000 AXPZ20 KNHC 080330 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT AUG 08 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 0345 UTC. ...SPECIAL FEATURES... HURRICANE FELICIA IS NEAR 18.8N 138.0W AT 08/0300 UTC WITH MAXIMUM SUSTAINED WINDS 90 KT WITH GUSTS TO 110 KT. FELICIA IS MOVING WNW OR 295 DEG AT 12 KT WITH AN ESTIMATED MINIMUM CENTRAL PRESSURE OF 970 MB. FELICIA HAS INTENSIFIED SLIGHTLY WITH LITTLE CHANGE IN THE SIZE OF THE CENTRAL DENSE OVERCAST. THE EYE MAINTAINS A RADIUS OF 15 NM. NUMEROUS MODERATE TO STRONG CONVECTION IS WITHIN 90 NM OF FELICIA. FELICIA IS FORECAST TO SLOWLY WEAKEN DURING THE NEXT COUPLE OF DAYS AS THE HURRICANE MOVES OVER COOLER WATERS AND BEGINS TO ENCOUNTER INCREASING WIND SHEAR. NONE THE LESS FELICIA IS FORECAST TO MOVE INTO THE CENTRAL PACIFIC HURRICANE CENTER AREA OF RESPONSIBILITY AS A HURRICANE IN LESS THAN 24 HOURS. SEE THE LATEST NHC FORECAST/ ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC FOR MORE DETAILS. THE REMNANT LOW OF TROPICAL DEPRESSION ENRIQUE IS NEAR 25N130W AT 08/0000 UTC WITH MAXIMUM SUSTAINED WINDS 20-25. THE LOW IS NEARLY STATIONARY WITH AN ESTIMATED MINIMUM CENTRAL PRESSURE OF 1009 MB. THE LOW HAS LOST ALL DEEP CONVECTION AND IS ESSENTIALLY A SWIRL OF LOW AND MID LEVEL CLOUDS WITH EMBEDDED SHOWER ACTIVITY. ...TROPICAL WAVES... A TROPICAL WAVE IS OVER CENTRAL AMERICA N OF 07N ALONG 92W MOVING W AT 15 KT OVER THE PAST 24 HOURS. AMPLE MOISTURE WAS NOTED BEHIND THIS WAVE ACROSS THE SRN CARIBBEAN AND NRN S AMERICA. THIS WAVE HAS BEEN TILTED NW TO SE AND STRETCHED SIGNIFICANTLY AS IT MOVED ACROSS THE TROPICAL ATLC AND CARIBBEAN...AND IS NOT CURRENTLY INDUCING MUCH IN THE WAY OF CONVECTION IN THE EASTERN PACIFIC. A TROPICAL WAVE IS ESTIMATED ALONG 123W FROM 04N TO 15N MOVING W NEAR 10 KT OVER THE PAST 24 HOURS. SATELLITE IMAGERY SHOWED A LOW TO MID LEVEL CYCLONIC CIRCULATION ASSOCIATED WITH THIS WAVE...AND WAS PART OF A BROAD ZONE OF LOW LEVEL CYCLONIC TURNING ACROSS THIS AREA. SCATTERED MODERATE CONVECTION WAS OCCURRING WITHIN 120 NM EITHER SIDE OF THE WAVE AXIS. MORE WIDESPREAD CONVECTION WAS OCCURRING TO THE EAST OF THE WAVE IN ASSOCIATION WITH A SURFACE TROUGH ALONG 115W FROM 07N TO 14N. ...ITCZ... THE AXIS IS FROM 08N77W TO 09N92W TO 08N100W TO 11N120W TO 10N130W 14N135W 12N140W. SCATTERED MODERATE CONVECTION IS FROM 05N TO 08N BETWEEN 82W AND 94W...FROM 07N TO 12N BETWEEN 98W AND 101W...AND FROM 10N TO 13N BETWEEN 130W AND 133W. ...DISCUSSION... A LARGE AND DEEP LAYERED TROUGH ACROSS THE WRN U.S. EXTENDS S INTO SRN CALIFORNIA...WITH A S/W SWINGING THROUGH