000 AXPZ20 KNHC 050324 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT APR 05 2008 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. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 9N84W 4N102W 2N115W 3N130W 4N140W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 120 NM S OF THE AXIS BETWEEN 121W-126W. ...DISCUSSION... UPPER LEVEL W-NW FLOW IS PRESENT OVER THE NE SECTOR OF THE AREA N OF 20N E OF 120W IN THE WAKE OF A MID/UPPER LEVEL TROUGH THAT IS PRESENTLY OVER THE CENTRAL UNITED STATES. AT THE SURFACE ...NW-N WINDS TO 20 KT WITH SEAS TO 8 FT ARE BEING NOTED TO THE N OF 19N E OF 121W INCLUDING THE GULF OF CALIFORNIA. THESE WINDS ARE EXPECTED TO CONTINUE OVER THE NEXT FEW DAYS AS THE PRES DIFFERENCE BETWEEN LOW PRES OVER THE SW UNITED STATED AND THE RIDGE ALLOW SUSTAIN A GRADIENT ADEQUATE TO SUPPORT THESE WINDS. A MID/UPPER LEVEL RIDGE AXIS EXTENDS FROM 32N122W S THROUGH 25N122W TO A LARGE QUASI-STATIONARY MID/UPPER LEVEL ANTICYCLONE ANCHORED NEAR 13N120W. THE RIDGE HAS AMPLIFIED DURING THE PAST 36-48 HRS AS A RESULT OF THE AMPLIFICATION OF A RATHER BROAD TROUGH THAT IS W OF THE REGION WITH A MEAN AXIS ALONG 144W. MID/UPPER LEVEL MOISTURE ORIGINATING FROM THE DEEP CENTRAL TROPICAL PACIFIC IS BEING CHANNELED NEWD INTO THE AREA UP AND AROUND THE NRN PERIPHERY OF THE RIDGE WITH A GENERAL TRAJECTORY AIMED TOWARDS BAJA CALIFORNIA AND CENTRAL MEXICO. THE TROUGH IS PART OF A LARGE CYCLONIC VORTEX W OF THE AREA MOVING SLOWLY S NEAR 25N149W. THE ASSOCIATED SURFACE SYSTEM CONSISTS OF A STATIONARY 1015 MB LOW W OF THE REGION NEAR 25N152W WITH A DYING OCCLUDED FRONT TO 27N148.5W AND TO 24N146W ...WHERE IT BECOMES A WEAKENING STATIONARY FRONT TO SE OF THE HAWAIIAN ISLANDS. BECAUSE OF THE FACT THAT THIS SYSTEM IS NOT MOVING MUCH AT ALL...AND IS ONLY EXPECTED TO RETROGRADE SLOWLY WWD OVER THE NEXT DAYS THE TYPICAL PERSISTENT HIGH PRES THAT EXETNDS SE INTO THE AREA WILL NOT BE AS PRONOUNCED ALLOWING FOR THE TRADE WIND BELT ZONE TO CONTINUES TO BE RATHER SMALL IN AREAL COVERAGE AND WEAK IN WIND SPEEDS COVERING THE POINTS FROM NEAR 8N TO 19N AND W OF 120W WITH SEAS THERE UP TO 8 FT. HOWEVER ...SE WINDS N OF 17N AND W OF 135W WILL BE 20 KT WITH SEAS TO 9 FT IN NW SWELL AS PRES GRADIENT THERE WILL BE STRONGER DUE TO THE CLOSER PROXIMITY OF THE LOW AND FRONT TO THE SURFACE HIGH CENTER OF 1031 MB N OF THE AREA NEAR 35N136W. THESE WINDS WILL INCREASE TO ABOUT 20-25 KT BY SAT EVENING AS THE