000 AXPZ20 KNHC 021024 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SAT JUL 01 2006 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1000 UTC. ...SPECIAL FEATURE... LOW PRES NEAR 11N131W MOVING W ABOUT 16 KT REMAINS ALONG THE NORTHERN EXTENT OF THE ITCZ. EARLIER THIS MORNING CONVECTION HAD WANED...BUT HAS RECENTLY INCREASED IN COVERAGE WEST OF CENTER. IT IS COMPOSED OF SCATTERED STRONG INTENSITY WITHIN 180 NM SOUTHWEST AND WEST QUADRANTS OF LOW. OVERALL...THE CLOUD PATTERN OF THE SYSTEM DOES SHOW A CURVATURED TYPE PATTERN TO THE CLOUDS AS OBSERVED ON SATELLITE IMAGERY. HOWEVER...THIS SYSTEM IS APPROACHING AN AREA OF STABLE AIR TO THE WEST AS EVIDENCED BY A LARGE AREA OF STRATOCUMULUS CLOUDS PRESENT THERE. IN ADDITION THE SYSTEM IS APPROACHING AN AREA OF MODERATE SOUTHWEST SHEAR MAKING ITS ENVIRONMENT UNFAVORABLE FOR DEVELOPMENT. LOW PRES NEAR 12N121W MOVING W 15 KT. SMALL CIRCULATION CENTER ABOUT 60 NM WIDE WITH LARGE CLUSTER OF SCATTERED STRONG CONVECTION FROM 11N-13N BETWEEN 120.5W-123W. THIS SYSTEM ALSO ENTERING AN ENVIRONMENT NOT TOO FAVORABLE FOR DEVELOPMENT. ...TROPICAL WAVES... TROPICAL ALONG 85W NORTH OF 5N IS MOVING W 15-20 KT. ONLY ISOLATED MODERATE CONVECTION IS NOTED WITHIN 60 NM OF THE WAVE AXIS FROM 5N-8N. TROPICAL WAVE ALONG 115W FROM 5N TO 15N IS MOVING W AT 15 KT. CONVECTION IS MAINLY ITCZ-RELATED AS DESCRIBED BELOW. HOWEVER... THERE IS SOME EVIDENCE OF A SURFACE TO LOW LEVEL CIRCULATION NEAR 11N116W. UPPER LEVEL NORTHERLY SHEAR IS PREVENTING THIS WAVE FROM DEVELOPING. NO FURTHER DEVELOPMENT IS EXPECTED. TROPICAL WAVE JUST WEST OF THE AREA ALONG 141W FROM 5N TO 15N IS MOVING W 15 KT. STRONG SOUTHWEST UPPER LEVEL SHEAR ENVIRONMENT NOT ALLOWING THIS WAVE FROM DEVELOPING. ONLY SCATTERED SCATTERED STRONG CONVECTION IS SEEN WITHIN 30 NM OF 8N141.5W. ..ITCZ... INTERTROPICAL CONVERGENCE ZONE AXIS IS CENTERED ALONG 9N84W 8N95W 11N115W 12N125W 12N134W 11N140W. SCATTERED STRONG CONVECTION IS WITHIN 60 NM EITHER SIDE OF THE ITCZ BETWEEN 107W-109W...AND ALSO BETWEEN 114W-116W. SCATTERED MODERATE TO STRONG CONVECTION EXISTS FROM 8N-11N WEST OF 135W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS SEEN WITHIN 60 NM EITHER SIDE OF THE ITCZ BETWEEN 96W-100W. ...DISCUSSION... MID TO UPPER SHORTWAVE TROUGH NORTHWEST OF LINE 32N125W 22N140W IS DAMPENING OUT WITH TIME AS IT PULLS NORTHEAST OF THE AREA WITH TIME. MID/UPPER LEVEL ANTICYCLONIC FLOW CONTINUES TO DOMINATE THE VAST MAJORITY OF THE AREA WITH A STATIONARY ANTICYCLONIC CENTER NEAR 13N118.5W. A MID/UPPER LEVEL RIDGE EXTENDS NORTHEAST FROM 19N127W THROUGH 25N124W TO BEYOND 32N121W TO SOUTHERN CALIFORNIA WHERE IT FLATTENS OUT. ASSOCIATED BROAD AREA OF UPPER LEVEL DIFFLUENCE CONTINUES TO AID CONVECTION ALONG THE ITCZ BETWEEN 110W-125W. THE RESULTANT DEBRIS MOISTURE PLUME SPREADS NORTHWARD UNDER THE RIDGE TO ALONG 21N GENERALLY BETWEEN 115W-135W. THE AFOREMENTIONED RIDGE BREAKS DOWN BEGINNING LATE TUE OF NEXT WEEK AND THROUGH FRI. RIDGE DOES NOT COMPLETELY GO AWAY AS IT IS REPLACED BY NEW RIDGE THAT BUILDS EAST INTO THE AREA STATED ABOVE. THE DEBRIS MOISTURE SPREADS EAST AND NORTHEAST AROUND THE CIRCULATION OF A NEW DEVELOPED MID/UPPER NEARLY STATIONARY UPPER LEVEL CYCLONE NEAR 18N106W...THEN ACROSS SOUTHEASTERN MEXICO AND CENTRAL AMERICA...AND NORTHWARD INTO MUCH OF THE WESTERN AND CENTRAL GULF OF MEXICO. THE LOW IS EMBEDDED IN A STATIONARY NEGATIVELY TILTED UPPER TROUGH THAT RUNS NORTHWEST TO SOUTHEAST ALONG MEXICO FROM 29N113W THROUGH THE CYCLONE NEAR 18N106W AND SOUTHEAST TO NEAR 11N100.5W. ASSOCIATED DIFFLUENCE IS AIDING ITCZ CONVECTION EAST OF 100W. STRONG UPPER LEVEL SOUTHWEST WINDS MARKING A JET STREAM WILL MOVE INTO THE AREA NEXT WEEK ALONG THE NORTHERN BOUNDARY OF THE AREA NORTH OF 26N AND WEST OF 120W. SOUTH OF THE ITCZ EAST OF 105W THE MID/UPPER LEVEL FLOW BECOMES NORTHERLY WITH TWO SMALL UPPER LEVEL CYCLONIC CIRCULATIONS NOTED ON WATER VAPOR IMAGERY TO BE NEAR 1N92W AND 2N78W. MOISTURE IS JUST ABOUT NON-EXISTENT HERE WITH ONLY ISOLATED SHOWERS AND THUNDERSTORMS NOTED AS MODERATE TO STRONG SUBSIDENCE AND ASSOCIATED DRY AIR CAPS THIS AREA. AT THE SURFACE A RIDGE EXTENDS INTO THE DISCUSSION AREA THROUGH 32N132W...AND EXTENDS THROUGH 25N125W TO 20N119W. HIGH PRESSURE COVERS THE AREA NORTH OF 17N AND WEST OF 122W. GAP WINDS...WINDS HAVE DECREASE TO BELOW 20 KT IN THE GULF OF TEHUANTEPEC...BUT CONTINUE NE AT 20 KT ACROSS THE GULF OF PAPAGAYO AND ARE EXPECTED TO DIMINISH IN ABOUT 48 HOURS. $$ AGUIRRE