000 AXPZ20 KNHC 242152 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT MAY 24 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2145 UTC. ...SPECIAL FEATURE... HURRICANE AMANDA IS CENTERED NEAR 11.4N 110.3W...OR ABOUT 660 MILES SW OF MANZANILLO MEXICO AT 2100 UTC MAY 24. MINIMUM CENTRAL PRESSURE IS 987 MB. AMANDA IS MOVING WNW...OR 290 DEG... AT 04 KT. MAXIMUM SUSTAINED WINDS ARE 70 KT WITH GUSTS TO 85 KT. AMANDA NOW HAS 10 NM DIAMETER EYE WITH NUMEROUS STRONG CONVECTION OBSERVED WITHIN 60 NM OVER THE W SEMICIRCLE. SCATTERED MODERATE TO STRONG CONVECTION IS NOTED ELSEWHERE WITHIN 150 NM EITHER SIDE OF A LINE FROM 15N110W TO 09N110W...WITH A STRONG OUTER BAND WITHIN 30 NM EITHER SIDE OF A LINE FROM 10N112W TO 13N112W. AMANDA IS FORECAST TO GRADUALLY STRENGTHEN TO A 100 KT MAJOR HURRICANE ON SUN NIGHT NEAR 12.6N 111.2W. THEREAFTER...AMANDA WILL BEGIN TO ENCOUNTER SOUTHERLY SHEAR AND IS EXPECTED TO WEAKEN A TROPICAL STORM ON WED NEAR 16N111.5W. SEE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP1/WTPZ21 KNHC FOR MORE DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS W OFF THE COAST OF COLOMBIA AT 08N78W...THEN TURNS NW ACROSS THE GULF OF PANAMA AND INTERIOR WESTERN PANAMA EXITING THE COAST OF COSTA RICA AT 09N84W. THE TROUGH AXIS CONTINUES SW TO 08N93W THEN WESTWARD TO 08N104W 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 06N112W AND CONTINUES W TO 07N122W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ. THE ITCZ THEN WIGGLES WESTWARD TO BEYOND 05N140W. A LARGE AREA OF UPPER DIFFLUENCE IS ENHANCING SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 150 NM EITHER SIDE OF A LINE FROM 07N81W TO 04N104W...AND ALSO WITHIN 120 NM EITHER SIDE OF A LINE FROM 09N87W TO 14N99W. ISOLATED MODERATE TO STRONG CONVECTION IS OBSERVED ELSEWHERE TO THE N OF 02N E OF 107W. SCATTERED MODERATE CONVECTION IS OBSERVED ALONG THE ITCZ WITHIN 120 NM EITHER SIDE OF A LINE FROM 04N135W TO 09N140W. ...DISCUSSION... AN UPPER ANTICYCLONE IS CENTERED NEAR 33N130W WITH DRY UPPER AIR INDICATED WITHIN ITS ENVELOPE AND COVERING THE DISCUSSION AREA N OF 26N TO THE W OF 125W. AN UPPER CYCLONE HAS BEEN QUASI- STATIONARY NEAR 22N134W FOR THE PAST DAY WITH AN UPPER TROUGH EXTENDING SE TO A BASE OVER THE TROPICS AT 12N130W. A SMALL UPPER ANTICYCLONE IS OVER THE DEEP TROPICS AT 04N134W...AND IS ENHANCING 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 21N116W. THIS MOISTURE WILL LIKELY MERGE WITH THE DEBRIS MOISTURE FROM HURRICANE AMANDA LATER TONIGHT. AN UPPER CYCLONE IS CENTERED OVER EASTERN ARIZONA WITH AN UPPER TROUGH EXTENDING SSW TO A BASE OVER THE PACIFIC AT 23N116W. 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 10N127W. DEBRIS MOISTURE FROM AMANDA...AND OTHER CONVECTION UNDER THE UPPER RIDGE BETWEEN 90-112W...IS ADVECTED NE ALONG THE W PERIPHERY OF THE ANTICYCLONE AND ACROSS CENTRAL MEXICO FROM 15-25N...AND CONTINUES NE ACROSS THE GULF OF MEXICO. 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 80-93W. A 1026 MB SURFACE HIGH IS CENTERED NEAR 33N136W WITH A RIDGE EXTENDING SE TO 17N105W PER LATEST SCATTEROMETER WINDS. 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 ON SUN NIGHT...INCREASING THE NW-N WINDS TO 15-20 KT AND DRIVING A TONGUE OF 7-9 FT SEAS INTO THE DISCUSSION WATERS N OF 25N BETWEEN 120-132W ON MON AND TUE. THE N WINDS ARE EXPECTED TO INCREASE TO 20-25 KT ACROSS THE WATERS N OF 30N ON WED...WITH SEAS BUILDING 8-12 FT IN MIXED N AND S SWELL ACROSS THE WATERS N OF 25N W OF 117W. $$ NELSON