000 AXPZ20 KNHC 120914 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC MON OCT 12 2009 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0900 UTC. ...SPECIAL FEATURE... AT 0900Z...TROPICAL STORM PATRICIA WAS LOCATED AT 18.6N 108.9W OR ABOUT 300 NM SOUTH-SOUTHEAST OF THE SOUTHERN TIP OF BAJA CALIFORNIA. MAX SUSTAINED WINDS 40 KT WITH GUSTS TO 50 KT. ESTIMATED CENTRAL PRESSURE IS 1001 MB. PATRICIA IS MOVING TO THE NORTH-NORTHWEST AT 6 KT...AND IS EXPECTED TO REACH THE SOUTHERN TIP OF BAJA CALIFORNIA ON TUESDAY BEFORE TURNING WEST. THE CENTER OF THE STORM IS ESTIMATED TO BE ON THE NE SIDE OF AN AREA OF STRONG CONVECTION...EXTENDING 180 NM TO THE SW OF THE LOW LEVEL CENTER. SCATTEROMETER DATA FROM 04Z INDICATED STRONG SOUTHERLY FLOW BETWEEN THE STORM CENTER AND THE MEXICAN COAST 16N TO 22N. PATRICIA IS FORECAST TO SLOWLY INTENSIFY THROUGH THE NEXT 48 HOURS BEFORE WEAKENING THEREAFTER. INTERESTS IN SOUTHERN BAJA CALIFORNIA SHOULD MONITOR THE DEVELOPMENT AND TRACK OF THIS STORM. SEE LATEST NHC FORECAST ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. ...TROPICAL WAVE... A TROPICAL WAVE IS ALONG 96W N OF 05N TO THE GULF OF TEHUANTEPEC IS MOVING W AT 10 TO 15 KT. THIS WAVE HAD BEEN COUPLED WITH AN UPPER LEVEL CYCLONE THAT HAS SINCE FILLED...AND THE CONVECTION HAS COMPLETELY DIMINISHED AS A RESULT. THE WAVE HAS SINCE WEAKENED...AND DOES NOT SHOW SIGNS OF BEING ORGANIZED. ANOTHER TROPICAL WAVE IS OVER THE FAR ERN PART OF THE AREA ALONG 80W N OF 5N MOVING W 10 TO 15 KT. IT IS ENHANCING ITCZ CONVECTION AT THE PRESENT TIME. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 07N78W TO 06N87W 12N98W TO 09N120W TO 13N130W TO 10N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM N OF AXIS E OF 85W. SCATTERED MODERATE WITHIN 60 NM EITHER SIDE OF AXIS BETWEEN 115W AND 125W. ...DISCUSSION... W OF 110W...A MID TO UPPER LEVEL TROUGH EXTENDING FROM 30N129W TO 21N140W WILL MOVE EASTWARD TODAY...N OF AN UPPER LEVEL RIDGE THAT EXTENDS EAST TO WEST FROM CENTRAL MEXICO ALONG ROUGHLY 17N. A SURFACE COLD FRONT ASSOCIATED WITH THE UPPER TROUGH EXTENDS FROM 30N135W TO 26N140W. A 1015 MB SURFACE HIGH CENTERED NEAR 25N130W WILL SHIFT EAST TOWARD BAJA AND WEAKEN TODAY AHEAD OF THE COLD FRONT...WHICH WILL REACH A POSITION FROM 31N127W TO 22N140W BY EARLY TUE. THE UPPER TROUGH SUPPORTING THE FRONT LIFTS OUT THROUGH THE SOUTHWEST U.S. TUE FOLLOWED BY ZONAL FLOW ALOFT SHIFTING SW. AS A RESULT THE FRONT STALLS AND BECOMES DIFFUSE TUE NIGHT THROUGH EARLY WED. RIDGING BUILDS IN THE WAKE OF THE TROUGH...ALLOWING THE SURFACE HIGH OFF BAJA TO BUILD...INCREASING NORTHERLY WINDS OFF THE BAJA COAST BETWEEN THE HIGH PRES AND T.S. PATRICIA S OF BAJA. WINDS N OF 28N WILL SHIFT SW AND INCREASE TUE...AHEAD OF A REINFORCING FRONT THAT WILL REMAIN N OF THE AREA. MEANWHILE...LONG PERIOD NW SWELL UP TO 8 FT WILL FOLLOW THE FIRST FRONT...FOLLOWED BY SLIGHTLY LARGER NW SWELL RELATED TO THE REINFORCING FRONT PUSHING S OF 30N. FURTHER SOUTH...MODERATE TO FRESH SW FLOW INTO THE ITCZ WILL ENHANCE A WEAK CYCLONIC CIRCULATION EXPECTED TO FORM ALONG THE ITCZ NEAR 130W. TRADES WILL REMAIN LIGHT N OF THIS FEATURE AS SUBTROPICAL RIDGE REMAINS WEAK...BUT SOME INCREASE IN CONVECTION ALONG THE ITCZ IS POSSIBLE W OF 130W. E OF 110W...FRESH TO STRONG TRADE WIND FLOW ACROSS THE SW CARIBBEAN WILL CONTINUE TO FILTER THROUGH COSTA RICA AND INTO THE GULF OF PAPAGAYO. FURTHER SOUTH...INCREASED SW FLOW S OF THE ITCZ POSSIBLY IN RELATION TO THE TROPICAL WAVE NOW ALONG 80W...WILL HELP DEVELOP A BROAD LOW PRES AREA ALONG THE ITCZ NEAR 90W BY EARLY WED. $$ CHRISTENSEN