000 AXPZ20 KNHC 031557 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 1605 UTC WED AUG 03 2011 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 1500 UTC. ...SPECIAL FEATURES... HURRICANE EUGENE AT 15.7N 114.1W AT 03/1500Z UTC MOVING W-NW OR 290 DEGREES AT 12 KT WITH CENTRAL PRES 949 MB. MAXIMUM SUSTAINED WINDS ARE 110 KT WITH GUSTS TO 135 KT. EUGENE HAS MAINTAINED A LARGE BUT RAGGED EYE FEATURE OVERNIGHT. NUMEROUS STRONG CONVECTION OCCURRING WITHIN 90 NM NE AND 140 NM SW SEMICIRCLE OF EUGENE WITH SCATTERED MODERATE TO STRONG CONVECTION ELSEWHERE WITHIN 220 NM TO THE S. EUGENE REMAINS UNDER FAVORABLE UPPER LEVEL CONDITIONS BUT HAS BEGUN TO MOVE OVER SLIGHTLY COOLER WATER TEMPERATES. THUS EUGENE IS NEAR OR HAS LIKELY REACHED ITS PEAK INTENSITY. EUGENE IS FORECAST TO CONTINUE TO MOVE W-NW OVER THE NEXT TWO DAYS...AND OVER GRADUALLY COOLER WATER...LEADING TO A SLOW WEAKENING TREND...BUT IS EXPECTED TO REMAIN A HURRICANE THROUGH AT LEAST EARLY FRI MORNING. SEE LATEST NHC PUBLIC ADVISORY UNDER AWIPS/WMO HEADERS TCPEP5/WTPZ35 KNHC AND FULL FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS TCMEP5/WTPZ25 FOR MORE DETAILS. A 1006 MB LOW PRES SYSTEM SW OF THE GULF OF TEHAUNTEPEC NEAR 14N98W REMAINS EMBEDDED WITHIN A BROAD AREA OF VERY HIGH MOISTURE ALONG COASTAL MEXICO. SCATTERED MODERATE TO STRONG CONVECTION WAS OCCURRING N OF 13N TO THE MEXICAN COAST BETWEEN 98W AND 105W. THIS ACTIVE WEATHER AND ASSOCIATED MOISTURE WILL SHIFT W-NW OVER THE NEXT FEW DAYS AND CONTINUE TO AFFECT COASTAL MEXICO AND THE ADJACENT COASTAL WATERS...AND BEGIN TO SPREAD TO S OF THE MOUTH OF THE GULF OF CALIFORNIA ON FRIDAY. ENVIRONMENTAL CONDITIONS APPEAR FAVORABLE FOR THE DEVELOPMENT OF THIS SYSTEM INTO A TROPICAL CYCLONE OVER THE NEXT DAY OR TWO AS THE SYSTEM TRACKS W-NW. ...ITCZ/MONSOON TROUGH... MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 1006 MB LOW PRES NEAR 14N98W THEN CONTINUES FROM 12N118W TO 10N126W. THE ITCZ AXIS EXTENDS FROM 10N126W TO 07N140W. SCATTERED MODERATE TO ISOLATED STRONG FROM 03N TO 07N E OF 80W TO THE COAST OF COLOMBIA. SIMILAR CONVECTION IS FROM 06N TO 09N BETWEEN 80W AND 87W. ...DISCUSSION... THE EPAC SUBTROPICAL HIGH CONTINUES TO BE WEAKENED AND DISPLACED WESTWARD BY MEAN DEEP LAYERED TROUGHING JUST OFF THE W COAST OF THE UNITED STATES. AS A RESULT...TYPICAL FRESH TRADE WINDS ACROSS THE AREA ARE LIMITED TO WATERS W OF 130W. OVERNIGHT SCATTEROMETER PASSES SHOWED WINDS TO 20 KT FROM 10N TO 22N WITH THE 0530 UTC JASON 1 PASS SHOWING SEAS AS HIGH AS 9 FT IN SW SWELL IN THE S PORTION OF THAT AREA NEAR THE ITCZ. A WEAK MIDDLE TO UPPER LEVEL TROUGH ENTERS THE AREA NEAR 30N130W AND MEANDERS SW TO NEAR 17143W. E OF THIS TROUGH...A MEAN UPPER RIDGE PERSISTS ACROSS THE S CENTRAL U.S. AND THE NRN GULF OF MEXICO...EXTENDING SW TO AN ANTICYCLONE OVER CENTRAL BAJA CALIFORNIA NEAR 26N113W...WITH RIDGING CONTINUING SW TO NEAR 16N125W. INVERTED MID TO UPPER TROUGHING FROM 23N125W TO THE ITCZ ALONG 135W SEPARATES THIS RIDGE FROM A WEAKENING UPPER ANTICYCLONE NEAR 21N134W. THE LARGE RIDGE AXIS PENETRATES INTO THE MID LEVELS AND WILL REMAIN RELATIVELY STATIONARY OVER THE NEXT FEW DAYS...AND MAINTAIN A GENERAL W TO W-NW STEERING FLOW ACROSS MUCH OF THE TROPICAL EPAC E OF 120W...AND GUIDE BOTH HURRICANE EUGENE...AND THE LOW PRES SYSTEM TO ITS E...TO MOVE W-NW. SCATTERED TO NUMEROUS MODERATE TO STRONG CONVECTION LIES N OF 06N E OF 84W ACROSS THE GULF OF PANAMA AND OVER PORTIONS OF PANAMA AND INTO NW COLOMBIAN. THIS CONVECTION IS OCCURRING IN THE MOISTURE RICH AIR JUST S OF THE MONSOON TROUGH AND UNDER A REGION OF WEAK ELY WINDS ALOFT. CONVECTION IS EXPECTED TO REMAIN ACTIVE THERE FOR THE NEXT 24-48 HOURS AS ADDITIONAL LOW LEVEL MOISTURE MOVES FROM E PORTIONS OF COLOMBIA AND THE ADJACENT CARIBBEAN...AND CONVERGES S OF THE MONSOON TROUGH. AN OVERNIGHT 0446 UTC ASCAT PASS CAPTURED FRESH TO STRONG SW WINDS FEEDING INTO EUGENE FROM N OF 04N BETWEEN 107W AND 122W. OVERNIGHT SCATTEROMETER PASSES ALSO SHOWED LIGHT TO MODERATE SW TO WLY FLOW OCCURRING S OF THE MONSOON TROUGH FROM 100W E INTO COLOMBIA. EUGENE MANAGED TO SLIP BETWEEN THE JASON 1 PASS FROM 0340 UTC AND THE JASON 2 PASS FROM 0430 UTC...WITH 10 FT SEAS REPORTED WITHIN 570 NM SE QUADRANT OF EUGENE. THE 12 FT SEA RADII WERE EXPANDED IN THE E SEMICIRLCE BASED ON THIS PASS AND THE WAVE MODEL FORECAST GUIDANCE. LONG PERIOD CROSS-EQUATORIAL SW SWELL HAS BROUGHT SEAS ABOVE 8 FT TO S CENTRAL WATERS S OF 05N AND W OF 96W...AS CONFIRMED BY THE AFOREMENTIONED JASON1 PASS. A NEW PULSE OF 16-18 SECOND PERIOD SW SWELL WILL MOVE INTO THE AREA TONIGHT AND KEEP COMBINED SEAS IN THE 8-10 FT RANGE THERE THROUGH THE FORECAST PERIOD. $$ STRIPLING