000 AXPZ20 KNHC 250940 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC SUN OCT 25 2009 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0915 UTC. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE EXTENDED FROM 11N81W TO 10N87W TO 12N111W TO 08N130W TO 08N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION FROM 08N TO 12N BETWEEN 93W AND 108W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM S AND 180 NM N OF AXIS BETWEEN 112W AND 126W. ...DISCUSSION... W OF 105W... A LARGE AND BROAD MIDDLE/UPPER LEVEL TROUGH IS CENTERED ACROSS THE CENTRAL U.S. WITH THE BASE EXTENDING SW THROUGH NORTHERN MEXICO TO THE EPAC ALONG 20N115W...WITH A NARROW TUTT LIKE TROUGH EXTENDING WNW TO 29N134W. THIS IS LEAVING A BROAD ZONE OF NW TO WLY FLOW ALOFT ACROSS THE AREA N OF ABOUT 15N E OF 130W AND INTO MEXICO. WATER VAPOR IMAGERY INDICATES STRONG SUBSIDENCE ACROSS THE MAJORITY OF THIS AREA...WHILE A NEW S/W TROUGH WAS SWINGING SW THROUGH THE BACKSIDE OF THE BROAD U.S. TROUGH...BRINGING A NARROW BAND OF MOISTURE AND INSTABILITY TO BAJA CALIFORNIA AND NW MEXICO N OF 27N. THE MEAN TROUGH ACROSS THE CENTRAL U.S. IS FORECAST TO MOVE LITTLE OVER THE NEXT FEW DAYS...WITH THE BASE OF THE TROUGH SAGGING VERY SLIGHTLY S AND SE ACROSS THE EASTERN PACIFIC. S OF THE BROAD NW TO W UPPER FLOW ACROSS THE EPAC...A NARROW UPPER LEVEL TROPICAL RIDGE EXTENDS FROM A HIGH NEAR 10N120W...W ALONG 10-12N THEN NW TO 24N136W... WHERE IT HAS BEEN AMPLIFYING N AND NW IN RESPONSE TO A CUTOFF UPPER LOW LOCATED ABOUT 10 DEGREES E OF THE BIG ISLAND OF HAWAII. THIS NARROW UPPER RIDGE IS LOCATED ALMOST DIRECTLY OVER THE ITCZ AND HAS BEEN VENTING ITCZ CONVECTION NICELY FOR THE LAST COUPLE OF DAYS. AT THE SURFACE A 1027 MB HIGH IS POSITIONED NEAR 35N136W AND IS NEARLY STATIONARY. A SURFACE TROUGH IS LOCATED FROM 11N113W TO 15N108W. A BROAD ZONE OF 20-25 KT NELY TRADES CONTINUED TO DOMINATE THE REGION...NOW CONFINED TO THE AREA W OF 120W EXTENDING S TO THE ITCZ. SEAS HERE WERE RUNNING 8 TO 10 FT IN MIXED NE WIND SWELL AND LONG PERIOD NW SWELL...WITH A FEW NARROW STRIPS OF HIGHER SEAS TO 11-12 FT W OF 130W AND JUST A FEW DEGREES N OF THE ITCZ...DUE TO STRONG WIND FLOW...LIKELY NEAR 30 KT. STRONG NNW FLOW WAS GRADUALLY SHIFTING S ALONG THE CENTRAL CALIFORNIA COAST LINE AND OFFSHORE WATERS...WITH INCREASING WINDS AND BUILDING SEAS EXPECTED TO SPREAD S OFF OF SOUTHERN CALIFORNIA AND BAJA DURING THE NEXT FEW DAYS. E OF 105W... A COMPLEX UPPER PATTERN OF TROUGH-RIDGE-TROUGH FROM CENTRAL AMERICA NE TO CUBA WAS YIELDING A GENERAL DIFFLUENT UPPER WIND FLOW ACROSS MUCH OF THE FAR ERN EPAC...WHICH ALSO REMAINED ACTIVE CONVECTIVELY. THESE CONVECTIVELY FAVORABLE CONDITIONS ALOFT ARE FORECAST TO BECOME LESS FAVORABLE DURING THE NEXT 24 HOURS ACROSS MUCH OF THIS AREA. AT LOW TO MID LEVELS...AN ELONGATED MONSOONAL CIRCULATION PERSISTED FROM THE FAR WRN CARIBBEAN SW ACROSS CENTRAL AMERICA TO ABOUT 11N96W. THIS WAS REFLECTED IN THE SURFACE FLOW ACROSS THE AREA...WHICH AN OVERNIGHT QUIKSCAT PASS DEPICTED AS GENERALLY LIGHT AND VARIABLE N OF THE ITCZ...AND S TO SW ON THE S SIDE OF THE ITCZ. SEVERAL PESKY LOWS CONTINUE EMBEDDED WITHIN THIS LARGER CYCLONIC FLOW AND WERE DEPICTED BY QUIKSCAT OVERNIGHT...ONE NEAR 12N93.5W AND ANOTHER NEAR 09N86.5W...WHILE A THIRD WAS IN THE CARIBBEAN ALONG THE E COAST OF NICARAGUA. WINDS NEAR 20 KT WERE INDICATED ACROSS THE S AND SE QUADRANTS OF THESE LOWS IN THE PACIFIC....WHERE SEAS WERE NEAR 8 FT. SOME OF THE COMPUTER MODELS ARE SHOWING THE POTENTIAL FOR BETTER ORGANIZATION OF THE WESTERNMOST LOW BY MID WEEK...IN THE VICINITY OF 105W. $$ STRIPLING