000 AXPZ20 KNHC 122133 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC WED JUN 12 2013 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2100 UTC. ...TROPICAL WAVES... A TROPICAL WAVE EXTENDS ALONG 81W N OF 07N ACROSS WESTERN PANAMA INTO THE CARIBBEAN SEA TO 14N. THE WAVE IS INTERACTING WITH THE MONSOON TROUGH...AS NOTED BY A LARGE SWATH OF SW SURFACE FLOW OVER THE EASTERN PACIFIC. IN ADDITION...AN UPPER LEVEL TROUGH EXTENDING ACROSS THE SW CARIBBEAN IS INTERACTING WITH THE TROPICAL WAVE AND MONSOON TROUGH TO ENHANCE THE ASSOCIATED CONVECTION. IR SATELLITE IMAGERY SHOWS A CLUSTER OF MODERATE TO STRONG CONVECTION JUST EAST OF THE WAVE AXIS OVER THE SW CARIBBEAN WHILE SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS NOTED ON THE EPAC SIDE MAINLY N OF 06N BETWEEN 80W AND 84W. WAVE GROWTH IS SUPPORTED BY FRESH TO STRONG E FLOW IN THE MID LEVELS OF THE ATMOSPHERE. THESE FAVORABLE CONDITIONS WILL PERSIST THROUGH 48 HOURS AS THE WAVE MOVES INTO THE EASTERN PACIFIC TOWARD 90W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH ALONG 09N85W TO LOW PRES NEAR 12N113W 1009 MB TO 09N125W THEN ITCZ AXIS TO BEYOND 07N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS N OF 06N BETWEEN 80W AND 84W...AND WITHIN 45 NM N OF ITCZ AXIS W OF 138W. ...DISCUSSION... A 1009 MB LOW PRES REMAINS EMBEDDED WITHIN THE MONSOON TROUGH NEAR 12N113W. A TROUGH EXTENDS FROM THE LOW TO NEAR 17N108W. AN EARLIER ASCAT PASS REVELEAD THE WIND SHIFT ASSOCIATED WITH THE TROUGH. AN AREA OF MODERATE TO ISOLATED STRONG CONVECTION IS SEEN NEAR THE NORTHERN END OF THE TROUGH AXIS COVERING FROM 16N TO 18N BETWEEN 108W AND 112W. A SWIRL OF MAINLY LOW CLOUDS IS RELATED TO THE LOW CENTER AS OBSERVED ON VISIBLE SATELLITE IMAGERY. THIS SYSTEM WILL MIGRATE W THROUGH 48 HOURS INTO LESS FAVORABLE AREAS BOTH IN TERMS OF AVAILABLE MOISTURE AND UPPER SUPPORT. STRONG HIGH PRES SITUATED NW OF AREA NEAR 39N142W EXTENDS A RIDGE SE OVER THE N WATERS TO NEAR 23N115W. THIS SYSTEM IS PRODUCING NE WINDS OF 20 KT OVER THE NW CORNER OF THE FORECAST AREA PER THE 1806 UTC ASCAT PASS. ANOTHER AREA OF 20KT WINDS IS NOTED ALONG THE SOUTHERN PERIPHERY OF THE RIDGE N OF THE ITCZ AND W OF 134W. THIS FEATURE WILL MOVE ESE DURING THE NEXT 24 HOURS AND COULD BRIEFLY INCREASE WINDS TO 25 KT ACROSS THE NW WATERS...PARTICULARLY N OF 26N W OF 130W...TONIGHT INTO THU MORNING. ALOFT...AN ELONGATED UPPER CYCLONE IS OVER SOUTHERN BAJA CALIFORNIA WITH A TROUGH EXTENDING S TO ABOUT 17N116W. UPPER DIVERGENCE ALOFT BETWEEN THIS FEATURE AND AN UPPER ANTICYCLONE CENTERED OVER SOUTH-CENTRAL MEXICO IS SUPPORTING THE AFOREMENTIONED WEAK SURFACE LOW PRES AREA. A LONGWAVE UPPER TROUGH EXTENDS FROM OFF THE OREGON COAST TO NEAR 24N131W. AN ANTICYCLONE LOCATED NEAR 19N142W EXTENDS A RIDGE OVER THE WEST CENTRAL WATERS TO NEAR 18N130W. EASTERLY WINDS ALOFT DOMINATE THE REMAINDER OF THE DISCUSSION AREA...MAINLY E OF 110W. THESE WINDS ARE TRANSPORTING ABUNDANT MID TO UPPER LEVEL MOISTURE. N TO NE SWELL OF 8 TO 10 FT ASSOCIATED WITH WINDS TO GALE FORCE OFF THE COAST OF CENTRAL CALIFORNIA ARE PROPAGATING OVER THE WATERS NW OF LINE FROM 30N130W TO 20N140W...AS NOTED IN THE MOST RECENT ALTIMETER PASS. FINALLY...LONG PERIOD CROSS EQUATORIAL SW SWELLS...WITH WAVE PERIOD OF 15-16 SECONDS WILL CONTINUE TO IMPACT THE FORECAST AREA E OF 115W. A NEW SW SWELL TRAIN WITH LEADING EDGE PERIOD OF 18-19 SECONDS IS ALREADY AFFECTING THE SOUTH CENTRAL WATERS AND IS FORECAST TO REACH THE COASTLINE THU NIGHT. $$ GR