000 AXPZ20 KNHC 010258 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC WED MAY 01 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 0300 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH EXTENDS NW FROM THE COAST OF COLOMBIA AT 06N77W ACROSS THE PACIFIC COASTS OF PANAMA AND COSTA RICA TO 10N87W...THEN DIPS SW TO 05N114W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ. THE ITCZ AXIS CONTINUES W-NW TO 08N132W TO AN EMBEDDED 1010 MB LOW PRES ANALYZED AT 08.5N137W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED ALONG THE THE MONSOON TROUGH AXIS ROUGHLY WITHIN 90 NM EITHER SIDE OF A LINE FROM 09N89W TO 07N96W. SIMILAR CONVECTION IS NOTED ALONG THE ITCZ AXIS WITHIN 90 NM EITHER SIDE OF A LINE FROM 06N126W TO 08N131W. SCATTERED MODERATE CONVECTION IS NOTED ALONG THE MONSOON TROUGH WITHIN 75 NM OF 06N119W. THE LOW PRESSURE SYSTEM AT 08.5N137W IS EXPECTED TO MOVE W AND DISSIPATE OVER THE NEXT 24 HOURS. A LOW LEVEL TROUGH HAS DEVELOPED S OF THE MONSOON TROUGH FROM 03N82W TO 05N86W WITH A SMALL CONVECTIVE BURST NOTED AT 03.5N84.5W. LOCALLY OVERCAST MULTI-LAYERED CLOUDS ARE ENHANCED ALONG THE W PERIPHERY OF AN UPPER RIDGE IN THE AREA JUST N OF THE ITCZ FROM 11N TO 17N BETWEEN 120W AND 125W WITH CLUSTERS OF MODERATE CONVECTION FLARING INTERMITTENTLY. THE RESULTANT DEBRIS MOISTURE CONCENTRATES INTO A 240 NM WIDE MOISTURE PLUME THAT STREAMS E ACROSS MEXICO ALONG 19N THEN TURNS NE ACROSS THE SOUTHERN GULF OF MEXICO AND ACROSS S FLORIDA. ...DISCUSSION... GULF OF CALIFORNIA...S TO SW WINDS ARE AT 5 TO 10 KT ACROSS THE ENTIRE THE GULF OF CALIFORNIA WITH SEAS 1 TO 2 FT EXCEPT 2 TO 3 FT OVER THE SOUTHERN GULF WATERS PRIMARILY DUE TO LONG PERIOD SOUTHERLY SWELL. THE SOUTHERLY FLOW WILL INCREASE TO 10 TO 15 KT LATE TONIGHT INTO EARLY WED... THEN DIMINISH TO 5 TO 10 KT BRIEFLY BY MIDDAY WED. THE LIGHT LOW LEVEL FLOW WILL BECOME NW ON WED NIGHT. THE NW WINDS WILL INCREASE TO 10 TO 15 KT ON THU MORNING AND THEN QUICKLY INCREASE TO 15 TO 20 KT ACROSS THE ENTIRE GULF ON THU AFTERNOON...AND FURTHER INCREASE TO 20 TO 25 KT ON THU EVENING AS SEAS BUILD TO 5 TO 8 FT ACROSS THE WATERS N OF 26N. THE NW WINDS WILL DIMINISH LATE THU NIGHT INTO FRI WITH LIGHT AND VARIABLE WINDS AND SEAS 2 FT OR LESS EXPECTED ON SAT. GULF OF TEHUANTEPEC...S TO SW WINDS AT 5 TO 15 KT ARE EXPECTED ACROSS THE GULF OF TEHUANTEPEC THROUGH THU EVENING. NORTHERLY WINDS WILL SURGE THROUGH THE CHEVILA PASS LATE THU NIGHT...INITIALLY AT 10 TO 15 KT...BUT QUICKLY INCREASE 20 TO 25 KT BY FRI AFTERNOON WITH SEAS BUILDING TO 10 FT. THE N FLOW WILL INCREASE TO 20 TO 30 KT FRI NIGHT WITH A SMALL AREA OF MINIMAL GALE FORCE WINDS EXPECTED LATE FRI NIGHT JUST AFTER THROUGH SUNRISE ON SAT...WITH SEAS BUILDING TO 13 FT NEAR 14.5N95W AT SUNRISE SAT. THE WINDS WILL DIMINISH SAT MORNING WITH SEAS OF 8 TO 10 FT REACHING AS FAR S AS 10.5N96.5W. GULF OF PAPAGAYO...LIGHT AND VARIABLE WINDS AND LONG PERIOD SW SWELL...WITH SEAS 3 TO 5 FT...ARE EXPECTED THROUGH SAT EVENING...THEN E-NE FLOW AT 10 TO 15 KT FORECAST LATE SAT NIGHT INTO SUN MORNING. GULF OF PANAMA...LIGHT AND VARIABLE WINDS AT 5 TO 10 KT ARE EXPECTED THROUGH SUN. SURFACE HIGH PRESSURE IS ANALYZED NW OF THE AREA WITH A RIDGE AXIS EXTENDING SE INTO THE DISCUSSION AREA FROM 32N134W TO 16N115W. THE GRADIENT IS SUPPORTING N WINDS AT 15 TO 20 KT ACROSS THE PACIFIC WATERS N OF 28N BETWEEN 123W AND 133W WITH SEAS 7 TO 10 FT IN MIXING N AND S SWELL. THE AFFECTED AREA WILL EXPAND S TO ALONG 27N BETWEEN 118W AND 135W ON WED... THEN BEGIN TO SHRINK WITH WINDS LESS THAN 20 KT AND SEAS LESS THAN 8 FT ON THU. A SMALL AREA OF ENHANCED NE TRADE WINDS AT 15 TO 20 KT ARE NOTED SW OF THE RIDGE IN THE AREA FROM 10N TO 14N BETWEEN 129W AND 136W...WITH SEAS 6 TO 8 FT IN MIXED NE AND S SWELL. THESE NE TRADES WILL DIMINISH BELOW 20 KT ON THU AS SEAS SUBSIDE TO LESS THAN 8 FT. THE RIDGE WILL SHIFT S LATE IN THE WEEK ALLOWING A WEAK COLD FRONT TO SWEEP E ACROSS THE PACIFIC WATERS N OF 27N BETWEEN 120W AND 130W...ACCOMPANIED BY ONLY A 15 TO 20 KT SW TO W TO NW WIND SHIFT. $$ NELSON