HIGH MOVES S AND SW ALLOWING FOR THE PRES GRADIENT TO INCREASE FURTHER...BUT THEN DECREASE LATE ON SUN AS THE LOW AND FRONT PULL FURTHER TO THE W AND WEAKEN. THE CYCLONIC VORTEX IS FORECAST TO DROP S THROUGH THE NEXT 48 HRS...THEN WEAKEN AND POSSIBLY OPEN UP INTO A TROUGH MON AS IT TRACKS W TO N OF THE HAWAIIAN ISLANDS... AND IS REPLACED BY HIGH PRES. THE ANTICYCLONE MENTIONED ABOVE NEAR 13N120W ALSO HAS A RIDGE EXTENDING SE TO 5N105W. WATER VAPOR IMAGERY CONTINUES TO INDICATE STRONG SUBSIDENCE UNDERNEATH THE RIDGE ACROSS THIS AREA...INHIBITING NOT ONLY ANY CONVECTION BUT NEARLY ALL CLOUD COVER. ONLY ISOLATED SHOWERS AND TSTMS ARE NOTED FROM 6N-13N BETWEEN 89W-98W MAINLY ASSOCIATED WITH THE ITCZ...AND WITH A SURFACE TROUGH SLOWLY MOVING W FROM 8N98W TO 3N102W. A COL REGION IS NOTED SW OF THE ANTICYCLONE NEAR 6N135W...WHICH IS S OF A POINT WHERE THE UPPER LEVEL FLOW TRANSITIONS FROM CYCLONIC TO ANTICYCLONIC TO ITS N AND NE. UPPER LEVEL DIFFLUENCE OCCURRING ON THE SW PERIPHERY OF THE ANTICYCLONE IS ENHANCING ITCZ CONVECTION BETWEEN 121W-126W. A WEAK SURFACE TROUGH MOVING W 10-15 KT IS ALONG 130W FROM 2N-5N AND IS CURRENTLY LOSING ITS SHOWER AND TSTMS ACTIVITY BUT SHOULD REDEVELOP AGAIN OVER THE NEXT SEVERAL HRS AS IT REMAINS UNDER THE DIFFLUENT FLOW. TO THE NE OF THE ANTICYCLONE...A JET STREAM BRANCH IS LOCATED OVER THE NRN PERIPHERY OF THE ANTICYCLONE FROM 24N122W EXTENDING ESE TO ACROSS SRN BAJA CALIFORNIA AND CENTRAL MEXICO. MAXIMUM WINDS WITH THE JET ARE IN THE RANGE OF 60-70 KT FOUND BETWEEN SRN BAJA AND THE COAST OF CENTRAL MEXICO. THE TAIL END OF AN UPPER LEVEL TROUGH OVER THE CENTRAL CARIBBEAN SEA EXTENDS SW TO ACROSS HONDURAS AND NICARAGUA AND TO THE FAR E PACIFIC WATERS NEAR 8N88W. IT IS AIDING CONVECTION ALONG THE ITCZ NEAR THE SURFACE TROUGH ALONG 8N93W 3N102W. NWP MODELS CONTINUE TO FORECAST THE ANTICYCLONE NEAR 13N120W TO MOVE WWD WITHIN THE NEXT FEW DAYS AS HEIGHTS LOWER OVER MEXICO AND THE GULF OF MEXICO...WHILE THE TROUGH LIFTS NE AND DAMPENS OUT OVER THE NRN CARIBBEAN. MID/UPPER LEVEL FLOW THEN BECOMES ZONAL OVER JUST ABOUT THE ENTIRE DISCUSSION AREA...EXCEPT FOR THE FAR NW CORNER WHERE IT WILL BE UNDER THE INFLUENCE OF THE UPPER LEVEL LOW NEARING THAT PORTION OF THE AREA. GAP WINDS ARE EXPECTED TO BE N0N-EXISTENT THROUGH NEXT WEEK AS WEAK PRES PATTERN SETS UP OVER THE FAR ERN PORTION OF THE REGION INCLUDING THE CENTRAL AMERICAN COAST AND SE SECTION OF MEXICO. $$ AGUIRRE