000 AXPZ20 KNHC 112144 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT APR 11 2009 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2130 UTC. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 6N78W 8N90W 8N100W 7N110W 3N121W 3N140W. SCATTERED MODERATE CONVECTION EXISTS FROM 4N-6N BETWEEN 90W-92W. ...DISCUSSION... LATEST SATELLITE WATER VAPOR IMAGERY SHOWS THE STRONG SHORTWAVE TROUGH THAT YESTERDAY PUSHED A TROUGH THROUGH THE NE PORTION OF THE AREA FOLLOWED BY STRONG NW WINDS HAS NOW MOVED INLAND THE WRN U.S. ITS SRN EXTENSION EXTENDS SSW TO 24N112W TO 19N118W TO 14N124W TO 7N134W. CONFLUENT FLOW INTO THE BACK SIDE OF THE TROUGH IS RESULTING IN AN AREA OF MODERATE SUBSIDENCE AND RATHER STABLE CONDITIONS FROM 17N-28N AND E OF 131W. SCATTERED HIGH CLOUDS E OF THE TROUGH N OF 18N ARE MOVING NE ACROSS NRN MEXICO. THE TROUGH WILL CONTINUE TO MOVE FURTHER INLAND THROUGH SUN. A PARTIAL QUIKSCAT PASS FROM JUST PAST 1300 UTC MORNING SHOWED NW WINDS OF 20-25 KT N OF ABOUT 26N E OF 125W WITH SEAS 8-12 FT. ELSEWHERE...N OF 23N BETWEEN 115W AND 130W WINDS ARE LESS THAN 20 KT WITH SEAS 8 TO 11 FT IN NW SWELL. SEAS WILL WITHIN THIS ARA WILL SLOWLY SUBSIDE THROUGH THE NEXT 48 HRS. TO THE W OF THE TROUGH...A LONGWAVE RIDGE IS JUST CROSSING 140W. UPPER LEVEL MOISTURE FROM THE DEEP TROPICAL CENTRAL PACIFIC IS RIDING UP ACROSS THE RIDGE AND SPILLING SE INTO THE FAR WRN PORTION OF THE AREA N OF 13N W OF 131W. TO THE E AND SE OF THE TROUGH...BROAD UPPER RIDGING WITH A NEARLY STATIONARY ANTICYCLONE MOVING WSW NEAR 6.5N101.5W CONTINUES TO MAINTAIN RATHER DRY AND STABLE CONDITIONS OVER THE SE PORTION OF THE AREA. TO THE SW OF THE TROUGH...THE ERN PERIPHERY OF BROAD MID/UPPER RIDGING OVER THE S/CENTRAL PACIFIC EXTENDS E INTO THE AREA TO NEAR 136W. A SMALL UPPER LEVEL CYCLONIC CIRCULATION NEAR 1N128W MOVING WSW 15 KT IS PRODUCING ISOLATED WEAK CONVECTION WITHIN 45 NM OF LINE 5N123W TO 3N126.5W. AT THE SURFACE...A STATIONARY 1029 MB HIGH CENTER IS NEAR 32N125W WITH A RIDGE EXTENDING SE THROUGH 27N125W TO 22N117W TO 17N107W. HIGH PRES COVERS THE AREA N OF 14N W OF 107W. LATEST VISIBLE SATELLITE IMAGERY SHOWS A WEAK TROUGH DISPLAYING SOMEWHAT OF AN INVERTED-V SHAPE PATTERN OVER THE LOCATION FROM 12N120W TO 6N124.5W. ISOLATED SHOWERS AND SPORADIC SMALL TSTM CELLS ARE WITHIN 30 NM OF THE TROUGH. ANOTHER WEAK TROUGH EXTENDS ALONG 135W S OF 6N MOVING W ABOUT 15 KT. ALTHOUGH THIS TROUGH APPEARED MORE DISTINCTLY DEFINED IN SATELLITE IMAGERY FROM THE PREVIOUS 24 HRS...IT HAS SINCE THEN LOST ASSOCIATED CLOUDINESS AND SMALL VORTICITY MAXIMUM NOTED 24 HRS. IT IS JUST CLOSE ENOUGH TO THE SRN TIP OF THE UPPER TROUGH DESCRIBED ABOVE TO ALLOW FOR SHORT-LIVED ISOLATED TSTMS TO DEVELOP WITHIN 180 NM ON EITHER SIDE OF ITS AXIS. THE COMBINATION OF THESE TROUGHS WITH THE SURFACE RIDGE TO THE N IS RESULTING IN NE TRADES OF 20 KT FROM 6N TO 21N W OF 120W WITH SEAS 8-10 FT PRIMARILY IN NE SWELL. THESE MARINE CONDITIONS ARE EXPECTED TO EXPAND E TO 118W IN 24 HRS...THEN DECREASE IN AREAL COVERAGE TO W OF 130W IN 48 HRS WITH SEAS STILL AROUND THE 8-10 FT RANGE IN NE SWELL. NW WINDS OF 20 KT ARE OVER AN AREA BOUNDED FROM 17N-21N E OF 108W TO THE COAST OF MEXICO WITH SEAS LESS THAN 8 FT. THIS AREA WILL EXPAND N TO 23N IN 24 HRS...THEN DIMINISHING IN 48 HRS. PATCHES OF CELLULAR SHAPE MOSTLY BROKEN STRATOCUMULUS CLOUDS MOVING SW TO W WITH POSSIBLE ISOLATED SHOWERS ARE PRESENT N OF 19N...AND ARE BEING STEERED BY THE GENERAL SYNOPTIC WIND FLOW AROUND THE RIDGE THAT EXTENDS INTO THE REGION DESCRIBED ABOVE. $$ AGUIRRE