000 AXPZ20 KNHC 290926 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC TUE MAY 29 2007 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 0515 UTC. ...SPECIAL FEATURES... TROPICAL STORM ALVIN AT 12.5N 114.0W AT 0900 UTC WITH ESTIMATED CENTRAL PRES OF 1004 MB MOVING W SW OR 250 DEG AT 5 KT. NUMEROUS MODERATE TO STRONG CONVECTION NOTED WITHIN 30 NM N SEMICIRCLE AND WITHIN 75 NM S SEMICIRCLE OF CENTER. SCATTERED MODERATE ISOLATED STRONG IS NOTED IN BANDS ELSEWHERE WITHIN 150 NM OVER NW SEMICIRCLE AND WITHIN 120 NM OVER SE SEMICIRCLE. FAVORABLE WATER TEMPERATURES SUPPORT FOR ALVIN TO STRENGTHEN SLIGHTLY OVER THE NEXT FEW DAYS. A LARGE AREA OF LOW PRESSURE SOUTH OF THE GULF OF TEHUANTEPEC HAS BECOME BETTER ORGANIZED AND MAY FORM INTO A TROPICAL DEPRESSION LATER TODAY. ...ITCZ... INTERTROPICAL CONVERGENCE ZONE AXIS 11N85W 9N100W 8N115W 7N140W. SCATTERED MODERATE 130 NM WIDE 122W TO 132W. DISCUSSION... AN UPPER EXTENDS THRIUGH 32N131W TO 20N140W. A 360 NM WIDE BAND OF MOISTUE SE OF THE TROUGH IS MOVING RAPIDLY TOWARDS BAJA CALIFORNIA. A BROAD RIDGE WITH CENTER NER 15N115W DOMINATES THE REST OF THE AREA W OF 100W. DRY UPPER AIR IS TRAPPED UNDER THE RIDGE. UPPER DIFFLUENCE IS ENHANCING ALONG 13N BETWEEN 94W AND 116W. SOME OF THE RESULTANT DEBRIS MOISTURE IS ADVECTED S ACROSS THE EQUATOR BETWEEN 109W AND 118W. SOME OF THE MOISTURE SPREADS N BUT EVAPORATES IN THE UPPER DRY AIR ALONG 21N. A RIDGE EXTENDING E ACROSS CENTRAL AMERICA TO A SHARP CREST NEAR 15N83W. AN OTHER UPPER ANTICYCLONE IS OVER THE E CARIBBEAN NEAR 12N108W WITH A RIDGE W TO NEAR 12N74W. A BROAD TROUGH LIES BETWEEN THESE UPPER RIDGES OVER THE CENTRAL CARIBBEAN EXTENDING S INTO THE E PAC NEAR 8N78W. SCATTERED CONVECTION WAS ENHANCED MON AFTERNOON OVER THE SW CARIBBEAN AND THE ASSOCIATED DEBRIS MOISTURE IS ADVECTED S OVER THE E PAC S OF 12N E OF 88W. AT THE SURFACE... RIDGE EXTENDS INTO DISCUSSION AREA ALONG 32N141W 20N110W. A LOW LEVEL TROUGH IS EMBEDDED IN THE ITCZ NEAR 8N126W. $$ FET