000 AXPZ20 KNHC 051604 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE MAY 05 2009 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... ITCZ AXIS EXTENDED ALONG 06N77W TO 05N82W TO 07N93W TO 05N115W TO 06N140W. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION WAS NOTED FROM 05N TO 08N W OF 112W. ISOLATED MODERATE CONVECTION WAS NOTED WITHIN 120 NM OF AXIS E OF 98W. ...DISCUSSION... ALOFT...A DEEP LAYERED CYCLONE HAS CUT OFF NEAR 18N135W AND WAS MOVING SLOWLY W WITH TIME. TO IMMEDIATELY TO THE SE...A QUASI STATIONARY UPPER ANTICYCLONE WAS CENTERED AT 09N126W WITH A RIDGE EXTENDING N TO NEAR 20N122W. UPPER DIFFLUENCE OCCURRING ACROSS THE EQUATORIAL CENTRAL PACIFIC IN RESPONSE TO THE PATTERN WAS PRODUCING AN ELONGATED ZONE OF UPPER DIVERGENCE...AND WAS ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 150W AND 110W...WITH MUCH OF THE RESULTANT DEBRIS MOISTURE SPREADING N OVER THE RIDGE AND WRAPPING AROUND THE NORTHERN SEMICIRCLE OF THE CUTOFF CYCLONE. A SECOND MID TO UPPER LEVEL CYCLONE WAS NOTED NEAR 19N118W...AND WAS BEING FORCED GRADUALLY WSW BY ELONGATED RIDGING TO THE NW. DRAPED N OF THESE TWO CYCLONES IS A FLAT SHORTWAVE RIDGE WITH A CENTER ESTIMATED NEAR 28N123W...WITH THE RIDGE EXTENDING NE TO CENTRAL ARIZONA AND OFFSHORE OF NRN BAJA CALIFORNIA...WHERE SOME DENSE UPPER MOISTURE WAS OBSERVED. OTHERWISE THE UPPER LEVELS ARE DRY N OF 20N...AND OVER THE SW SEMICIRCLE OF THE WESTERNMOST CYCLONE. A BROAD UPPER TROUGH DOMINATES THE E CENTRAL CONUS AND EXTENDS SW ACROSS OLD MEXICO AND THEN S OVER THE E PACIFIC ALONG 109W AND THEN S TO NEAR THE EQUATOR. DRY SINKING AIR WAS NOTED FROM 07N TO 20N BETWEEN 106W AND 115W AND WAS SUPPRESSING CONVECTION. A STATIONARY UPPER RIDGE EXTENDS NW OFF COLOMBIA ALONG THE PACIFIC COAST OF CENTRAL AMERICA TO A CREST NEAR 18N100W. ASSOCIATED UPPER DIFFLUENCE HAS BEEN ENHANCING CONVECTION ALONG THE PACIFIC ITCZ TO THE E OF 100W...AND MAY ALSO ENHANCED QUITE OF BIT OF CONVECTION OVER CENTRAL AMERICA BETWEEN 85W AND 93W TODAY DURING THE DIURNAL HEATING CYCLE. AT THE SURFACE...A 1022 MB HIGH WAS QUASI STATIONARY NEAR 27N134W WITH A RIDGE EXTENDING SW TO BEYOND 25N140W...AND SECOND RIDGE EXTENDING SE TO NEAR 14N112W. THE RIDGE IS BLOCKING THE SOUTHEAST PROGRESSION OF A SERIES OF COLD FRONTS TO N OF 30N. HOWEVER NW LARGE NW SWELLS GENERATED BY THESE FRONTAL SYSTEMS TO THE NW WILL PROPAGATE SE INTO THE AREA DURING THE NEXT 48 HOURS...AND RAISE SEA HEIGHTS TO 10 FT AND GREATER ACROSS EXTREME N PORTIONS TONIGHT THROUGH THU. TO THE E OF THIS SURFACE RIDGE...NORTHERLY WINDS AROUND 20 KT PERSIST ALONG THE PACIFIC COAST OF THE BAJA PENINSULA AND ARE EXPECTED TO CHANGE LITTLE TODAY...BUT INCREASE TO 20 TO 25 KT WED WITH SEAS BUILDING TO 13 FT IN NW SWELL NEAR 29N119W WED NIGHT INTO THU. EASTERLY TRADES S OF THE RIDGE AND N OF THE ITCZ ARE MOSTLY IN THE 15 TO 20 KT RANGE...WITH MODEST ZONES OF 20 KT FLOW...AND NOT EXPECTED TO CHANGE MUCH FOR THE NEXT COUPLE OF DAYS. VERY LONG PERIOD SSW SRN HEMI SWELL WILL BEGIN TO MOVE INTO THE AREA LATE TONIGHT AND MIX WITH PREVAILING WAVE ENERGY ACROSS THE REGION OVER THE NEXT FEW DAYS. MODERATE TO OCCASIONALLY LARGE SURF WILL AFFECT THE COASTLINES OF NW S AMERICA AND CENTRAL AMERICA...AND EVENTUALLY REACH CALIFORNIA LATE TONIGHT THROUGH FRIDAY. $$ STRIPLING