000 AXPZ20 KNHC 300327 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC WED MAY 30 2007 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 0315 UTC. ...SPECIAL FEATURES... TROPICAL STORM ALVIN IS CENTERED NEAR 12.8N 114.3W AT 30/0300 UTC MOVING W OR 270 DEG AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. NUMEROUS MODERATE ISOLATED STRONG WITHIN 60 NM OF CENTER. SOME INTENSIFICATION IS EXPECTED OVER THE NEXT DAY OR SO AS THE OCEANIC AND ATMOSPHERIC ENVIRONMENT REMAIN FAVORABLE. TROPICAL DEPRESSION TWO-E...IS CENTERED NEAR 14.2N 97.5W AT 30/0300 UTC AND IS NEARLY STATIONARY. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1007 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. NUMEROUS MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 90 NM SE SEMICIRCLE. GRADUAL INTENSIFICATION TO A HURRICANE IS EXPECTED. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 11N86W 13N97W 10N105W 13N114W 6N120W 7N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 90 NM EITHER SIDE OF LINE 9N100W 12N106W AND WITHIN 30 NM 7N118W AND 7N126.5W. ...DISCUSSION... AN UPPER ANTICYCLONE IS CENTERED AT 15N109W. A RIDGE EXTENDS SW OVER TROPICAL STORM ALVIN TO A SHARP CREST OVER THE ITCZ NEAR 7N143W. ASSOCIATED UPPER DIFFLUENCE IS ENHANCING CONVECTION ASSOCIATED WITH ALVIN AND ALONG THE ITCZ BETWEEN 117W AND 129W. THE RESULTANT DEBRIS MOISTURE IS SPREADING N TO ALONG 16N AT THE MOMENT. AN UPPER RIDGE ALSO EXTENDS N CRESTING ALONG POINTS 22N131W 31N118W 23N109W. AN UPPER CYCLONE HAS DEVELOPED NW OF THE RIDGE NEAR 31N127W AND IS MOVING N WHILE TRAILING AN UPPER TROUGH SW TO BEYOND 18N140W. THIS TROUGH IS ACCOMPANIED BY VERY DRY UPPER AIR...BUT SOME UPPER MOISTURE IS ALSO SPREADING EASTWARD OVER THE DISCUSSION AREA TO THE W OF LINE 19N140W 26N132W 32N133W. AN UPPER MOISTURE PLUME IS SQUEEZED BETWEEN THE TROUGH AND THE RIDGE ROUGHLY ALONG THE W PERIPHERY OF THE RIDGE...WITHIN 150 NM EITHER SIDE OF LINE 12N140W 21N130W 28N114W. OTHERWISE DRY UPPER AIR IS TRAPPED UNDER THE RIDGE...AND EFFECTIVELY DRIES OUT THE DEBRIS MOISTURE FROM BOTH TROPICAL CYCLONES ALONG 18N BETWEEN 118W AND 100W. AN UPPER RIDGE EXTENDS E FROM THE ANTICYCLONE AT 15N109W OVER THE DEVELOPING TROPICAL DEPRESSION TO A CREST OVER THE SW CARIBBEAN AT 16N80W. ASSOCIATED UPPER DIFFLUENCE IS ENHANCING CONVECTION NEAR THE DEPRESSION AND ALONG THE ITCZ AS FAR E AS 71W. SOME OF THE ASSOCIATED DEBRIS MOISTURE IS ADVECTED S OVER THE E PAC WHILE SOME IS ADVECTED NE OVER CENTRAL AMERICA. AT THE SURFACE... RIDGE EXTENDS INTO DISCUSSION AREA ALONG 34N133W 19N105W. $$ NELSON