000 AXPZ20 KNHC 251003 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN MAY 25 2014 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0945 UTC. ...SPECIAL FEATURE... HURRICANE AMANDA IS CENTERED NEAR 11.7N 110.9W...OR ABOUT 670 MILES SW OF MANZANILLO MEXICO AT 0900 UTC MAY 25. THE MINIMUM PRES OF THE INTENSIFYING CYCLONE HAS DROPPED TO 946 MB. AMANDA IS MOVING WNW...OR 295 DEG... AT 04 KT. MAXIMUM SUSTAINED WINDS HAVE INCREASED TO 120 KT WITH GUSTS TO 140 KT. AMANDA NOW HAS 15 NM DIAMETER EYE WITH NUMEROUS STRONG CONVECTION OBSERVED WITHIN 120 NM OF THE CENTER IN THE NE QUADRANT...WITHIN 150 NM IN THE SE QUADRANT AND WITHIN 45 NM IN THE W SEMICIRCLE. SCATTERED MODERATE TO STRONG CONVECTION IS NOTED ELSEWHERE IN OUTER BANDS WITHIN 45 NM OF LINE FROM 11N113W TO 09N111W...AND ALSO FROM 12N TO 14N BETWEEN 112W AND 113W. AMANDA IS FORECAST TO STRENGTHEN SLIGHTLY THIS AFTERNOON BEFORE ITS BEGINS TO ENCOUNTER SOUTHERLY SHEAR. THIS WILL CAUSE IT TO UNDERGO WEAKENING BEGINNING TONIGHT...AND EVENTUALLY WEAKEN TO A MINIMAL HURRICANE BY LATE TUE NIGHT NEAR 15.6N 111.6W PER LATEST NHC ADVISORY. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS OFF THE COAST OF CARIBBEAN COAST OF COLOMBIA AT 06N77W NW TO ACROSS WRN COST RICA AT 09N84W. THE TROUGH CONTINUES 10N90W TO 10N95W TO LOW PRES 1008 MB AT 10N98W ...THEN TURNS NW TO 11N103W WHERE THE MONSOON TROUGH LOSES IDENTITY IN THE BROAD CYCLONIC CIRCULATION ASSOCIATED WITH STRENGTHENING HURRICANE AMANDA. THE MONSOON TROUGH THEN RESUMES SW OF AMANDA NEAR 08N114W TO 08N124W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ. THE ITCZ THEN EXTENDS TO 05N133W TO 05N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS S OF THE EASTERN SEGMENT OF THE MONSOON TROUGH WITHIN 30 NM OF A LINE FROM 04N79W TO 05N85W TO 07N92W. SIMILAR ACTIVITY IS ALONG THE TROUGH BETWEEN 97W AND 101W. SCATTERED MODERATE CONVECTION IS NOTED S OF THE TROUGH FROM 02N TO 08N BETWEEN 92W AND 100W...AND ALSO WITHIN 60 NM OF THE ITCZ BETWEEN 129W AND 136W. ...DISCUSSION... AN UPPER ANTICYCLONE IS CENTERED NEAR 31N130W WITH DRY UPPER AIR INDICATED WITHIN ITS ENVELOPE AND COVERING THE DISCUSSION AREA N OF 26N TO THE W OF 123W. AN UPPER CYCLONE IS SEEN AT 22N128W WITH AN UPPER TROUGH EXTENDING SE TO NEAR 10N119W. A SMALL UPPER ANTICYCLONE IS OVER THE DEEP TROPICS AT 04N134W...AND IS ENHANCING ONLY SCATTERED MODERATE CONVECTION ALONG THE ITCZ AS PREVIOUSLY DESCRIBED. DEBRIS MOISTURE FROM THIS CONVECTION SPREADS N AND MERGES WITH A DENSE MOISTURE... ORIGINATING FROM ITCZ CONVECTION W OF THE AREA...AND CONCENTRATES INTO A TROPICAL PLUM THAT CONTINUES NE WITHIN 120 NM EITHER SIDE OF A LINE FROM 13N133W TO 22N113W. THE LEADING PORTION OF THIS MOISTURE PLUME IS ALREADY MERGING WITH THE DEBRIS MOISTURE FROM HURRICANE AMANDA JUST TO THE S AND SW OF THE SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA. AN UPPER CYCLONE IS CENTERED OVER WESTERN NEW MEXICO WITH AN UPPER TROUGH EXTENDING SSW TO A BASE OVER THE PACIFIC AT 24N121W. UPPER MOISTURE IS ROTATING CYCLONICALLY AROUND THE WESTERN SEMICIRCLE OF THE CYCLONE AND IS NOW SPREADING S ACROSS THE NORTHERN BAJA CALIFORNIA PENINSULA. AN UPPER ANTICYCLONE IS E OF HURRICANE AMANDA NEAR 13N102W WITH AN UPPER RIDGE EXTENDING SW ACROSS THE HURRICANE TO A SHARP CREST AT 10N123W. DEBRIS MOISTURE FROM AMANDA...AND OTHER CONVECTION UNDER THE UPPER RIDGE BETWEEN 89W-116W...IS ADVECTED NE ALONG THE W PERIPHERY OF THE ANTICYCLONE AND ACROSS CENTRAL MEXICO FROM 13N-25N...AND CONTINUES WELL TO THE NE OF THE AREA. AN UPPER TROUGH CONTINUES SW ACROSS THE WESTERN CARIBBEAN TO A BASE OVER PANAMA. CONVECTION IS ENHANCED ALONG THE BASE OF THIS UPPER TROUGH AND ALONG THE LOWER LEVEL MONSOON TROUGH AS PREVIOUSLY MENTIONED. ALTHOUGH SOME OF THE DEBRIS MOISTURE IS ADVECTED NE ACROSS EXTREME NW COLOMBIA...MOST OF THE DEBRIS MOISTURE IS ADVECTED S...CURRENTLY REACHING THE EQUATOR BETWEEN 87W-109W. A 1028 MB SURFACE HIGH IS CENTERED NEAR 33N137W WITH A RIDGE EXTENDING SE TO 25N125W TO NEAR 20N116W AS ANALYZED IN THE 06 UTC ANALYSIS. ANTICYCLONIC SURFACE WINDS ARE FORECAST AT 10-15 KT AROUND THE SOUTHERN PERIPHERY OF THIS RIDGE THROUGH THE MIDDLE OF NEXT WEEK...WITH ASSOCIATED SEAS OF 5-7 FT. THE GRADIENT IS EXPECTED TO TIGHTEN NE OF THE RIDGE TONIGHT LEADING TO INCREASING THE NW-N WINDS TO 15-20 KT AND DRIVING A SWATH OF 7-9 FT SEAS INTO THE DISCUSSION WATERS N OF 25N BETWEEN 121W AND 129W ON MON AND TUE. $$ AGUIRRE