000 AXPZ20 KNHC 060345 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SUN APR 06 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 7N81W 6N86W 8N95W 5N101W 3N112W 4N130W 2N140W. ISOLATED MODERATE CONVECTION IS NOTED WITHIN 60 NM S OF THE AXIS BETWEEN 89W-96W AND BETWEEN 110W-114W. ...DISCUSSION... W OF 105W... TWO PROMINENT FEATURES DOMINATE THE REGION'S WEATHER PATTERN. THE FIRST IS A LARGE UPPER LEVEL CYCLONIC VORTEX LOCATED W OF THE AREA NEAR 25N147W MOVING SLOWLY NE OVER THE PAST 12-18 HOURS. THE SECOND IS A BROAD QUASI-STATIONARY MID/UPPER LEVEL ANTICYCLONE CENTERED NEAR 13N115W. A TROUGH EXTENDS SSE FROM THE UPPER LEVEL CYCLONIC THROUGH 18N144W 14N142W AND TO THE FAR WRN PART OF THE AREA NEAR 8N136W. SINCE THE UPPER LEVEL CYCLONIC VORTEX AND TROUGH ARE QUITE LARGE AND MOVING VERY LITTLE...THE PERSISTENT SW FLOW OF UPPER LEVEL WINDS AHEAD OF THE TROUGH INTO THE AREA DENOTES BROAD MID/UPPER LEVEL RIDGING ASSOCIATED WITH ANTICYCLONE AND COVERING THE AREA N OF 14N BETWEEN 129W-105W WITH A MEAN RIDGE AXIS THROUGH 32N125W SWD THROUGH 25N122W TO A LARGE QUASI-STATIONARY MID/UPPER LEVEL ANTICYCLONE ANCHORED NEAR 13N120W. MID/UPPER LEVEL MOISTURE ORIGINATING FROM THE DEEP CENTRAL TROPICAL PACIFIC IS BEING CHANNELED NEWD INTO THE DISCUSSION AREA ALONG THE NRN PERIPHERY OF THE RIDGE WITH A GENERAL TRAJECTORY TOWARDS BAJA CALIFORNIA AND CENTRAL MEXICO. CIMSS SATELLITE DERIVED WINDS WERE MAXING OUT TO 90 OVER THE AREA FROM 20N-25N E OF 117W. OVER THE DEEP TROPICS...MID-UPPER LEVEL ANTICYCLONE NOTED ABOVE HAS A RIDGE AXIS EXTENDING SE TO 5N105W. WATER VAPOR IMAGERY INDICATED STRONG SUBSIDENCE NEAR THE RIDGE GENERALLY FROM 5N TO 20N BETWEEN 100W AND 125W. SUBSIDENCE WAS INHIBITING CONVECTION ALONG THE ITCZ IN THE AREA. UPPER LEVEL DIFFLUENCE IS OCCURRING ON THE SW PERIPHERY OF THE ANTICYCLONE. NWP MODELS SUGGEST THAT THE ANTICYCLONE NEAR 13N120W WILL CHANGE LITTLE THROUGH THE MIDDLE PORTION OF NEXT WEEK...THEN BE REPLACED BY LOWERING HEIGHTS TOWARDS THE END OF THE WEEK. MID/UPPER LEVEL FLOW THEN BECOMES ZONAL OVER JUST ABOUT THIS ENTIRE AREA...EXCEPT FOR THE FAR NW CORNER WHERE IT WILL BE MORE OF NW FLOW DUE TO AND UPPER LEVEL HIGH THAT APPROACHES THE NW BOUNDARY BY WED. AT THE SURFACE...A STATIONARY 1012 MB LOW W OF THE REGION NEAR 26N147W WITH AN OCCLUDED FRONT NE TO 26N144W AND SE TO 25N142W WHERE IT BECOMES A COLD FRONT TO 15N145W. THE GRADIENT BETWEEN THIS FRONTAL SYSTEM AND 1028 MB HIGH PRESS NEAR 33N135W CONTINUES TO PRODUCE AN AREA OF SE WINDS OF 20 TO 25 KT FROM 20N-29N W OF 135W...WITH THE HIGHEST SEAS (8-10 FT IN RANGE) W OF 139W. THIS SYSTEM IS EXPECTED TO RETROGRADE OVER THE NEXT SEVERAL DAYS GRADUALLY PULLING THE AREA OF WINDS W OF THE AREA. HIGH RESOLUTION QUIKSCAT PASS FROM THIS MORNING REVEALED NW-N WINDS OF 20-25 KT N OF 25N E OF 121W TO THE COAST OF BAJA CALIFORNIA. THESE WINDS ARE EXPECTED TO LAST THROUGH SUN MORNING...THEN DIMINISH TO 20 KT SUN AFTERNOON AS THE PRES DIFFERENCE BETWEEN LOW PRES OVER THE SW UNITED STATED AND THE RIDGE WEAKENS SOME. A WEAK SURFACE TROUGH MOVING W 5-10 KT EXTENDS FROM 9N95W TO 6N96W. IT IS GENERATING ISOLATED SHOWERS AND TSTMS WITHIN 60-90 NM W OF ITS AXIS. A QUIKSCAT PASS FROM NEAR 0034 UTC THIS EVENING SHOWED RELATIVELY LIGHT WINDS ASSOCIATED WITH THE TROUGH. THE WILL CONTINUE TO TRACK W OVER THE NEXT 36-48 HRS BEFORE DISSIPATING. E OF 105W... THE TAIL END OF AN UPPER LEVEL TROUGH OVER THE CENTRAL CARIBBEAN SEA EXTENDS SWWD ACROSS HONDURAS AND NICARAGUA TO A BASE OVER THE FAR E PACIFIC NEAR 7N93W. DIFFLUENT FLOW E OF THE TROUGH IS AIDING CONVECTION ALONG THE ITCZ BETWEEN 86W AND 91W. WITH THE EXCEPTION OF THIS ITCZ CONVECTION...MODERATE TO STRONG UPPER LEVEL SUBSIDENCE PREVAILED OVER THE REMAINDER OF THE TROPICAL E PACIFIC E OF 100W. THE TROUGH IS FORECAST TO DAMPEN OUT OVER THE NRN CARIBBEAN BY WED OF NEXT WEEK. $$ AGUIRRE