000 AXPZ20 KNHC 101522 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC SUN APR 10 2011 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE AXIS WAS ANALYZED FROM 07N78W TO 08N95W THEN RESUMES FROM 06N99W TO 08N123W THEN RESUMES FROM 03N129W TO 00N133W. SCATTERED MODERATE TO STRONG CONVECTION WAS WITHIN 120 NM N OF THE AXIS E OF 80W AND WITHIN 120 NM S OF THE AXIS BETWEEN 80W AND 84W. SCATTERED MODERATE CONVECTION WAS WITHIN 60 NM EITHER SIDE OF THE AXIS BETWEEN 84W AND 90W. SCATTERED MODERATE TO STRONG CONVECTION WAS FROM 03N TO 08N BETWEEN 93W AND 107W AND ALSO WITHIN 180 NM S OF THE AXIS BETWEEN 118W AND 121W. ...DISCUSSION... AN WEAK UPPER LEVEL LOW LIES NEAR 26N135W. 50-70 KT WEST- SOUTHWEST WINDS ON THE SE SIDE OF THE LOW ARE TRANSPORTING SOME MID TO UPPER LEVEL MOISTURE INTO THE NW PORTION OF THE AREA WHICH IS MARKED BY MULTI-LAYERED CLOUDINESS N OF 17N W OF 126W AS A RESULT. THIS LOW WILL BE OVERTAKEN LATER TODAY BY A NORTHERN STREAM BROAD TROUGH CURRENTLY NW OF THE AREA. A COLD FRONT ASSOCIATED WITH THIS NORTHERN STREAM TROUGH IS SLOWLY APPROACHING THE NW PORTION OF THE FORECAST AREA...BUT SHOULD WEAKEN AS IT MOVES S OF 32N THIS AFTERNOON. THE APPROACH OF THIS FRONT WILL WEAKEN THE 1028 MB SUBTROPICAL HIGH NEAR 30N133W SHIFTING IT SOUTHEASTWARD THROUGH THE DAY. MORE DOMINANT HIGH PRES WILL BUILD IN BEHIND THE COLD FRONT MON MORNING THROUGH TUE MORNING. FRESH TRADE WINDS LIE OVER MUCH OF THE W CENTRAL PORTION OF THE FORECAST AREA ACCORDING TO EARLIER SCATTEROMETER PASSES. AS THE HIGH PRES TO THE N MENTIONED ABOVE WEAKENS AND REORGANIZES TO THE NW...LOOK FOR THE AREA OF FRESH NORTHEAST-EAST TRADES TO SHIFT W AND SLIGHTLY S IN RESPONSE. AN UPPER TROUGH LIES FROM WESTERN WYOMING SW TO ACROSS THE NORTHERN BAJA CALIFORNIA PENINSULA AND INTO THE NE WATERS TO NEAR 20N120W. THIS TROUGH WILL PROCEED THROUGH THE SW CONUS AND ACROSS NORTHERN MEXICO TODAY. AT THE SURFACE...THE PRES GRADIENT HAS TIGHTENED BETWEEN THE SUBTROPICAL RIDGE W OF THE BAJA CALIFORNIA PENINSULA AND A LOW PRES SYSTEM AND ATTENDANT COLD FRONT MOVING THROUGH SOUTHERN TEXAS. FRESH NORTHERLY WINDS HAVE COMMENCED IN THE CENTRAL GULF OF CALIFORNIA THIS MORNING AS THE PRES GRADIENT TIGHTENED. THESE WINDS WILL EXPAND TO ENCOMPASS THE MAJORITY OF THE GULF BY MON MORNING. ALSO THIS TIGHTENING GRADIENT IS NOW SUPPORTING 20 KT NW TO N WINDS WITHIN 180 NM W OF BAJA CALIFORNIA. THESE WINDS WILL GRADUALLY EXPAND W TO 120W THROUGH THE PERIOD. MEANWHILE THE PRES GRADIENT HAS ALREADY BECOME STRONG ENOUGH ON THE EASTERN EDGE OF THE SURFACE RIDGE NEAR CABO CORRIENTES MEXICO TO SUPPORT FRESH TO STRONG NW TO N WINDS WHICH WILL REMAIN IN PLACE THROUGH MON MORNING BEFORE DIMINISHING BY TUE MORNING. A SURFACE TROUGH IS EMBEDDED IN THE ITCZ FROM 10N123W TO 02N127W. THIS TROUGH COINCIDES WITH AN AREA OF INCREASED AVAILABLE MOISTURE ACCORDING TO THE LATEST PRECIPITABLE WATER SATELLITE IMAGERY. THE DIFFLUENT REAR RIGHT QUADRANT OF THE MID TO UPPER LEVEL TROUGH OVER THE NE WATERS HAS TAPPED INTO TROPICAL MOISTURE ALONG THE ITCZ NEAR THIS SURFACE TROUGH. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 120 NM EITHER SIDE OF THE TROUGH. CONVECTIVE BLOW OFF EXTENDS NE OF THE SURFACE TROUGH ALL THE WAY TO THE SOUTHERN TIP OF BAJA CALIFORNIA. AN ANTICYCLONE ALOFT NEAR 16N96W EXTENDS A RIDGE SOUTHWESTWARD TO A COL NEAR 03N122W. BROAD DIFFLUENCE ALOFT BETWEEN THE ANTICYCLONE AND A 30-40 KT EASTERLY JET ALOFT ALONG THE EQUATOR E OF 115W IS ENHANCING VERTICAL LIFT NEAR THE ITCZ. THIS AREA COINCIDES WITH A MAXIMUM IN PRECIPITABLE WATER AS WELL. ASSOCIATED CONVECTION IS AS DESCRIBED IN THE ITCZ SECTION ABOVE. $$ LEWITSKY