000 AXPZ20 KNHC 121550 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE JUL 12 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...ITCZ/MONSOON TROUGH... DISCONTINUOUS MONSOON TROUGH AXIS FROM 11N86W TO 19N105W RESUMES FROM 18N118W TO 13N120W TO 07N135W THEN ITCZ TO 06N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM OF MONSOON TROUGH BETWEEN 90W AND 95W...AND WITHIN 120 NM S OF MONSOON TROUGH BETWEEN 102W AND 105W. ...DISCUSSION... THE REMNANT LOW OF CALVIN NEAR 19N118W CONTINUES TO DISSIPATE AS IT MOVES W OVER COOLER SEA SURFACE TEMPERATURES. AN ASCAT PASS AT 0544 UTC SHOWED 15-20 KT WINDS ON SWATH EDGE ABOUT 40 NM NW OF THE CENTER. THE REMNANT OF CALVIN HAS WEAKENED THE PRES GRADIENT W OF 110W...KEEPING TRADE WIND FLOW FAIRLY LIGHT. FURTHER NORTH...SHIPS ARE REPORTING SEAS OF 7 TO 8 FT N OF 27N IN N SWELL. ALTIMETER PASSES OVER THE PAST 12 HOURS SHOW SEAS UP TO 9 FT E OF 110W. THIS IS LIKELY DUE TO LINGERING CROSS-EQUATORIAL SW SWELL. SCATTEROMETER DATA SHOW SOUTHERLY WINDS OF 15 TO 20 KT ROUGHLY FROM 03N T0 08N E OF 100W. RELATED LOW LEVEL CONVERGENCE INTO THE MONSOON TROUGH IS INTERACTING WITH LEFTOVER OVERNIGHT LAND BREEZES AND AIDING IN SCATTERED MODERATE CONVECTION ALONG THE COAST FROM PANAMA TO SOUTHERN MEXICO. THESE WINDS WILL INCREASE TO SET UP AN UNUSUALLY STRONG MONSOON TROUGH OVER SOUTHERN MEXICO AND CENTRAL AMERICA OVER THE NEXT SEVERAL DAYS. SW MONSOONAL FLOW WILL STRENGTHEN OVER THE E PART OF THE AREA. WHILE STRONGEST WINDS AND HIGHEST SEAS ARE EXPECTED TO BE S OF EL SALVADOR...THE EFFECTS ASSOCIATED WITH THIS INTENSE MONSOON TROUGH WILL STRETCH ACROSS ALL OF CENTRAL AMERICA. THE MONSOONAL FLOW WILL ADVECT ABUNDANT TROPICAL MOISTURE...WITH PW VALUES IN EXCESS OF 2.0 INCHES...INTO CENTRAL AMERICA AND SOUTHERN MEXICO. STRONG W-SW WINDS WILL PERSIST THROUGH AT LEAST THIS WEEKEND...AND PERHAPS INTO THE BEGINNING OF NEXT WEEK. THIS WILL SET UP A POTENTIALLY VERY DANGEROUS SITUATION FOR CENTRAL AMERICA AND SOUTHERN MEXICO WITH PROLONGED HEAVY RAINFALL WHICH WILL LEAD TO FLASH FLOODING AND MUDSLIDES...ESPECIALLY IN AREAS OF HILLY OR MOUNTAINOUS TERRAIN. $$ CHRISTENSEN 000 AXPZ20 KNHC 121550 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC TUE JUL 12 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...ITCZ/MONSOON TROUGH... DISCONTINUOUS MONSOON TROUGH AXIS FROM 11N86W TO 19N105W RESUMES FROM 18N118W TO 13N120W TO 07N135W THEN ITCZ TO 06N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM OF MONSOON TROUGH BETWEEN 90W AND 95W...AND WITHIN 120 NM S OF MONSOON TROUGH BETWEEN 102W AND 105W. ...DISCUSSION... THE REMNANT LOW OF CALVIN NEAR 19N118W CONTINUES TO DISSIPATE AS IT MOVES W OVER COOLER SEA SURFACE TEMPERATURES. AN ASCAT PASS AT 0544 UTC SHOWED 15-20 KT WINDS ON SWATH EDGE ABOUT 40 NM NW OF THE CENTER. THE REMNANT OF CALVIN HAS WEAKENED THE PRES GRADIENT W OF 110W...KEEPING TRADE WIND FLOW FAIRLY LIGHT. FURTHER NORTH...SHIPS ARE REPORTING SEAS OF 7 TO 8 FT N OF 27N IN N SWELL. ALTIMETER PASSES OVER THE PAST 12 HOURS SHOW SEAS UP TO 9 FT E OF 110W. THIS IS LIKELY DUE TO LINGERING CROSS-EQUATORIAL SW SWELL. SCATTEROMETER DATA SHOW SOUTHERLY WINDS OF 15 TO 20 KT ROUGHLY FROM 03N T0 08N E OF 100W. RELATED LOW LEVEL CONVERGENCE INTO THE MONSOON TROUGH IS INTERACTING WITH LEFTOVER OVERNIGHT LAND BREEZES AND AIDING IN SCATTERED MODERATE CONVECTION ALONG THE COAST FROM PANAMA TO SOUTHERN MEXICO. THESE WINDS WILL INCREASE TO SET UP AN UNUSUALLY STRONG MONSOON TROUGH OVER SOUTHERN MEXICO AND CENTRAL AMERICA OVER THE NEXT SEVERAL DAYS. SW MONSOONAL FLOW WILL STRENGTHEN OVER THE E PART OF THE AREA. WHILE STRONGEST WINDS AND HIGHEST SEAS ARE EXPECTED TO BE S OF EL SALVADOR...THE EFFECTS ASSOCIATED WITH THIS INTENSE MONSOON TROUGH WILL STRETCH ACROSS ALL OF CENTRAL AMERICA. THE MONSOONAL FLOW WILL ADVECT ABUNDANT TROPICAL MOISTURE...WITH PW VALUES IN EXCESS OF 2.0 INCHES...INTO CENTRAL AMERICA AND SOUTHERN MEXICO. STRONG W-SW WINDS WILL PERSIST THROUGH AT LEAST THIS WEEKEND...AND PERHAPS INTO THE BEGINNING OF NEXT WEEK. THIS WILL SET UP A POTENTIALLY VERY DANGEROUS SITUATION FOR CENTRAL AMERICA AND SOUTHERN MEXICO WITH PROLONGED HEAVY RAINFALL WHICH WILL LEAD TO FLASH FLOODING AND MUDSLIDES...ESPECIALLY IN AREAS OF HILLY OR MOUNTAINOUS TERRAIN. $$ CHRISTENSEN