000 AXPZ20 KNHC 100332 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT OCT 10 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 0315 UTC. ...SPECIAL FEATURE... A BROAD AND ELONGATED ARE OF LOW PRES LOCATED OVER THE FARE ERN PORTION OF THE AREA FROM 12N TO 19N BETWEEN 100W AND 109W IS REVEALING A MORE DEFINED LOW PRES CENTER NEAR 18N106W...OR ABOUT 150 NM SW OF MANZANILLO MEXICO. SATELLITE VISIBLE IMAGERY FROM THROUGHOUT THE DAY HAVE SHOWN THAT THE CLOUD PATTERN OF THIS AREA HAS ACQUIRED MORE OF A DEFINED CYCLONIC SIGNATURE WITH A NOTICEABLE 90 NM WIDE BANDING FEATURE CONSISTING OF SCATTERED TO NUMEROUS STRONG CONVECTION FROM 12N101W TO 16N103W TO 18N104W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION IS ELSEWHERE FROM 15N TO 19N BETWEEN 100W AND 106W...WITH THE STRONGEST OF THIS CONVECTION BETWEEN ACAPULCO AND MANZANILLO. HEAVY RAINFALL CAN BE EXPECTED WITHIN THIS AREA OVER THE NEXT 48 HOURS AS THIS CONVECTION MOVES VERY LITTLE AND REMAINS UNDER AN UPPER LEVEL DIFFLUENT DUE TO A DEEP LAYER TROUGH DESCRIBED BELOW. WITHIN 150 NM E SEMICIRCLE OF THE LOW WINDS OF 20-25 KT ARE OCCURRING WITH POSSIBLE GUSTS TO 30 KT IN THE HEAVIER SQUALLS AND TSTMS ASSOCIATED WITH THE BANDING FEATURE. THIS SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL CYCLONE OVER THE NEXT 48 HOURS AS IT TRACKS NNE. ...TROPICAL WAVE... A TROPICAL WAVE ENTERED THE DISCUSSION TODAY...AND WAS ALONG 87W N OF 5N AT 0000 UTC MOVING W ABOUT 13 KT. CONVECTION ASSOCIATED WITH THIS WAVE IS DESCRIBED BELOW UNDER ITCZ. ...ITCZ... THE ITCZ AXIS WAS CENTERED ALONG 9N85W TO 9N93W TO 12N104W TO 12N113W TO 12N126W TO 9N140W. SCATTERED STRONG CONVECTION WAS WITHIN 120 NM S OF THE AXIS BETWEEN 85W-90W. SCATTERED MODERATE TO STRONG CONVECTION WAS WITHIN 180 NM S OF THE AXIS BETWEEN 100W-106W. SCATTERED MODERATE/ISOLATED STRONG CONVECTION WAS WITHIN 180 NM S OF THE AXIS BETWEEN 130W-135W...AND WITHIN 120 NM S OF THE AXIS BETWEEN 106W-110W. SCATTERED MODERATE CONVECTION IS WITHIN 30 NM OF THE AXIS BETWEEN 125W-130W. ...DISCUSSION... A MID/UPPER LEVEL TROUGH THAT STRETCHES FROM THE CENTRAL U.S SSW TO FAR WRN MEXICO NEAR 21N105W. TO THE SW OF THE TROUGH IS A MID/UPPER LEVEL ANTICYCLONIC CIRCULATION CENTERED NEAR 17N116W... WITH A RIDGE EXTENDING W FROM THE ANTICYCLONE TO W OF THE AREA AT 14N140W. A JET STREAM BRANCH RIDING ACROSS THE TOP OF THE RIDGE AS SEEN IN WATER VAPOR IMAGERY WILL CONTINUE TO ADVECT UPPER LEVEL MOISTURE IN THE FORM OF SCATTERED THIN CIRRUS ACROSS EWD ACROSS NRN AND CENTRAL BAJA CALIFORNIA AND TOWARDS FAR NW MEXICO. A SHARPENING DEEP LAYER TROUGH WAS DIGGING SEWD TO THE NW OF THE ANTICYCLONE WITH ITS AXIS STRETCHING FROM 32N129W SW TO 27N135W TO 22N138W. MODERATE SUBSIDENCE LEADING TO RATHER STABLE ENVIRONMENTAL CONDITIONS ALONG AND W OF THIS TROUGH. OVER THE FAR ERN PORTION OF THE AREA...A MID/UPPER LEVEL CYCLONIC CIRCULATION MOVING W 15 KT WAS JUST S OF GUATEMALA NEAR 14N92W. THIS LOW WAS ENHANCING SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITH THE TROPICAL WAVE ALONG 87W AS AS OVER GUATEMALA AND FAR SE MEXICO . A SURFACE RIDGE ENTERS THE REGION THROUGH 32N135W AND EXTENDS SE TO NEAR 22N118W. A TIGHT PRES GRADIENT E OF THE RIDGE IS ALLOWING FOR NW WINDS OF 20 KT FROM N OF 22N AND E OF 118W TO THE COAST OF BAJA CALIFORNIA. HOWEVER...THE RIDGE IS FORECAST TO WEAKEN WITHIN THE NEXT 24-36 HOURS AS A COLD FRONT APPROACHES THE FAR NW CORNER OF THE REGION. OVER THE SRN PORTION...A TROUGH EXTENDS ALONG 133W FROM 8N TO 15N MOVING W 10 KT...AND IS ENHANCING CONVECTION ALONG THE ITCZ AS DESCRIBED ABOVE. TO THE N OF THE TROUGH...NE TRADES OF 20 TO 25 KT WITH SEAS OF 8 TO 10 FT WERE NOTED FROM 2N TO 20N W OF 115W. THESE CONDITIONS ARE FORECAST TO DIMINISH BY 48 HOURS. A COLD FRONT...AS STATED ABOVE...IS FORECAST TO BE JUST NW OF THE AREA IN 24 HOURS...THEN MOVE TO ALONG A LINE FROM 30N136W TO 26N140W IN 48 HOURS. S TO SW WINDS WILL INCREASE TO 20 KT AHEAD OF THE FRONT WITH SEAS TO 8 FT. NW TO N WINDS BEHIND THE FRONT WILL INCREASE TO 20 KT WITH SEAS BUILDING 8 TO 11 FT IN NW SWELL. $$ AGUIRRE