000 AXPZ20 KNHC 042201 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SAT JUN 04 2011 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 2145 UTC. ...SPECIAL FEATURE... .A TROPICAL LOW PRESSURE CENTER HAS DEVELOPED WITHIN A PERSISTENT AREA OF LOW PRESSURE AT 11N98W...AND IS ESTIMATED AT 1008 MB. CURRENTLY ASCAT DATA INDICATES NE TO E WINDS AT 15 TO 20 KT WITHIN 120 NM OVER THE N SEMICIRCLE...WITH SEAS ESTIMATED AT 6 TO 8 FT. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 90 NM EITHER SIDE OF A LINE FROM 14N93W TO 10N100W. THE LOW IS EXPECTED TO MOVE SLOWLY W TO NEAR 11N100W SUN AFTERNOON WITH MINIMUM PRESSURE DROPPING TO ABOUT 1006 MB. SURFACE WINDS ARE EXPECTED TO INCREASE TO 20 TO 25 KT WITHIN 180 NM OVER THE NW AND 240 NM OVER THE SE SEMICIRCLES...WITH POSSIBLE TROPICAL CYCLONE FORMATION. ...ITCZ/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS FROM 12N87W TO THE SURFACE LOW AT 11N98W..WITH THE TROUGH CONTINUING W THROUGH ANOTHER CYCLONIC SWIRL ANALYZED AS A LOW PRESSURE CENTER AT 09N115W 1012 MB...WITH THE MONSOON TROUGH CONTINUING SW TO NEAR 05N140W WHERE LOW LEVEL WINDS INDICATE THE ITCZ BEGINS. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED IN SOUTHWESTERLY FLOW TO THE S OF THE MONSOON TROUGH AXIS...FROM 04N TO 09N BETWEEN 79W AND 87W. SIMILAR CONVECTION SURROUNDS THE EMBEDDED SURFACE LOW AT 09N115W...ROUGHLY FROM 08N TO 12N BETWEEN 111W AND 118W. LOCALLY OVERCAST LOW AND MID LEVEL CLOUDS...WITH EMBEDDED SHOWERS...ARE NOTED ELSEWHERE WITHIN 150 NM OF A LINE FROM 04N103W TO 10N116W TO BEYOND 04N140W. ...DISCUSSION... A DEEP LAYERED CYCLONE IS OVER THE PACIFIC NEAR 36N127W WITH A SERIES OF SHORT WAVE TROUGHS ROTATING SE AROUND THE CYCLONE INTO THE DISCUSSION AREA. CURRENTLY A NEGATIVE TILT UPPER TROUGH EXTENDS FROM 32N128W TO 16N125W WITH AND A SECOND UPPER SHORTWAVE NOTED TO THE N OF 20N ALONG 134W. AN UPPER ANTICYCLONE IS CENTERED NEAR 20N110W WITH A RIDGE EXTENDING NE TO A SHARP CREST OVER N CENTRAL OLD MEXICO AT 30N101W. UPPER MOISTURE IS ROTATING THROUGH THE UPPER TROUGHS...AND IS SPREADING NE ACROSS CALIFORNIA AND WESTERN ARIZONA. AN UPPER ANTICYCLONE IS W OF THE AREA WITH AN UPPER RIDGE EXTENDING E OVER THE DEEP TROPICS ALONG 06N140W TO 09N132W. ASSOCIATED UPPER DIFFLUENCE IS ONLY ENHANCING WEAK SHOWERS ALONG THE MONSOON TROUGH AXIS OF 130W. AN UPPER TROUGH CONTINUES W ACROSS THE GULF OF MEXICO THROUGH AN UPPER CYCLONE AT 25N92W THEN TURNING SW ACROSS CENTRAL OLD MEXICO ALONG 18N99W AND INTO AN UPPER CYCLONE OVER THE E PACIFIC AT 14N105W...WITH THE UPPER TROUGH CONTINUING S ACROSS THE EQUATOR AT 98W. DEBRIS MOISTURE FROM CONVECTION NEAR 10N115W REMAINS IN THE AREA BOUNDED BY 07N TO 14N BETWEEN 110W AND 120W. OTHERWISE THE UPPER LEVELS APPEAR VERY DRY W OF 102W. AN UPPER ANTICYCLONE IS CENTERED OVER THE S CENTRAL CARIBBEAN WITH A RIDGE EXTENDING W TO A CREST NEAR 17N95W. DEBRIS MOISTURE FROM THE CONVECTION ASSOCIATED WITH THE TROPICAL SURFACE LOW AT 11N98W IS SPREADING NE ACROSS THE MEXICAN COAST BETWEEN 92W AND 98W. UPPER DIFFLUENCE S OF THE RIDGE IS SUPPORTING THE PREVIOUSLY CONVECTION OVER THE DEEP TROPICS TO THE S OF THE MONSOON TROUGH. SOME OF THE RESULTANT DEBRIS MOISTURE IS ADVECTED S ACROSS THE EQUATOR BETWEEN 80W AND 90W...AND SOME MOISTURE ALSO SPREADS NE AROUND THE RIDGE AXIS ACROSS CENTRAL AMERICA AND ACROSS THE W CARIBBEAN. ELSEWHERE AT THE LOW LEVELS A COLD FRONT EXTENDS FROM 32N122W TO 27N140W WITH A W TO E RIDGE ALONG 20N TO THE W OF 112W. NORTHERLY WINDS AT 15 TO 20 KT ACCOMPANY THE FRONT WITH SEAS TO 9 FT. NE TRADES ARE ALSO ENHANCED S OF THE RIDGE WITHIN THE AREA FROM 08N TO 18N BETWEEN 134W AND 140W. THE GRADIENT IS EXPECTED RELAX TONIGHT INTO EARLY SUN WITH ONLY A SMALL AREA OF NE TRADES AT 15 TO 20 KT PERSISTING NEAR 13N137W BY LATE SUN. A NEW BATCH OF CROSS EQUATORIAL SWELL...RESULTING IN COMBINED SEAS TO 8 FT...WILL MOVE INTO THE WATERS S OF 10N BETWEEN 125W AND 92W ON SUN. GAP WINDS...NORTHERLY WINDS AT 15 TO 20 KT ARE EXPECTED TO SURGE THROUGH THE CHIVELA PASS AND INTO AND DOWNSTREAM OF THE GULF OF TEHUANTEPEC BEGINNING LATE TONIGHT...AND INCREASE TO 20 TO 25 KT SUN AFTERNOON. THE DURATION OF THIS EVENT IS SOMEWHAT DEPENDENT OF THE STRENGTH AND TRACK OF THE TROPICAL LOW PRESSURE CURRENTLY NEAR 11N98W. $$ NELSON