000 AXPZ20 KNHC 082145 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 2205 UTC SUN OCT 08 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 2130 UTC. ...SPECIAL FEATURES... A 1006 MB LOW IS LOCATED NEAR 12N118W AND IS NEARLY STATIONARY. STRONG CONVECTION IS LOCATED WITHIN 180 NM OF THE CENTER OVER THE NE SEMICIRCLE. THIS SYSTEM MAY DEVELOP INTO A TROPICAL CYCLONE WITHIN THE NEXT 36 HOURS. A STATIONARY 1006 MB LOW IS LOCATED NEAR 12N127W. STRONG CONVECTION HAS FLARED THIS AFTERNOON WITHIN 120 NM OF THE CENTER OVER THE EASTERN SEMICIRCLE. THIS SYSTEM HAS THE POTENTIAL TO BECOME A TROPICAL CYCLONE WITHIN THE NEXT 36 HOURS. ...TROPICAL WAVES... A TROPICAL WAVE IS LOCATED ALONG 96W N OF 4N INTO MEXICO AND IS MOVING W 10 TO 15 KNOTS. LITTLE CONVECTIVE ACTIVITY IS ASSOCIATED WITH THIS FEATURE. ...ITCZ... ITCZ AXIS IS CENTERED ALONG 8N78W 9N84W 10N95W 10N106W 13N115W 11N122W 12N127W 10N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS LOCATED WITHIN 180 NM S OF THE AXIS BETWEEN 78W-82W...AND 85W-88W. SCATTERED MODERATE TO STRONG CONVECTION IS LOCATED WITHIN 240 NM EITHER SIDE OF THE AXIS BETWEEN 111W AND 115W. NUMEROUS STRONG CONVECTION WITHIN 180 NM OF 1006 MB LOW CENTER NEAR 12N118W. NUMEROUS STRONG CONVECTION WITHIN 120 NM OF 1006 MB LOW CENTERED NEAR 12N127W. ...DISCUSSION... N OF 20N... UPPER LOW IS CENTERED OVER SOUTHERN CALIFORNIA WITH ASSOCIATED TROUGH AXIS TRAILING TO THE SW THROUGH 26N137W. UPPER RIDGE BUILDING ALONG 138W N OF THE AREA AND AHEAD OF DEEP TROUGH OVER THE N CENTRAL PACIFIC...IS PROVIDING DRY NW FLOW OVER THE FORECAST AREA N OF THE TROUGH AXIS. S OF THE AXIS...MODERATE TO STRONG WLY UPPER FLOW PERSISTS BETWEEN THE TROUGH AND RIDGING TO THE S. MORNING QUIKSCAT IMAGERY SHOWS MODERATE NE TRADES ON SOUTHERN PERIPHERY OF BOUNDARY LAYER RIDGE CENTERED TO THE N. WEAK VORTICITY N OF HAWAII WILL MOVE E...TO THE S OF THE UPPER RIDGE...AND REINFORCE THE TROUGH OVER THE NEXT 48 HOURS. MEANWHILE SURFACE HIGH PRESSURE WEAKENS IN THIS AREA AHEAD AS TROUGH IN CENTRAL PACIFIC MOVES TO THE N. THIS WILL ALLOW WINDS TO SUBSIDE THROUGH MID WEEK...DEPENDENT OF COURSE ON SURFACE LOW DEVELOPMENT TO THE SOUTH. FROM 10N TO 20N... UPPER ANTICYCLONIC CIRCULATIONS NOTED ROUGHLY NEAR 10N138W AND 12N116W. THE EASTERNMOST SYSTEM IS PROVIDING CONTINUOUS EXHAUST TO CONVECTION BELOW AND IS AIDING DEVELOPMENT OF 1006 MB SURFACE LOW NEAR 12N118W. THE WESTERNMOST SYSTEM IS ENTRAINING DRY AIR INTO THE MID LEVELS FROM THE N AND NW SHEAR OVER THE CIRCULATION NEAR 12N127W. CONVECTION IS FLARING AGAIN AROUND THIS SYSTEM CURRENTLY...BUT UPPER LEVEL TRENDS HAVE NOT BEEN FAVORABLE OVER THE PAST 12 HOURS FOR THIS SYSTEM. SUBSIDENT NLY FLOW IS ALSO IMPEDING MOST CONVECTIVE GROWTH BETWEEN 94W AND 110W. FURTHER E...ANOTHER UPPER ANTICYCLONE IS AIDING CONVECTION E OF 90W TO THE CENTRAL AMERICAN COAST. MAIN FORECAST ISSUE CONTINUES TO BE THE DEVELOPMENT OF THE SURFACE LOWS MENTIONED IN SPECIAL FEATURE SECTIONS. GLOBAL MODELS CONSISTENTLY SHOW ONLY WEAK DEVELOPMENT OF THESE SYSTEMS WITH AN EVENTUAL TURN MORE NELY S OF THE UPPER TROUGH AXIS BEFORE WEAKENING. BEFORE THIS HAPPENS...THERE REMAINS SOME POTENTIAL FOR AT LEAST THE EASTERNMOST OR EVEN BOTH TO FORM INTO TROPICAL DEPRESSIONS OVER THE NEXT DAY OR TWO. THE OTHER FORECAST ISSUE CONCERNS THE GULF OF TEHUANTEPEC. SHIP OBSERVATIONS AND SURFACE OBSERVATIONS FROM MMIT AND MMMT SHOW MUCH WEAKER FLOW THAN PREVIOUS DAYS. HOWEVER...EARLY MORNING QUIKSCAT PASS SHOWED THIN RIBBON OF 20 KT WINDS. EXPECT THIS TO CONTINUE TO WEAKEN THROUGH TONIGHT. LOOKING AHEAD...GAP WINDS WILL REMAIN RELAXED UNTIL THE LATTER PART OF NEXT WEEK...WHEN A STRONG FRONT WILL ENTER THE SW GULF OF MEXICO. S OF 10N... QUIKSCAT SHOWS GENERALLY MODERATE S TO SELY FLOW ACROSS THE EQUATOR. GFS IS SHOWING HINT OF SLIGHT INCREASE IN WINDS AND SEAS S OF ITCZ BETWEEN 94W AND 115W STARTING MID WEEK PROBABLY DUE TO HIGH PRESSURE BUILDING S OF THE EQUATOR. $$ CHRISTENSEN