000 AXPZ20 KNHC 110930 TWDEP TROPICAL WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 1005 UTC FRI JUN 11 2010 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 0730 UTC. ...TROPICAL WAVES... TROPICAL WAVE ALONG 82W N OF 04N MOVING W 15 KT. THERE IS NO SIGNIFICANT CONVECTION CURRENTLY NOTED NEAR THIS WAVE. 20-30 KT OF EASTERLY SHEAR ALOFT IS INHIBITING THE DEVELOPMENT OF DEEP CONVECTION NEAR THE WAVE. TROPICAL WAVE ALONG 88W N OF 05N MOVING W-NW 15 KT. SCATTERED MODERATE CONVECTION LIES WITHIN 150 NM W OF THE WAVE N OF 12N INTO EL SALVADOR...WESTERN HONDURAS...AND SOUTHERN GUATEMALA. THIS WAVE IS EXPECTED TO REMAIN UNDER BROADLY DIFFLUENT FLOW ALOFT OVER THE NEXT DAY OR TWO. THIS MAY HELP ENHANCE CONVECTION NEAR THE WAVE. THE 0352 UTC ASCAT PASS INDICATED S WINDS AROUND 20 KT ON THE W SIDE OF THE WAVE AXIS. TROPICAL WAVE FROM 15N102W TO 07N105W MOVING W 10-15 KT. THERE IS NO SIGNIFICANT CONVECTION NOTED IN THE VICINITY OF THIS WAVE AT THE MOMENT. SATELLITE TOTAL PRECIPITABLE WATER IMAGERY INDICATES AN EROSION OF DEEP LAYER MOSITURE NEAR THIS WAVE. THE 0354 UTC ASCAT PASS WAS USED TO PLACE THE WAVE. ...ITCZ... THE INTERTROPICAL CONVERGENCE ZONE AXIS WAS ANALYZED FROM 09N85W TO 09N92W TO 11N96W TO 008N130W TO 05N140W. SCATTERED MODERATE CONVECTION WAS WITHIN 240 NM S OF THE ITCZ AXIS BETWEEN 88W AND 98W AND WITHIN 90 NM S AND 45 NM N OF THE ITCZ AXIS BETWEEN 108W AND 119W. A TROUGH IS EMBEDDED IN THE ITCZ FROM 11N130W TO 05N133Q. IT HAS SCATTERED MODERATE CONVECTION WITHIN 180 NM W AND 120 NM E OF THE TROUGH FROM 05N TO 09N. ...DISCUSSION... AN UPPER TROUGH EXTENDS FROM THE U.S GREAT BASIN SOUTHWESTWARD OFF THE CALIFORNIA COAST NEAR POINT CONCEPTION TO 30N122W THEN TO AN UPPER LOW NEAR 21N140W AND THEN SW TO ANOTHER LOW NEAR 13N147W. 30-40 KT SOUTHERLY FLOW ALOFT OVER W WATERS ON THE LEADING EDGE OF THIS TROUGH IS PICKING UP MID TO UPPER LEVEL MOSITURE FROM CONVECTIVE BLOW OFF FROM THE ITCZ W OF THE AREA AND TRANSPORTING IT NE INTO W WATERS IN THE FORM OF CIRRUS. OTHERWISE...STRATOCUMULUS DOMINATES THE SKIES N OF 15N W OF 110W. TO THE N OF THIS UPPER TROUGH LIES AN ANTICYCLONE NEAR 32N139W. DEEP LAYER RIDGING CAN BE FOUND DOWN TO THE SURFACE WHERE A 1035 MB HIGH LIES NEAR 37N135W. STRONG SURFACE RIDGING EXTENDS SE FROM THE LOW TO NEAR 15N115W. THE PRES GRADIENT BETWEEN THIS RIDGING AND STRONG SURFACE TROUGHING OVER THE SW U.S. HAS INDUCED NW TO N WINDS TO 25 KT ALONG THE NORTHERN BAJA AND W TO NEAR 128W...WITH NW SWELL TO 12 FT IN THIS AREA ORIGINATING FROM THE GALE FORCE WINDS JUST N OF THE AREA OFF THE CALIFORNIA COAST. THE STRONG SURFACE RIDGING HAS ALSO INDUCED EASTERLY TRADE WINDS TO 25 KT OVER W WATERS N OF THE ITCZ TO 27N ACCORDING TO THE 0536-0540 UTC ASCAT PASS. A DEEP LAYERED TROUGH APPROACHING THE HIGH CENTER FROM THE W WILL WEAKEN THE RIDGING OVER FORECAST WATERS OVER THE NEXT TWO DAYS AND THIS WILL REDUCE THE AREA OF WINDS GREATER THAN 20 KT OFF THE BAJA COAST AND THE TRADE WINDS CONSIDERABLY THROUGH SAT. IN ADDITION...THE 20 KT SOUTHERLY WINDS IN THE GULF OF CALIFORNIA OBSERVED BY BATFR53 AND THE 0358 UTC ASCAT PASS N OF 25N WILL DIMINISH BY SAT AFTERNOON. IN THE TROPICS...AN UPPER RIDGE EXTENDS FROM 10N140W TO AN ANTICYCLONE OVER MEXICO NEAR 21N99W. AS THE DEEP LAYER TROUGH TO THE N OVER THE U.S. SHIFTS EAST...IT WILL SEVERE THE RIDGE...CAUSING IT TO SHED AN ANTICYCLONE OVER W WATERS NEAR 17N130W BY SAT MORNING. AN UPPER LOW CURRENTLY LIES S OF THE RIDGE AXIS NEAR 03N129W. DIFFLUENT FLOW ALOFT BETWEEN THE NW QUADRANT OF THIS LOW AND THE RIDGE HAS HELPED THE CAUSE FOR CONVECTION NEAR THE SURFACE TROUGH EMBEDDED IN THE ITCZ FROM 11N130W TO 05N133W. ASIDE FROM THE AFOREMENTIONED TROPICAL WAVES...THE ONLY OTHER FEATURE OF NOTED IN THE TROPICS IS THE SW SWELL CURRENTLY INCHING INTO SW WATERS AND EXPECTED TO RAISE SIGNIFICANT WAVE HEIGHTS TO 11 FT OVER S CENTRAL AND SE WATERS BY SAT. THE LEADING EDGE OF THIS SWELL TRAIN IS EXPECTED TO REACH MUCH OF THE COASTLINE OVER FORECAST WATERS S OF SOUTHERN BAJA CALIFORNIA BY SUNSET SAT...WITH PERIODS AROUND 18 SECONDS AND SEAS TO 7 FT. $$ SCHAUER