000 AXPZ20 KNHC 292205 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC TUE MAY 29 2007 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2145 UTC. ...SPECIAL FEATURES... TROPICAL STORM ALVIN IS CENTERED NEAR 12.6N 114.0W AT 29/2100 UTC MOVING W OR 265 DEG AT 3 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. NUMEROUS MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 30 NM OVER NW SEMICIRCLE AND WITHIN 90 NM SE SEMICIRCLE 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 97.7W AT 29/2100 UTC AND IS NEARLY STATIONARY. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB. MAXIMUM SUSTAINED WIND SPEED IS 30 KT WITH GUSTS TO 40 KT. NUMEROUS STRONG CONVECTION IS OBSERVED WITHIN 30 NM OVER THE E SEMICIRCLE. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS NOTED ELSEWHERE WITHIN 90 NM OVER THE NW SEMICIRCLE AND WITHIN 150 NM OVER THE SE SEMICIRCLE. AN UPPER TROUGH CURRENTLY EXTENDING SE FROM EASTERN OLD MEXICO TO THE BAY OF CAMPECHE IS EXPECTED TO DIG A LITTLE FURTHER S WHILE AND UPPER RIDGE OVER THE PAC ALONG 120W SHIFTS E OVER THE BAJA PENINSULA. THIS SHOULD EFFECTIVELY MOVE THE DEPRESSION SLOWLY AWAY FROM THE MEXICAN COAST AND THEN 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 13N98W 7N115W 8N140W. EXCEPT FOR CONVECTION DESCRIBED WITH THE TROPICAL CYCLONES ABOVE... SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED ELSEWHERE WITHIN 150 NM EITHER SIDE OF LINE 11.5N86.5W 13N103W AND ALSO WITHIN 30 NM OF LINE 10N100W 10N109W AND ADDITIONALLY WITHIN 90 NM OF LINE 7N115W 7N131W. DISCUSSION... AN UPPER ANTICYCLONE IS CENTERED AT 15N111W. A RIDGE EXTENDS SW OVER TROPICAL STORM ALVIN TO A SHARP CREST OVER THE ITCZ NEAR 7N142W. ASSOCIATED UPPER DIFFLUENCE IS ENHANCING CONVECTION ASSOCIATED WITH ALVIN AND ALONG THE ITCZ BETWEEN 119W AND 132W. THE RESULTANT DEBRIS MOISTURE IS SPREADING N TO ALONG 12N AT THE MOMENT. AN UPPER RIDGE ALSO EXTENDS N CRESTING ALONG POINTS 15N140W 31N120W 23N109W. AN UPPER CYCLONE HAS DEVELOPED NW OF THE RIDGE NEAR 30N130W AND IS MOVING N WHILE TRAILING AN UPPER TROUGH SW TO BEYOND 19N140W. THIS TROUGH IS ACCOMPANIED BY VERY DRY UPPER AIR...BUT SOME UPPER MOISTURE IS ALSO SPREADING EASTWARD OVER THE DISCUSSION AREA TO THE N OF 20N AND W OF 135W. AN UPPER MOISTURE PLUME IS SQUEEZED BETWEEN THE TROUGH AND THE RIDGE ROUGHLY ALONG HE W PERIPHERY OF THE RIDGE...WITHIN 150 NM EITHER SIDE OF LINE 12N140W 22N128W 27N116W. 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 101W. AN UPPER RIDGE EXTENDS E FROM THE ANTICYCLONE AT 15N11W OVER THE DEVELOPING TROPICAL DEPRESSION TO A CREST OVER THE SW CARIBBEAN AT 12N81W. ASSOCIATED UPPER DIFFLUENCE IS ENHANCING CONVECTION NEAR THE DEPRESSION AND ALONG THE ITCZ AS FAR E AS 80W. 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