000 AXPZ20 KNHC 140930 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC WED OCT 14 2015 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 0900 UTC. ...SPECIAL FEATURES... A TROPICAL WAVE WAS ANALYZED FROM 15N112W TO 1008 MB LOW PRES NEAR 10N112W ALONG THE MONSOON TROUGH AXIS. THE WAVE HAS BEEN MOVING W AROUND 12 KT OVER THE LAST 24 HOURS. SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION WAS NOTED WEST OF THE TROPICAL WAVE AND WITHIN 180 NM N OF THE MONSOON TROUGH. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO BECOME MORE CONDUCIVE FOR THE DEVELOPMENT OF A TROPICAL DEPRESSION LATER THIS WEEK OR THIS WEEKEND. PLEASE SEE THE LATEST NHC TROPICAL WEATHER OUTLOOK UNDER AWIPS/WMO HEADERS MIATWOEP/ABPZ20 KNHC FOR MORE DETAILS. ...TROPICAL WAVES... A TROPICAL WAVE WAS ANALYZED ALONG 92W/93W N OF 08N TO THE MEXICO/GUATEMALA BORDER. THE WAVE HAS BEEN MOVING W AROUND 15 KT. SCATTERED MODERATE WITHIN 90 NM N AND 180 NM S OF AXIS BETWEEN 90W AND 100W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... MONSOON TROUGH FROM 10N85W TO 08N95W TO LOW PRES NEAR 10N112W TO 07N118W. CONVECTION PATTERNS ALONG THE MONSOON TROUGH ARE RELATED TO THE AFOREMENTIONED TROPICAL WAVE FEATURES. ...DISCUSSION... N OF 15N E OF 120W INCLUDING THE GULF OF CALIFORNIA...A WEAK PRESSURE PATTERN HAS SET UP OVER THE REGION WITH WEAK 1015 MB HIGH PRES CENTERED NEAR 25N117W. SHIP OBSERVATIONS AND ASCAT SATELLITE DATA SHOW GENTLE TO MODERATE NORTHERLY FLOW ACROSS THE GULF OF CALIFORNIA AND OFF THE BAJA CALIFORNIA PENINSULA...WITH NE WINDS FARTHER SOUTH. A RECENT ALTIMETER SATELLITE PASS INDICATED SEAS GENERALLY 5 TO 6 FT OFF BAJA...INDICATING THE PREVALENT NW SWELL OVER THE PAST COUPLE OF DAYS HAS SUBSIDED. NW WINDS OFF BAJA AND OVER CENTRAL AND SOUTHERN GULF OF CALIFORNIA WILL INCREASE SLIGHTLY LATE TODAY AND TONIGHT AS A TROUGH DEEPENS OVER NW MEXICO...PARTLY DUE TO A WEAKENING UPPER LOW MOVING NE ACROSS SOUTHERN CALIFORNIA. THIS PATTERN WILL BE SHORT LIVED...LEAVING GENTLE TO MODERATE NW FLOW IN PLACE THROUGH THE REMAINDER OF THE WEEK. GULF OF TEHUANTEPEC...THE TROPICAL WAVE ALONG 92/93W WILL PASS THROUGH THE GULF OF TEHUANTEPEC TODAY. THE INCREASED PRESSURE GRADIENT BETWEEN THIS WAVE AND HIGHER PRESSURE OVER NE MEXICO WILL DRIVE STRONG TO NEAR GALE FORCE N-NE WINDS THROUGH CHIVELA PASS THIS MORNING. WINDS WILL ABATE SLIGHTLY BY AFTERNOON AFTER THE NOCTURNAL DRAINAGE FLOW WANES. THE TIGHT GRADIENT WILL PERSIST ALLOWING MINIMAL GALE FORCE WINDS BY EARLY THU MORNING CONTINUING THROUGH THU EVENING...WITH SEAS BUILDING TO 12 FT. LOOKING AHEAD...GLOBAL MODELS INDICATE THIS PATTERN WILL CONTINUE THROUGH THE REMAINDER OF THE WEEK...FAVORING GALE FORCE WINDS DURING THE OVERNIGHT AND EARLY MORNING HOURS. S OF 15N E OF 110W...TOGA BUOYS AND RECENT ASCAT DATA INDICATE 10 TO 15 SW WINDS ACROSS THE REGION SOUTH OF THE MONSOON TROUGH...PROVIDING ENOUGH LOW LEVEL CONVERGENCE TO SUPPORT SCATTERED MODERATE TO ISOLATED STRONG THUNDERSTORMS N OF 02N W OF 85W...MAINLY OFF THE COASTS OF WESTERN PANAMA AND COSTA RICA. THIS ACTIVITY IS ALSO BEING ENHANCED BY DIVERGENCE ALOFT SE OF A SHARP UPPER TROUGH REACHING FROM THE NE GULF OF MEXICO TO THE GULF OF TEHUANTEPEC. EARLIER ALTIMETER SATELLITE DATA INDICATED SEAS WERE GENERALLY 4 TO 6 FT...AND INDICATION THAT THE LONG PERIOD SW SWELL IN THE AREA OVER THE PAST SEVERAL DAYS HAS SUBSIDED. ANOTHER PUSH OF SW SWELL IS EXPECTED INTO THE AREA S OF 05N W OF 95W THROUGH LATE THU. LOOKING AHEAD...GLOBAL MODELS ARE STILL IN GENERAL AGREEMENT INDICATING THE DEVELOPMENT OF LOW PRES LATE IN THE WEEK INTO EARLY NEXT WEEK SOUTH OF TEHUANTEPEC...BUT DIFFER ON EXACT POSITION...TIMING AND STRENGTH. N OF 15N W OF 120W...WEAK 1013 MB LOW PRES NEAR 30N125W WILL LIFT IN OF THE AREA THROUGH EARLY THU AS RIDGING RECLAIMS ITS POSITIONED OVER THE AREA...CENTERED NEAR 25N135W. A COLD FRONT...ACCOMPANIED BY SCATTERED MODERATE THUNDERSTORMS...WILL MOVE INTO THE NW PORTION OF THE DISCUSSION AREA FRI THEN STALL FROM 32N130W TO 25N140W BY LATE FRI AND BECOME DIFFUSE SAT. NW SWELL WILL FOLLOW THE FRONT WITH SEAS 8 TO 9 FT FRI AND SAT...SPREADING AS FAR EAST AS 130W BY SUN. S OF 15N W OF 110W...NE TRADES ARE WEAK CURRENTLY...BUT WILL INCREASE SLIGHTLY TODAY AS HIGH PRES BUILDS TO THE NORTH. FROM TONIGHT THROUGH FRI...THE GENTLE TO MODERATE TRADES WITH SEAS 6 TO 7 FT IN MIXED NW AND SW SWELL WILL CONTINUE WITH OCCASIONAL PULSES OF CONVECTION FROM 05N TO 10N. BEYOND THAT...THE MAIN FORECAST ISSUE WILL BE THE DEVELOPMENT AND WESTWARD ADVANCEMENT OF THE AFOREMENTIONED LOW PRES CURRENTLY NEAR 10N112W. $$ CHRISTENSEN