000 AXPZ20 KNHC 151542 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC WED AUG 15 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 FEATURE... TROPICAL STORM HECTOR IS CENTERED NEAR 17.8 115.2W AT 15/1500 UTC MOVING N OR 360 DEG AT 4 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH GUSTS TO 45 KT. HECTOR WILL CONTINUE TO BE AFFECTED BY 15-20 KT OF EAST-SOUTHEASTERLY SHEAR DURING THE NEXT COUPLE OF DAYS AS IT MOVES SLOWLY TO THE NORTH ACROSS A GRADUAL COOLING OF SURFACE WATERS. DUE TO THE SHEAR...MOST OF THE DEEP CONVECTION IS DISPLACED TO THE SW WITH SATELLITE IMAGERY SHOWING NUMEROUS MODERATE ISOLATED STRONG CONVECTION WITHIN 240 NM SW SEMICIRCLE OF HECTOR. BASED ON THE OFFICIAL INTENSITY FORECAST...HECTOR IS EXPECTED TO WEAKEN TO A DEPRESSION THU MORNING AND TO A REMNANT LOW FRI MORNING. SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC FOR MORE DETAILS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH EXTENDS FROM 07N78W TO 10N88W TO EMBEDDED LOW PRES AT 08N95W THEN CONTINUES W OF T.S. HECTOR FROM 13N120W TO 10N134W. ITCZ AXIS IS FROM 10N134W TO BEYOND 08N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED FROM 03N TO 07N E OF 81W TO THE COAST OF COLOMBIA. SIMILAR CONVECTION IS WITHIN 150 NM S SEMICIRCLE OF LOW PRES NEAR 08N95W. SCATTERED MODERATE CONVECTION CAN BE FOUND FROM 04N TO 07N BETWEEN 84W AND 90W... FROM 10N TO 18N BETWEEN 103W AND 108W...AND FROM 11N TO 13N BETWEEN 111W AND 118W. ...DISCUSSION... ALOFT...AN UPPER CYCLONE IS NOTED JUST N OF THE AREA AT 35N132W WITH AN UPPER TROUGH EXTENDING SE INTO THE FORECAST AREA TO NEAR 27N127W. AN UPPER ANTICYLONE IS CENTERED JUST W OF THE FORECAST REGION AT 21N143W WITH A RIDGE EXTENDING E THEN NE TO NEAR 30N120W. ANOTHER ANTICYLONE IS NOTED ALONG THE PACIFIC COAST OF MEXICO NEAR 23N106W WITH A RIDGE TO THE S AND SW TO NEAR 11N118W. UPPER DIFFLUENCE ASSOCIATED WITH THIS SYSTEM IS HELPING TO INDUCE CONVECTION FROM 10N TO 18N BETWEEN 103W AND 108W...AND FROM 11N TO 13N BETWEEN 111W AND 118W. AT THE SAME TIME...THIS SYSTEM KEEPS HECTOR AS A SHEARED CYCLONE. AN ILL- DEFINED UPPER LEVEL CYCLONE NEAR 19N124W HAS A TROUGH STRETCHING MAINLY TO THE NE TO NEAR 24N121W. NE UPPER LEVEL FLOW DOMINATES MOST OF THE FORECAST WATERS E OF 110W WHILE ELY FLOW ALOFT IS NOTED S OF 10N. A SURFACE LOW IS EMBEDDED IN THE MONSOON TROUGH NEAR 08N95W. LATEST SATELLITE IMAGERY SHOWS SCATTERED MODERATE CONVECTION MAINLY TO THE S AND SW OF LOW CENTER WITH NARROW BANDS OF LOW CLOUDS INDICATING THE CYCLONIC CIRCULATION TO THE N. THE MOST RECENT SCATTEROMETER DATA PROVIDED OBSERVATIONS OF 15-20 KT SW TO W WINDS TO THE S OF THE LOW CENTER AND ESPECIALLY NEAR THE CONVECTIVE ACTIVITY. THIS WEAK LOW PRES WILL MOVE MAINLY WWD ALONG THE MONSOON TROUGH. NO TROPICAL CYCLONE DEVELOPMENT IS EXPECTED. THE ENVELOPE OF CYCLONIC 20 KT OR GREATER WINDS ASSOCIATED WITH TROPICAL STORM HECTOR EXTENDS ONLY ABOUT 90 NM OVER THE N SEMICIRCLE...BUT EXTENDS ABOUT 480 NM OVER THE S SEMICIRCLE MOSTLY DUE TO STRONG SOUTHWESTERLY MONSOONAL FLOW. PRES GRADIENT BETWEEN HECTOR AND HIGHER PRES OVER CENTRAL MEXICO IS RESULTING IN AREA OF 20 TO 25 KT SE TO S WINDS FROM 18N TO 24N BETWEEN 106W AMD 109W. THESE WINDS ALONG WITH LONG PERIOD SLY SWELLS ARE ALLOWING SEAS TO BUILD TO NEAR 8 FT ACROSS THE SOUTHERN PART OF THE SEA OF CORTEZ. CICESE...THE MONITORING NETWORK OF SEA LEVEL LOCATED IN ENSENADA NORTHERN BAJA CALIFORNIA ALSO CONFIRMS THE INCREASING SEAS IN THIS AREA. IN ADDITION...A LOW PRES SITUATED NEAR THE ARIZONA/SOUTHERN CALIFORNIA BORDER IS PRODUCING SE TO S WINDS 0F 20 KT WITH OCCASIONALLY 25 KT ACROSS THE SEA OF CORTEZ N OF 29N WITH SEAS TO AROUND 6 FT. THESE MARINE CONDITIONS ARE FORECAST TO GRADUALLY DIMINISH OVER THE NEXT 24 HOURS. LONG PERIOD SW SWELLS ARE NOTED OVER THE AREA S OF 21N BETWEEN 97W AND 119W AND ALSO S OF 07N BETWEEN 82W AND 88W...WITH THE SWELL TRAIN INTERRUPTED BY THE GALAPAGOS ISLANDS. THESE SWELLS ARE EXPECTED TO SUBSIDE OVER THE NEXT COUPLE OF DAYS. $$ GR