AREA FORECAST DISCUSSION
FXUS66 KLOX 220001 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
505 PM PDT SUN MAY 21 2006

UPDATED AVIATION DISCUSSION

.SHORT TERM (TODAY-MON)...MAIN FOCUS OF OUR ATTENTION CONTINUES TO BE THE VERY LATE SEASON STORM POISED TO MOVE ONSHORE OVERNIGHT. THE MAIN UPPER LOW IS STILL 600 MILES TO OUR WEST AND HAS YET TO SHOW ANY EASTWARD PROGRESSION. FOR THIS REASON, THE FRONTAL BAND ALONG THE CENTRAL COAST HAS BEEN NEARLY STATIONARY, BRINGING MODERATE RAIN TO THE WESTERN HALF OF SLO COUNTY ALL DAY WHERE AMOUNTS ALREADY SO FAR RANGE FROM A HALF TO ONE INCH. ELSEWHERE, SCATTERED SHOWERS AVE BROUGHT MOSTLY A TENTH OR LESS.

18Z NAM CONTINUES TO SHOW THE FRONT FINALLY MOVING EAST THROUGH OUR AREA BETWEEN 00Z AND 12Z. THE COMBINATION OF PW`S AROUND 1.3 INCHES AND SOUTHERLY 850-700MB WINDS AROUND 50 KTS (BASED ON KVBX AND KVTX WIND PROFILERS AS WELL AS THE GOLETA PROFILER) WILL BRING PERIODS OF HEAVY RAIN TO SBA, VENTURA, AND LA COUNTIES TONIGHT. IN ADDITION, THE AIRMASS WILL BECOME INCREASINGLY UNSTABLE OVERNIGHT, ESPECIALLY FROM VENTURA COUNTY SOUTH AS THE LOW TRACKS OVERHEAD AND UPPER LEVEL DIVERGENCE PEAKS BETWEEN 06Z AND 12Z. GOOD DIRECTIONAL SHEAR IN THE LOW LAYERS AND THE CLOSE PROXIMITY OF THE UPPER LOW WILL DEFINITELY INCREASE THE CHANCES FOR WATERSPOUTS AND SMALL TORNADOES AND WILL NEED TO BE WATCHED VERY CLOSELY OVERNIGHT. WITH WINDS IN EXCESS OF 50 KTS BETWEEN 850 AND 500 MB IT`S QUITE POSSIBLE THESE STRONG WINDS COULD SURFACE IN A THUNDERSTORM DOWNDRAFT. WILL BE ISSUING A MARINE WEATHER STATEMENT SOON DETAILING THE CONVECTION CHANCES OVER OUR COASTAL WATERS TONIGHT.

WE`RE STICKING TO OUR RECENT FORECASTS FOR RAIN AS MODELS HAVE CHANGED LITTLE IN THE LAST 24 HOURS. GENERALLY 1-2 INCHES COAST AND 2-4 INCHES FOOTHILLS AND MOUNTAINS LOOKS REASONABLE. AMOUNTS WILL BE LOCALLY HIGHER WITH THUNDERSTORMS. RAINFALL RATES COULD EASILY EXCEED ESTABLISHED USGS THRESHOLDS WITH THIS EVENT AND THE FLASH FLOOD WATCH FOR THE BURN AREAS TONIGHT CERTAINLY LOOKS GOOD. THE BURN AREAS THAT WILL BE MOST AT RISK WILL BE THOSE THAT HAVE BURNED IN THE LAST 12 MONTHS. SEE THE LATEST FLASH FLOOD WATCH AND SPECIAL WEATHER STATEMENT FOR MORE DETAILS ON THIS STORM.

SNOW WILL NOT BE A BIG CONCERN WITH THIS EVENT. FREEZING LEVELS BASED ON AREAS SOUNDINGS AND EARLIER GOLETA PROFILER ARE RUNNING AROUND 10K FEET. THIS WILL LOWER TO BETWEEN 7000 AND 8000 FEET OVERNIGHT AND INTO MONDAY MORNING, BUT MOST OF THE SNOW ACCUMULATION WILL BE AT OR ABOVE BASE RESORT LEVELS.

THE UPPER LOW IS EXPECTED TO MOVE QUICKLY EAST THROUGH THE AREA ONCE IT FINALLY STARTS MOVING. AS A RESULT, STEADY RAIN AND THUNDERSTORMS SHOULD BE TAPERING OFF FROM WEST TO EAST LATER TONIGHT AND MONDAY MORNING, WITH JUST SCATTERED SHOWERS LINGERING INTO THE AFTERNOON.

.LONG TERM (TUE-SUN)...A NOTICEABLE IMPROVEMENT IN THE WEATHER IS EXPECTED THE REMAINDER OF THE WEEK, PARTICULARLY WED AND THU WHERE MOST COASTAL AREAS SHOULD BE IN THE UPPER 60S AND 70S AND VALLEYS SHOULD BE APPROACHING 90. AT SOME POINT WE EXPECT THE MARINE LAYER WILL MAKE A RETURN, BUT AFTER A STRONG SYSTEM LIKE THIS IT`S HARD TO PREDICT EXACTLY WHEN. A STRONG NW FLOW WILL DEVELOP LATE TUESDAY AND WEDNESDAY AND THIS COULD SPIN UP AN EDDY AS EARLY AS THURSDAY OR FRIDAY. IF THIS HAPPENS, LOOK FOR TEMPS TO COOL DOWN SEVERAL DEGREES AS WE APPROACH THE WEEKEND. OTHERWISE, A PRETTY NICE WEEK IN STORE.

&&

.AVIATION...RAIN WILL CONTINUE ACROSS AIRFIELDS NORTH OF POINT CONCEPTION...WITH IFR VIS AND MVFR/IFR CIG RESTRICTIONS UNDER THE HEAVIEST RAIN...WHICH SHOULD CONTINUE THROUGH LATE TONIGHT. WINDS WILL BE SOUTHERLY BUT SHOULD REMAIN LIGHT TO MODERATE...WITH CCASIONAL GUSTS TO AROUND 15 KT.

SOUTH OF POINT CONCEPTION...PREFRONTAL RAINBANDS CONTINUE TO PRODUCE LIGHT RAIN WITH OFF AND ON AGAIN MVFR CIGS...EXCEPT FOR LA COUNTY AIRFIELDS WHERE THE MVFR CIGS ARE HERE TO STAY. MAIN RAINBAND WILL CONTINUE TO WORK ITS WAY DOWN THE COAST...REACHING KSBA AROUND 01Z AND KLAX JUST BEFORE MIDNIGHT.

KLAX WILL SEE EASTERLY WINDS THROUGH MONDAY MORNING. SPEEDS WILL HOVER BETWEEN 8 AND 12 KT UNTIL THE MAIN RAINBAND COMES NEAR...THEN WINDS SHOULD REMAIN EAST-SOUTHEAST ABOVE 10 KT THROUGH ABOUT 12Z BEFORE RELAXING. CIGS WILL LOWER TO IFR ONCE MAIN RAINBAND COMES.

.LOX WATCHES/WARNINGS/ADVISORIES...
FLOOD WATCH (SEE LAXFFALOX).
SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

&&

PUBLIC...WOFFORD
AVIATION...KITTELL