEBRIS MOISTURE IS NOW FANNING OUT OVER THE AREA FROM 07N TO 01S BETWEEN 130W AND 140W. AN UPPER ANTICYCLONE IS CENTERED NEAR 13N95W WITH AN UPPER RIDGE EXTENDING SW TO 10N123W...AND AN UPPER RIDGE ALSO EXTENDS E TO OVER NICARAGUA....AND A RIDGE ALSO EXTENDS NW TO A SHARP CREST AT 32N105W. DEBRIS MOISTURE FROM ITCZ CONVECTION BETWEEN 100W AND 122W IS ADVECTED N AND NE AROUND THE PERIPHERY OF THE UPPER RIDGE...WITHIN 150 NM EITHER SIDE OF A LINE FROM 13N117W TO 21N116W...AND THEN ACROSS THE RIDGE AXIS OVER NORTHERN OLD MEXICO...THEN EVAPORATING JUST AS THE MOISTURE REACHES SW TEXAS. A LARGE AREA OF ITCZ DEBRIS MOISTURE IS NOTED OVER THE DEEP TROPICS FROM 02N TO 12N E OF 115W...WITH SOME OF THE MOISTURE SPREADING NE ACROSS CENTRAL AMERICA AND OVER THE CARIBBEAN S OF 15N. AT THE LOW LEVELS A SURFACE RIDGE EXTENDS ALONG 30N140W TO 15N115W. THE GRADIENT HAS TIGHTENED WELL NE OF THE RIDGE... WITHIN 300 NM W OF THE BAJA CALIFORNIA PENINSULA...WITH SHIPS REPORTING NW 15 TO 20 KT WINDS AND SEAS 7 TO 10 FT. EXPECTING THIS AREA TO EXPAND N OVER THE AREA N OF 28N E OF 123W SAT NIGHT. CONDITIONS WILL BEGIN TO DIMINISH SUN. $$ NELSON