THE BASE OF THE TROUGH ALONG 125W AND A TRAILING S/W NEAR 32N131W. ELONGATED TROUGHING EXTENDS FROM THIS FEATURE TO A BROAD UPPER LOW N OF THE HAWAIIAN ISLANDS. S OF THIS ELONGATED CONNECTING TROUGH... S TO SWLY FLOW...AND AN ANTICYCLONE TO THE NE OF HURRICANE FELICIA HAVE AIDED IN MAINTENANCE OF THE HURRICANES INTENSITY... WHILE THE STRONG SWLY UPPER FLOW HAS SHEARED ENRIQUE. MODEST UPPER EASTERLIES AND DIFFLUENT FLOW ALOFT ARE HELPING TO MAINTAIN AN ACTIVE ITCZ THROUGHOUT THE BASIN W OF 90W. REMNANT LOW OF ENRIQUE HAS BEEN CAPTURED BY A MID LEVEL EXTENSION OF THE WRN U.S. TROUGH...WHILE FELICIA HAS MOVED WITH A MORE WWD COMPONENT WITH THE TWO SYSTEMS SEPARATING. A MID TO UPPER LOW NEAR 20N120W IS MOVING W AND PRODUCING VENTILATION TO ITS E...AIDING IN MAINTAINING DEEP CONVECTION ASSOCIATED WITH THE TROPICAL WAVE ALONG 121W AND THE SURFACE TROUGH IN ITS WAKE. A WIND MAX SLICING ACROSS NRN MEXICO COUPLED WITH DIFFLUENT FLOW TO THE S OF AN ANTICYCLONE NEAR 27N108W HAS MAINTAINED AN AREA OF DEEP CONVECTION ALONG THE MEXICAN COAST AND THE ADJACENT SOUTHERN PORTIONS OF THE GULF OF CALIFORNIA ALL DAY. ADDITIONAL CONVECTION WAS FLARING UP IN THE VICINITY OF CABO CORRIENTES. A PERSISTENT...BROAD...AND DEEP LAYER RIDGE OVER THE SOUTH CENTRAL UNITED STATES AND NORTHERN MEXICO IS ASSOCIATED WITH A SURFACE RIDGE OVER MEXICO THAT BECOMES MOST PRONOUNCED AT NIGHT. THE SURFACE PRESSURE GRADIENT TO THE S OF THIS SURFACE RIDGE... COMBINED WITH VARIATIONS IN TOPOGRAPHY WITHIN THE CHIVELA PASS CONTINUE TO SUPPORT A SMALL PLUME OF N TO NE WINDS OF 20 KT IN THE GULF OF TEHUANTEPEC AS INDICATED BY A 1204 UTC HIGH RESOLUTION QUIKSCAT PASS. DURING THE NEXT COUPLE DAYS...THESE WINDS WILL LIKELY DIMINISH...AS THE DEEP LAYER RIDGE SLIDES EASTWARD. THE CLIMATOLOGICAL BROAD SURFACE RIDGE ACROSS THE E CENTRAL PACIFIC IS COMBINING WITH A SURFACE TROUGH OVER FAR NW MEXICO AND THE GULF OF CALIFORNIA TO PRODUCE A MODEST PRESSURE GRADIENT OFF THE COAST OF BAJA CALIFORNIA...WITH NW WINDS OF 20 TO 25 KT EXPECTED TO CONTINUE WITHIN 120 NM W OF THE COAST OF BAJA CALIFORNIA FOR THE NEXT 24 HOURS. IN THE GULF OF PAPAGAYO...NE TO E WINDS TO 20 KT WILL OCCUR DURING THE NEXT 24 HOURS WITH FRESH TO STRONG TRADE WINDS PERSISTING OVER THE CENTRAL AND SW CARIBBEAN. PULSES OF SRN HEMISPHERE SW SWELL CONTINUE TO INVADE THE TROPICAL EPAC AND ARE MAINTAINING SEAS TO 8 FT S OF THE EQUATOR...AND GENERALLY 5 TO 7 FT FROM S OF THE BAJA TO PANAMA. A NEW PULSE OF THIS SW SWELL IS CURRENTLY REACHING CENTRAL AMERICA AND WILL INCREASE ACROSS THE REGION DURING THE NEXT 48 HOURS. $$ FORMOSA