000 AXPZ20 KNHC 100231 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC MON JUN 10 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS WSW BETWEEN 09N-11N FROM THE NW COAST OF COLOMBIA ACROSS SE COSTA RICA TO 09N86W...THEN TURNS NW TO 11N107W TO 13N116W...THEN SW TO 07N134W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ. THE ITCZ AXIS CONTINUES JUST S OF DUE W TO BEYOND 07N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 150 NM OF 09.5N101W...AND ALSO WITHIN 75 NM EITHER SIDE OF A LINE FROM 09N107W TO 11N113W TO 07N131W. ISOLATED MODERATE TO STRONG CONVECTION IS NOTED TO THE N OF 05N BETWEEN 93W AND THE COAST OF CENTRAL AMERICA. ...DISCUSSION... AN UPPER CYCLONE IS CENTERED AT 32N123W TRAILING AN UPPER TROUGH SW TO 23N120W. AT THE LOWER LEVELS A SURFACE LOW IS CENTERED AT 32N124W WITH A TROUGH EXTENDING FROM 32N122W TO 24N121W. SURFACE HIGH PRES W OF THIS SURFACE TROUGH IS MAINTAINING NE WINDS AT 20 KT...SEAS TO 9 FT IN N SWELL...ACROSS THE FORECAST WATERS TO THE N OF 29N BETWEEN 126W-135W. A SECOND UPPER CYCLONE HAS BEEN RACING NE OVER THE PAST 24 HOURS AND IS CURRENTLY NEAR 31N141W. THE EASTERNMOST UPPER CYCLONE AT 32N123W IS EXPECTED TO MOVE NE TONIGHT-MON CROSSING OVER CENTRAL CALIFORNIA. THE CYCLONE FURTHER W WILL ALSO MOVE NE REACHING NEAR 31N135W ON MON...AND THEN SLOWLY FILL BEFORE PASSING OVER CALIFORNIA ON WED. THE SURFACE LOW IS EXPECTED TO MOVE S TO NEAR 30.5N125W ON MON WITH A WEAK COLD FRONT...OR MORE LIKELY A NON-BAROCLINIC TROUGH...DEVELOPING TO ITS S AND MOVING INTO THE AREA FROM 32N122W TO 26N127W ON TUE. NE SURFACE WINDS AT 20 KT WILL CONTINUE TO SPREAD SOUTHWARD INTO THE AREA W OF THE TROUGH... ACCOMPANIED BY COMBINED SEAS TO 9 FT THROUGH TUE. THE SURFACE LOW WILL OPEN TO A TROUGH ON TUE AND FILL ON WED...BUT THE NORTHERLY 20 KT WINDS WILL CONTINUE THROUGH THU NIGHT ACROSS THE WATERS NW OF A LINE FROM 32N117W TO 20N140W AS NE TRADES INCREASE TO 20 KT ACROSS THE TROPICS TO THE W OF 125W AND N OF THE MONSOON TROUGH AND ITCZ DURING THE MIDDLE OF THE WEEK. AN UPPER ANTICYCLONE IS CENTERED AT 20123W WITH AN UPPER RIDGE EXTENDING E TO A CREST AT 20N107W. AN UPPER RIDGE ALSO EXTENDS W TO BEYOND 21N127W. THIS RIDGE IS ACCOMPANIED BY DRY UPPER AIR ALOFT...AND CONTINUES TO SUPPRESS CONVECTIVE DEVELOPMENT ACROSS THE AREA TO THE N OF 13N W OF 104W. WEAK UPPER DIFFLUENCE ALONG THE SOUTHERN PERIPHERY OF THIS UPPER RIDGE IS ROUGHLY IN PHASE WITH THE LOWER LEVEL MONSOON TROUGH AXIS...AND IS SUPPORTING THE CONVECTION PREVIOUSLY DESCRIBED BETWEEN 115W-134W. A VIGOROUS UPPER TROUGH OVER THE CENTRAL CONUS IS AMPLIFYING S ACROSS CENTRAL OLD MEXICO WITH EVIDENCE OF AN UPPER CYCLONE DEVELOPING NEAR 26N100W. GUIDANCE SEEMS TO AGREE ON THE DEVELOPMENT...AND CUT OFF THE CYCLONE OVER N-CENTRAL OLD MEXICO ON TUE WITH THE CYCLONE BECOMING ELONGATED TO THE SW OVER THE PACIFIC NEAR 19N112W BY MID WEEK. IN THE MEANTIME THE UPPER TROUGH IS SEPARATING THE UPPER FLOW OVER THE TROPICS TO THE E AND W OF 105W...AND SETTING OFF CLUSTERS OF CONVECTION OVER INTERIOR MEXICO TO THE N OF 20N E OF 109W. AN UPPER ANTICYCLONE IS OVER THE SE GULF OF MEXICO NEAR 24N84W WITH AN UPPER RIDGE EXTENDING SW ACROSS CENTRAL AMERICA BETWEEN 87W-95W TO A CREST OVER THE PACIFIC AT 11N93W. AN UPPER LEVEL CYCLONE IS CUTTING OFF FROM A TUTT OVER THE N-CENTRAL CARIBBEAN IN THE VICINITY OF THE WINDWARD PASSAGE...AND CONTINUES TO HAVE AN UPPER TROUGH EXTENDING SSW ACROSS PANAMA INTO AN UPPER CYCLONE OVER THE DEEP TROPICAL PACIFIC AT 02N81W. THESE UPPER FEATURES COMBINE TO SET OF AN AREA OF UPPER DIFFLUENCE OVER THE TROPICAL PACIFIC E OF 105W AND SUPPORTING THE CONVECTION WITHIN THE EASTERN SEGMENT OF MONSOON TROUGH AS PREVIOUSLY DESCRIBED. $$ NELSON