000 AXPZ20 KNHC 152125 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT JUN 15 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... TROPICAL WAVE OVER THE EASTERN PORTION OF THE AREA IS ANALYZED ALONG 95W FROM 09N TO 15N MOVING W ABOUT 10 KT. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS NOTED NEAR THE SOUTHERN END OF THE WAVE AXIS...WHERE THE WAVE MEETS THE ITCZ AXIS. THE FEATURE COINCIDES WITH A MAXIMUM IN DEEP LAYER MOISTURE PRESENT IN TOTAL PRECIPITABLE WATER. THE WAVE IS FORECAST TO WEAKEN AS IT REACHES NEAR 100W TONIGHT...THEN BECOME LESS DISCERNIBLE AT THE SURFACE BY SUN NIGHT. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 10N96W TO 10N110W TO 08N116W. ITCZ AXIS CONTINUES FROM 08N116W TO 10N125W TO 08140W. THE MONSOON TROUGH IS PRETTY ACTIVE THIS AFTERNOON WITH NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION NOTED FROM 07N TO 13N BETWEEN 96W AND 111W. ...DISCUSSION... ALOFT...W TO SW FLOW IS EVIDENT ACROSS THE FORECAST AREA MAINLY N OF 20N W OF 110W IN ASSOCIATION WITH A BROAD UPPER LEVEL TROUGH. MODERATE TO STRONG SUBSIDENCE AND IMPLIED DRY AIR MASS IS NOTED UNDER THE INFLUENCE OF THESE WINDS. OVER THE FAR SE PORTION OF THE AREA...AN ANTICYCLONE DRIFTING W IS LOCATED OVER WEST/CENTRAL MEXICO NEAR 19N102W WITH AN ASSOCIATED RIDGE EXTENDING SE ALONG THE COAST OF MEXICO TO NEAR 12N92W. UPPER DIFFLUENCE ALONG THE SOUTHERN PERIPHERY OF THE RIDGE IS HELPING TO INDUCE THE AREA OF NUMEROUS SHOWERS AND TSTMS PREVIOUSLY MENTIONED BETWEEN 96W AND 111W. ANOTHER RIDGE EXTENDS FROM THE SAME ANTICYCLONE TO THE N TOWARDS TEXAS. JUST TO THE E OF THE AREA...AN UPPER LEVEL TROUGH ACROSS THE NW CARIBBEAN STRETCHES FROM CENTRAL CUBA SW TO A BASE NEAR THE PACIFIC COASTS OF EL SALVADOR AND HONDURAS. AN E TO W RIDGE OVER NORTHERN SOUTH AMERICA DOMINATES THE REMAINDER OF THE FORECAST AREA. A PERSISTENT SURFACE TROUGH IS ANALYZED N OF THE ITCZ ALONG 135W FROM 09N TO 16N. THE TROUGH COINCIDES WITH A BULGE OF DEEP LAYER MOISTURE AS OBSERVED IN THE TOTAL PRECIPITABLE WATER PRODUCT. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS AHEAD OF THE TROUGH AXIS COVERING THE AREA FROM 11N TO 13N BETWEEN 135W AND 139W. THE TROUGH IS FORECAST BY THE COMPUTER MODELS TO MOVE W OF THE FORECAST AREA ON SUN. NE WINDS OF 20 KT AND SEAS OF 8 TO 9 FT WILL ACCOMPANY THIS TROUGH. A 1025 MB HIGH PRES LOCATED NEAR 32N141W EXTENDS A RIDGE ACROSS THE N WATERS TO NEAR 20N110W. PRES GRADIENT BETWEEN THIS RIDGE AND GENERALLY LOWER PRES OVER THE U.S. W COAST IS SUPPORTING FRESH TO STRONG WINDS ALONG THE NORTH-CENTRAL COAST OF CALIFORNIA. NW TO N SWELLS OF 8 TO 9 FT RELATED TO THESE WINDS ARE STILL PROPAGATED S AND SE ACROSS THE NORTH WATERS MAINLY N OF 29N BETWEEN 123W AND 128W. SEAS ARE EXPECTED TO SUBSIDE TO LESS THAN 8 FT TONIGHT AS THE PRES GRADIENT JUST NE OF THE AREA RELAXES. AS THE HIGH PRES MOVES EWD TO A POSITION NEAR 30N135W BY 24 HOURS...EXPECT INCREASING TRADE WINDS AND BUILDING SEAS. MARINE GUIDANCE SUGGESTS WINDS OF 20-25 KT AND SEAS OF 8-10 FT PARTICULARLY ON MON. LONG PERIOD CROSS EQUATORIAL SW SWELLS...WITH LEADING EDGE PERIOD OF 16-17 SECONDS DOMINATE MOST OF THE WATERS E OF 118W AND THESE SWELLS ARE MERGING WITH THE NW SWELLS AFFECTING THE NE WATERS. ADDITIONAL PULSES OF SW SWELLS WILL INVADE THE SOUTH- CENTRAL WATERS TONIGHT AND SUN...REACHING THE COASTLINE OF CENTRAL AMERICA AND MEXICO BY MON. $$ GR