AREA FORECAST DISCUSSION

 
 FXUS66 KLOX 121001
 AFDLOX
 
 SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
 300 AM PDT MON MAY 12 2008
 
 .SHORT TERM (TODAY THROUGH WEDNESDAY)...ANOTHER DAY...ANOTHER ROUND 
 OF MARINE LAYER. LATEST SATELLITE SHOWS STRATUS/FOG COVERING ALL 
 COAST/VALLEY ZONES...WITH SOME STRATUS/FOG PUSHING INTO/THROUGH THE 
 COASTAL SLOPES. EARLIER CGR REPORT AT CHANNEL ISLANDS INDICATED 
 DRIZZLE. SO...HAVE INCLUDED PATCHY DRIZZLE FOR AREAS WEST OF THE
 MOUNTAINS FROM SOUTHERN SBA COUNTY THROUGH LAX COUNTY. WITH A 
 FORECASTED LAX-DAG GRADIENT OVER 10 MB...WILL EXPECT SLOW...IF ANY 
 CLEARING OF THE MARINE LAYER WEST OF THE MOUNTAINS THIS AFTERNOON. 
 WITH THE ONSHORE GRADIENTS...GUSTY WESTERLY WINDS WILL DEVELOP 
 ACROSS THE ANTELOPE VALLEY. GIVEN THE CURRENT OBS FROM ZONE 
 59...WILL ISSUED WIND ADVISORY WITH THE MORNING ZONES...AND WILL 
 INCLUDE BLOWING DUST/SAND FOR THE ANTELOPE VALLEY. AS FOR TEMPS 
 TODAY...WILL EXPECT ANOTHER COOL DAY ACROSS THE AREA...ESPECIALLY 
 WEST OF THE MOUNTAINS.
 
 FOR TONIGHT/TUESDAY...00Z WRF/GFS IN GOOD AGREEMENT...DROPPING AN
 UPPER LOW ACROSS THE GREAT BASIN. SOME NORTHERLY FLOW ASSOCIATED
 WITH THIS FEATURE WILL HAVE SOME IMPACT UPON THE MARINE LAYER...
 WITH A SLIGHTLY MORE SHALLOW AND LESS EXTENSIVE MARINE LAYER. SOME
 GUSTY NORTHERLY WINDS CAN BE EXPECTED ACROSS THE MOUNTAINS...BUT
 NO CONCERNS FOR ADVISORY LEVELS AT THIS TIME. WITH THIS PATTERN...
 WILL HAVE MUCH WEAKER ONSHORE GRADIENTS...SO THE MARINE LAYER WILL
 CLEAR TO MOSTLY SUNNY SKIES TUESDAY AFTERNOON. AS FOR TEMPS...WILL
 EXPECT NOTICEABLE WARMING FOR ALL AREAS...GIVEN WEAKER ONSHORE 
 GRADIENTS AND LESS MARINE LAYER INFLUENCE.
 
 FOR TUESDAY NIGHT/WEDNESDAY...UPPER RIDGE OVER THE EASTERN PACIFIC
 EDGES CLOSER TO THE CALIFORNIA COAST. NEAR THE SURFACE...MORNING
 GRADIENTS TURN WEAKLY OFFSHORE. AS THIS PATTERN DEVELOPS...THE 
 MARINE LAYER IS EXPECTED TO BE SQUASHED. THE COMBO OF HIGHER 
 THICKNESSES... WARMER BOUNDARY LAYER TEMPS AND WEAK OFFSHORE 
 GRADIENTS WILL ALLOW FOR EVEN MORE WARMING WEDNESDAY AFTERNOON
 WITH SOME VALLEY AREAS CLIMBING INTO THE LOWER 90S.
 
 .LONG TERM (WEDNESDAY NIGHT THROUGH SUNDAY)...HEAT SHOULD PEAK ON
 THURSDAY/FRIDAY AS UPPER RIDGE PEAKS IN STRENGTH OVER THE WEST
 COAST AND OFFSHORE GRADIENTS INCREASE. ONCE AGAIN...LOCAL TEMP
 STUDY DATA INDICATES TEMPS SHOULD BE AROUND RECORD LEVELS WITH 
 VALLEY AREAS IN THE UPPER 90S TO LOWER 100S AND DOWNTOWN LA IN
 THE 90S. FORTUNATELY...UPPER SUPPORT DOES NOT LOOK GREAT...SO 
 NO WIDESPREAD ADVISORY LEVEL WINDS ARE EXPECTED AT THIS TIME.
 
 FOR SATURDAY/SUNDAY...UPPER RIDGE WEAKENS AND WEAK ONSHORE FLOW
 REESTABLISHES ACROSS THE AREA. SO...WILL EXPECT NOTICEABLE COOLING
 ON SATURDAY AND SUNDAY...WITH SOME PATCHY MARINE LAYER POSSIBLY
 RETURNING TO THE COASTAL AREAS SUNDAY MORNING. 
 
 &&
 
 .AVIATION...12/1130Z.
 
 WILL BE UPDATED SHORTLY.
 
 &&
 
 .LOX WATCHES/WARNINGS/ADVISORIES...
 WIND ADVISORY (SEE LAXNPWLOX).
 GALE WARNING (SEE LAXCWFLOX).
 SMALL CRAFT ADVISORY (SEE LAXCWFLOX).
 SPECIAL WEATHER STATEMENT (SEE LAXSPSLOX).
 
 &&
 
 

 
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 AVIATION...BRUNO
 
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