000 AXPZ20 KNHC 301551 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC SAT JUN 30 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 1545 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A MONSOON TROUGH AXIS EXTENDS ACROSS THE SW CARIBBEAN ALONG 09W FROM COLOMBIA TO COSTA RICA...THEN CONTINUES SW FROM THE COAST AT 10N85W TO 08N94W. A 1010 MB SURFACE LOW IS STILL EVIDENT NEAR 09N91W AS IT CONTINUES WESTWARD ALONG THE MONSOON TROUGH AXIS. ALTHOUGH THIS LOW LEVEL CIRCULATION CURRENTLY SEEMS TO BE WEAKENING...MODEL GUIDANCE HANGS ON TO THIS FEATURE THROUGH THE MIDDLE OF NEXT WEEK. A TROPICAL WAVE EXTENDS N FROM THIS EMBEDDED LOW PRES TO THE COAST OF GUATEMALA...AND IS ALSO LOSING IDENTITY...AND WILL LIKELY BE DROPPED FROM THE SURFACE ANALYSIS WITHIN THE NEXT COUPLE OF DAYS. SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS OBSERVED WITHIN 150 NM EITHER SIDE OF A LINE FROM 04N77W TO 10N91W. LOW LEVEL SCATTEROMETER WINDS INDICATE THAT THE MONSOON TROUGH TRANSITIONS TO AN ITCZ NEAR 08N94W...THEN WIGGLES BETWEEN 05N AND 08W AS IT CONTINUES W TO NEAR 08N118W...THEN TURNS SW TO BEYOND 04N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED FROM 03N TO 13N BETWEEN 98W AND 117W. ISOLATED MODERATE TO BRIEFLY STRONG CLUSTERS OF CONVECTION ARE OBSERVED FROM 04N TO 12N BETWEEN 117W AND 140W. ...DISCUSSION... AN UPPER TROUGH APPROACHING THE WESTERN SEABOARD OF THE CONUS CONTINUES SW INTO THE NW PORTION OF THE DISCUSSION AREA FROM 32N133W TO 28N140W. AN ASSOCIATED SURFACE FRONT IS DISSIPATING FROM 33N130W TO 29N140W. AN UPPER CYCLONE AT 16N132W IS MOVING W ACROSS THE DEEP TROPICAL PACIFIC JUST TO SE OF THIS UPPER RIDGE. AN UPPER ANTICYCLONE IS OVER EXTREME NORTHWESTERN OLD MEXICO... WITH AN UPPER RIDGE EXTENDING SW TO 21N140W. SOME CONVECTIVE DEBRIS MOISTURE IS TRAPPED UNDER THE RIDGE OVER THE GULF OF CALIFORNIA...AND IS SPREADING W ACROSS THE BAJA CALIFORNIA PENINSULA. SOME OF THE MOISTURE IS ALSO ADVECTED N...BUT EVAPORATES OVER SOUTHERN ARIZONA IN THE VERY DRY UPPER DOMINATING THE DISCUSSION AREA W OF A LINE FROM 23N110W TO 10N140W. AN UPPER CYCLONE IS OVER THE TEXAS/OLD MEXICO BORDER AT 28N100W WITH AN UPPER TROUGH EXTENDING SW ACROSS CENTRAL MEXICO TO THE PACIFIC COAST AT 22N105W...AND CONTINUING SW TO BASE NEAR 20N110W. A SECOND UPPER CYCLONE IS OVER BELIZE WITH AN UPPER TROUGH EXTENDING SW TO OVER THE E PACIFIC AT 13N93W. THESE UPPER TROUGHS ARE PENETRATING INTO THE NE PORTION OF BROAD ANTICYCLONIC FLOW THAT DOMINATES THE TROPICAL PACIFIC BETWEEN 92W AND 120W...ORIGINATING FROM THE ANTICYCLONE PREVIOUSLY MENTIONED OVER NW OLD MEXICO. SCATTERED MODERATE TO STRONG CONVECTION IS OBSERVED WITHIN 180 NM OF THE PACIFIC COAST OF MEXICO FROM 93W TO 98W...WITH STRONG NE UPPER FLOW ADVECTING THE DEBRIS MOISTURE SW OVER THE DISCUSSION AREA FROM 02N TO 20N BETWEEN 105W AND 115W. A SMALLER UPPER CYCLONE IS OVER THE EXTREME SW CARIBBEAN NEAR 10N82W WITH ITS ENVELOPE OF ANTICYCLONIC FLOW EXTENDING OVER THE DEEP TROPICS FROM 03N TO 13N BETWEEN 82W AND 90W. DENSE DEBRIS MOISTURE IS TRAPPED WITHIN THIS ENVELOP. AN UPPER TROUGH IS NOTED FROM 01N83W TO 12N79W AND IS PROGRESSING W WITH TIME. DIFFLUENCE E OF ITS AXIS IS SUPPORTING A LINE OF CONVECTION FROM THE PACIFIC AT 04N80W TO THE CARIBBEAN NEAR 11N79W. THE UPPER LEVELS APPEAR VERY DRY S OF 02N FROM 88W TO WELL BEYOND 140W... AND IS SUPPRESSING CONVECTION. ELSEWHERE AT THE LOW LEVELS...A SURFACE HIGH PRES IS CENTERED NEAR 30N127W AND ESTIMATED AT 1020 MB...WITH A RIDGE EXTENDING SE TO 18N110W. NORTHWESTERLY WINDS ARE AT 15 TO 20 KT NE OF THE RIDGE TO THE BAJA CALIFORNIA PENINSULA...ROUGHLY IN THE AREA N OF 29N E OF 118W...WITH COMBINED SEAS TO 8 FT IN THE NW SWELL. EXPECT THESE CONDITIONS TO SPREAD S AND W ON SUN INTO EARLY NEXT WEEK ACROSS THE WATERS N OF 27N E OF 120W. THE GRADIENT SHOULD RELAX SOME ON TUE WITH THE NW WINDS DIMINISHING TO 15 KT...BUT SEAS CONTINUING AT 4 TO 7 FT PRIMARILY DUE TO NW SWELL. BY THEN NE TRADES SW OF THE SURFACE RIDGE WILL INCREASE TO 15 TO 20 KT IN THE AREA FROM 18N TO 23N W OF 135W. GAP WINDS....NE TO E WINDS AT 20 TO 25 KT ARE NOTED IN THE AREA FROM 10N TO 12N TO E OF 92W INCLUDING THE GULF OF PAPAGAYO. ASSOCIATED SEAS HAVE BUILT TO 9 FT AS THE DEVELOPING EASTERLY SWELL ENCOUNTERS CROSS EQUATORIAL SW SWELL PROPAGATING THROUGH THESE WATERS. EXPECT THE AFFECTED AREA TO SHRINK ON SUN...FROM 10N TO 12N E OF 90W INCLUDING THE GULF OF PAPAGAYO...WITH THE E WINDS DIMINISHING TO 15 TO 20 KT AND SEAS SUBSIDING TO 5 TO 7 FT. BY MON THE ENHANCED WINDS SHOULD ONLY EFFECT THE GULF OF PAPAGAYO AND PULSE AT 15 TO 20 KT WITH SEAS AT 4 TO 6 FT. $$ NELSON