000 AXPZ20 KNHC 010311 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC THU SEP 31 2009 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0300 UTC. ...SPECIAL FEATURE... A LARGE AND BROAD LOW AND MID LEVEL CYCLONIC CIRCULATION LOCATED ABOUT 500 NM SW OF THE SRN TIP OF BAJA CALIFORNIA COVERS THE AREA FROM ABOUT 16N TO 23N BETWEEN 108W AND 120W. A 1004 MB SURFACE LOW IS ANALYZED WITHIN THIS AREA TO BE NEAR 20N116W ...MOVING WNW 10 KT. LAST VISIBLE IMAGERY SHOWED POORLY ORGANIZED BANDING ASSOCIATED WITH THE LOW. IR IMAGERY IS SHOWING SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 30 NM EITHER SIDE OF A LINE FROM 24N112W TO 24N115W...AND WITHIN 45 NM OF 22N113W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF 20N116W. THIS SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL DEPRESSION OVER THE NEXT 48 HOURS. ...TROPICAL WAVE... A TROPICAL WAVE IS ALONG 105W FROM 6N-15N MOVING W ABOUT 16 KT. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF THE WAVE FROM 13N TO 15N. ...ITCZ... AXIS IS CENTERED ALONG 8N78W TO 9N90W TO 11N100W TO 14N110W... THEN RESUMES AT 15N114W TO 11N125W TO 11N140W. SCATTERED STRONG CONVECTION IS WITHIN 45 NM EITHER SIDE OF THE AXIS BETWEEN 114W-120W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS WITHIN 30 NM EITHER SIDE OF THE AXIS BETWEEN 125W-129W. SCATTERED MODERATE CONVECTION IS WITHIN 60 NM S OF THE AXIS BETWEEN 129W-132W. ...DISCUSSION... A DEEP LAYER TROUGH ENTERS THE REGION OVER THE NE PORTION OF THE AREA THROUGH 32N125W...AND EXTENDS SW TO AN ELONGATE CYCLONIC CIRCULATION NEAR 30N129W. THE TROUGH CONTINUES SW FROM THIS CIRCULATION TO W OF THE AREA AT 23N140W. THE BASE OF THIS TROUGH IS VERY BROAD AND COVERS THE NRN PORTION AND MUCH OF THE CENTRAL PORTION OF THE AREA. TO ITS SE...A 50-60 KT JET STREAM BRANCH ENTERS THE REGION THROUGH 22N140W...AND EXTENDS NE TO 25N130W TO 30N122W TO NRN BAJA AND SRN CALIFORNIA WHERE IT MERGES WITH ANOTHER JET THAT DIVES SEWD INTO THE SRN CALIFORNIA FROM THE FAR NRN PACIFIC. THE UPPER TROUGH WILL PUSH E TO THE N OF 30N...AND MOVE LITTLE S OF 30N OVER THE NEXT FEW DAYS AS A STRONG ANTICYCLONE REMAINS TO ITS SE. OVER THE ERN SECTION...A WELL PRONOUNCED UPPER LEVEL ANTICYCLONE IS OVER WRN MEXICO NEAR 23N106W...AND IS SERVING AS A BLOCKING FEATURE ACROSS THIS PORTION OF THE AREA. A RIDGE EXTENDS SW FROM THE ANTICYCLONE TO ACROSS THE LOW DESCRIBED ABOVE NEAR 20N116W ...AND CONTINUES SW TO A COL REGION NEAR 12N135W. FROM THERE THE RIDGE EXTENDS TO FAR W OF THE AREA TO ANOTHER UPPER ANTICYCLONE. TO THE S OF THE ANTICYCLONE AND RIDGE...A DIFFLUENT PATTERN IS HELPING TO VENTILATE CONVECTION ALONG THE ITCZ GENERALLY BETWEEN 104W AND 121W...WHILE THE WRN PERIPHERY OF THE ANTICYCLONE INDUCES OUTFLOW MAINLY TO THE N OF THE LOW NEAR 20N116W. SATELLITE WATER VAPOR IMAGERY SHOWS RATHER DRY AND STABLE CONDITIONS TO THE NW OF THE JET STREAM AND BETWEEN THE RIDGE AND THE JET STREAM E OF 126W. AN AREA OF BROAD AND MODEST LOW TO MID LEVEL CYCLONIC TURNING IS NOTED OVER THE FAR ERN PORTION OF THE AREA FROM 3N TO 14N BETWEEN 85W AND 108W...INCLUDING THE ENVIRONMENT ABOVE THE TROPICAL WAVE ALONG 105W. MODERATE SUBSIDENCE MOSTLY PREVAILS HERE KEEPING DEEP CONVECTION TO A MINIMUM. ONLY ISOLATED SHOWERS AND TSTMS MOVING W ARE SEEN N OF THE ITCZ AND E OF THE TROPICAL WAVE 92W. AT THE SURFACE...A HIGH PRES RIDGE EXTENDS SE INTO THE REGION THROUGH 32N131W AND SE TO NEAR 26N119W. A WEAK TROUGH IS ALONG 136W FROM 10N-15N MOVING W 8 KT. ISOLATED SHOWERS ARE WITHIN 30 NM OF THE TROUGH. GULF OF TEHUANTEPEC N-NE WINDS TO 20 KT ARE WITHIN 75 NM FROM THE COAST. THESE WINDS ARE FORECAST TO DIMINISH IN ABOUT 24 HOURS AS THE PRES GRADIENT OVER INTERIOR OF MEXICO WEAKENS. REGIONAL SEAS CONTINUE TO BE DOMINATED BY MODERATE PERIOD SRN HEMISPHERE SE SWELL...AND LONGER PERIOD NW AND SSW SWELL. SEAS UP TO ABOUT 9 OR 10 FT ARE FORECAST BY WAVE MODEL GUIDANCE TO PROPAGATE NWD OVER PORTIONS OF THE FAR SRN WATERS THROUGH THE NEXT 48 HOURS. $$ AGUIRRE