000 AXPZ20 KNHC 181541 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC MON JUN 18 2012 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 1430 UTC. ...SPECIAL FEATURES... A BROAD LOW PRESSURE SYSTEM LOCATED NEAR 17.5N108W IS PRODUCING A LARGE AREA OF SHOWERS WITH EMBEDDED THUNDERSTORMS. NUMEROUS MODERATE TO ISOLATED STRONG CONVECTION IS NOTED WITHIN 120 NM S SEMICIRCLE OF LOW CENTER. SCATTERED MODERATE CONVECTION IS SEEN IN A SW WIND FLOW FROM 12N TO 16N BETWEEN 103W AND 110W. A BAND OF MODERATE TO ISOLATED STRONG CONVECTION IS ALSO OBSERVED ALONG THE COASTLINE OF MEXICO FROM 17N TO 20N E OF 107W. SOME SLOW DEVELOPMENT OF THIS LARGE DISTURBANCE IS POSSIBLE DURING THE NEXT COUPLE OF DAYS AS IT MOVES SLOWLY EASTWARD. THIS SYSTEM HAS A MEDIUM CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. REGARDLESS OF DEVELOPMENT...HEAVY RAINFALL AND THE THREAT FOR FLASH FLOODS AND MUDSLIDES WILL CONTINUE OVER PORTIONS OF SOUTHWESTERN AND SOUTH-CENTRAL MEXICO FOR THE NEXT COUPLE OF DAYS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH FROM 04N77W TO 07N95W THEN FROM 1005MB LOW PRES NEAR 17.5N108W TO 15N115W TO 06N130W TO 03N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION CAN BE FOUND WITHIN 180 SE OF TROUGH FROM 116W TO 124W. ...DISCUSSION... ALOFT...AN UPPER LEVEL LOW IS SPINNING NEAR 25N132W. A TROUGH EXTENDS FROM THE LOW TO BEYOND 17N140W. SATELLITE IMAGERY INDICATES A NARROW BAND OF HIGH CLOUDS AROUND THE LOW CENTER. AN 95-105 KT NLY JETSTREAM IS W OF LOW CENTER EXTENDING FROM 31N131W TO 25N135W WITH 70-90 KT SLY JET E OF THE LOW FROM 22N130W TO 31N124W. AN ANTICYCLONIC CIRCULATION IS CENTERED OVER SOUTHERN BAJA CALIFORNIA. UPPER DIFFLUENCE ASSOCIATED WITH THIS FEATURE IS HELPING TO INDUCE CONVECTION NEAR THE LOW PRES LOCATED NEAR 17.5N108W AND S OF THE MONSOON TROUGH. UPPER LEVEL NLY WINDS DOMINATE THE WATERS E OF 105W. AT THE SURFACE...A TROUGH EXTENDS FROM 30N128W TO 18N134W. PRES GRADIENT BETWEEN THIS TROUGH AND STRONG HIGH PRES CENTERED WELL NW OF THE AREA IS PRODUCING NLY WINDS OF 20 TO 25 KT W OF THE TROUGH AXIS WITH SEAS OF 8-11 FT. SCATTEROMETER DATA CONFIRMED THE PRESENCE OF THESE WIND SPEEDS. BASED ON THE COMPUTER MODEL...THE TROUGH WILL DRIFT WWD AND THE HIGH PRES WILL SLIGHTLY WEAKEN RESULTING IN A GRADUAL DECREASE IN WINDS AND SEAS ACROSS THE NW WATERS OVER THE NEXT COUPLE OF DAYS. SW WINDS OF 20-25 KT ARE NOTED IN A LARGE AREA SE OF LOW PRES CENTER NEAR 17.5N108W COVERING ROUGHLY FROM 12N TO 17N BETWEEN 101W AND 113W. THE MOST RECENT SCATTEROMETER PASS PROVIDED OBSERVATIONS OF THESE WINDS. THE SW FLOW EXTENDS FARTHER E ALONG THE PACIFIC COAST OF MEXICO AND NORTHERN CENTRAL AMERICA. THIS FLOW IS BRINGING ABUNDANT TROPICAL MOISTURE TO THOSE AREAS WITH THE POTENTIAL OF LOCALLY HEAVY RAIN AND THE THREAT FOR FLASH FLOODS AND MUDSLIDES...PARTICULARLY OVER THE MOUNTAINOUS TERRAIN. CLUSTERS OF MODERATE TO ISOLATED STRONG CONVECTION ARE EMBEDDED WITHIN THIS SW FLOW N OF 12N BETWEEN 87W AND 94W. A WEAK CYCLONIC TURNING IS NOTED IN THE CLOUD FIELD NEAR 14N93W. $$ GR