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000 FXUS66 KLOX 191110 AAA AFDLOX SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 409 AM PDT FRI SEP 19 2008 UPDATED AVIATION SECTION .SHORT TERM...SKIES WERE CLEAR ACROSS THE ENTIRE AREA THIS MORNING... AND ARE EXPECTED TO REMAIN SO TODAY. UPPER LOW OFF THE COAST OF NRN CA WILL LIFT NEWD AND OPEN UP LATER TODAY AND TONIGHT. THE SRN END OF THE WEAKENING SFC BOUNDARY ASSOCD WITH THIS SYSTEM WILL MOVE THROUGH THE FCST AREA LATER TODAY AND TONIGHT. SOME COOLING AT 850 MB BEHIND THIS BOUNDARY MAY BRING SLIGHT COOLING TO INTERIOR SECTIONS N OF PT CONCEPTION TODAY. WITH LITTLE CHANGE IN 850/950 MB ELSEWHERE...AND ONLY A SLIGHT INCREASE IN ONSHORE GRADS...EXPECT MOSTLY MINOR CHANGES IN MAX TEMPS TODAY COMPARED TO THOSE REACHED THU. LOW LVL NLY GRADS ARE FCST TO INCREASE ACROSS THE CENTRAL COAST LATER TODAY AND TONIGHT...AND THERE WILL SOME DECENT SUBSIDENCE AND A PERIOD OF FAIRLY NW TO NLY WINDS OF UP TO 30 KT ACROSS SRN SBA COUNTY TONIGHT. EXPECT SOME GUSTY WINDS ON THE CENTRAL COAST THIS AFTERNOON...AND THRU AND BELOW PASSES AND CANYONS OF SRN SBA COUNTY TONIGHT. WINDS COULD APCH ADVISORY LEVELS IN THE SANTA YNEZ MTNS AND BELOW ADJACENT PASSES AND CANYONS OF SRN SBA COUNTY TONIGHT. THE WRF IS SHOWS AN EDDY CRCLN TRYING TO DEVELOP LATE TONIGHT...WITH SOME INCREASE IN LOW LVL MOISTURE ACROSS AT LEAST COAST SECTIONS OF L.A. AND POSSIBLY VTU COUNTIES. STILL...DO NOT EXPECT WDSPRD STRATUS TONIGHT/SAT MORNING...AND WHAT OCCURS WILL LIKELY BE CONFINED TO THE L.A. COUNTY COAST. WHILE THICKNESS VALUES CHANGE LITTLE...INCREASING ONSHORE GRADS AND SOME COOLING AT 850 AND 950 MB SHOULD KNOCK A FEW DEGREES OFF MAX TEMPS IN MOST AREAS ON SAT...WITH TEMPS GENERALLY SLIGHTLY BELOW NORMAL ACROSS THE FCST AREA. THERE COULD AGAIN BE SOME LOCALLY GUSTY WINDS THRU AND BELOW PASSES AND CANYONS OF SRN SBA COUNTY SAT NIGHT...BUT THEY ARE NOT EXPECTED TO BE AS STRONG AS ANY UPPER SUPPORT FADES. GUSTY WINDS MAY ALSO AFFECT THE I5 CORRIDOR SAT NIGHT. BROAD CYCLONIC FLOW ALF WILL CONT ACROSS THE AREA SAT NIGHT AND SUNDAY...WITH MINOR CHANGES IN HEIGHTS/THICKNESSES. THERE WILL PROBABLY BE SOMEWHAT MORE IN THE WAY OF NIGHT THRU MORNING LOW CLOUDS AND FOG IN CSTL SXNS OF L.A. AND VTU COUNTIES AND ON THE CENTRAL COAST...AND SOME CLOUDS COULD SPREAD INTO THE SAN GABRIEL VALLEY. THERE COULD BE SOME SLIGHT COOLING ON SUNDAY...ESPECIALLY IN CSTL AND VLY AREAS AS 950 MB TEMPS DROP A BIT MORE. .LONG TERM...THERE WILL BE LITTLE CHANGE IN THE UPPER PATTERN SUN NIGHT AND MONDAY. THE WRF SUGGESTS A MORE WIDESPREAD AND INVASIVE STRATUS FIELD SUN NIGHT/MON MORNING...WITH CLOUDS PROBABLY SPREADING INTO MOST VLY AREAS. WITH THE INCREASED CLOUD COVER...THERE WILL LIKELY BE ADDITIONAL COOLING IN CSTL AND VALLEY AREAS MON. HEIGHTS BEGIN TO RISE ON TUE AS RIDGING AMPLIFIES OFF THE W CST. EXPECT SOME WARMING IN MOST AREAS ON TUE...AND THE MARINE LAYER SHOULD BECOME MORE SHALLOW. AN UPPER HIGH OFF THE CST IS FCST TO MOVE RIGHT OVER THE AREA WED AND LINGER THRU THU. AT THE SAME TIME...LOW LVL ONSHORE GRADS WILL TURN WEAKLY OFFSHORE OR AT LEAST NEUTRAL WED MORNING AND THU MORNING. IF THIS OCCURS...EXPECT A SHARP REDUCTION IN THE STRATUS...WITH CLDS LIKELY CONFINED TO THE CST DURG THE LATE NIGHT THRU MORNING HOURS WED AND THU. SIGNIFICANT WARMING IS EXPECTED WED...ESPECIALLY IN THE VALLEYS AND ACROSS INTERIOR SXNS OF THE CSTL PLAIN...WITH SLIGHT ADDITIONAL WARMING THU AS THICKNESSES EDGE UPWARD. && .AVIATION...19/1109Z. VFR CONDITIONS ARE EXPECTED AT ALL TERMINALS THROUGHOUT THE PERIOD WITH LOCAL MVFR VISIBILITIES AT COASTAL TERMINALS THROUGH 15Z. OCCASIONAL LOW-LEVEL WIND SHEAR AND TURBULENCE ISSUES ARE POSSIBLE TONIGHT BETWEEN 23Z THIS AFTERNOON AND 10Z TONIGHT AT KSBA. KLAX...VFR CONDITIONS ARE EXPECTED THROUGHOUT THE PERIOD. KBUR...VFR CONDITIONS ARE EXPECTED THROUGHOUT THE PERIOD. && .LOX WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY (SEE LAXMWWLOX). && $$ PUBLIC...BRUNO AVIATION...HALL WWW.WEATHER.GOV/LOSANGELES