871  
FXUS66 KLOX 260326  
AFDLOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA  
826 PM PDT THU AUG 25 2016  
   
SYNOPSIS
 
 
MARINE LAYER CLOUDS WILL PERSIST ALONG THE COAST AND SOME VALLEYS  
NIGHT AND MORNING HOURS THROUGH LATE NEXT WEEK, OTHERWISE MOSTLY  
CLEAR SKIES WILL PREVAIL. COOLER TEMPERATURES CAN BE EXPECTED INTO  
THE WEEKEND AS A WEAK UPPER LEVEL TROUGH OF LOW PRESSURE MOVES IN.  
HIGH PRESSURE WILL BUILD INTO THE AREA SUNDAY AND INTO EARLY NEXT  
WEEK FOR ABOVE NORMAL TEMPERATURES IN MANY AREAS, FOLLOWED BY A  
COOLING TREND THRU MID WEEK AS LOW PRESSURE MOVES BACK IN.  

 
   
SHORT TERM
 
(THU-SUN)  
 
UPPER LEVEL TROUGH WILL CONTINUE TO DEEPEN ACROSS CALIFORNIA  
DURING NEXT 24 HOURS. ALREADY SAW A COOLING TREND WITH STRONGER  
ONSHORE FLOW TODAY. HEIGHTS/THICKNESSES WILL CONTINUE TO FALL ON  
FRIDAY,LEADING TO ADDITIONAL CONTINUE FOR MANY AREAS ON FRIDAY.  
MOST INLAND AREAS WILL ONLY BE IN THE 80S ON FRIDAY, WITH THE  
EXCEPTION OF THE ANTELOPE VALLEY CLIMBING INTO THE LOWER 90S. 00Z  
VANDENBERG SOUNDING SHOWING MARINE LAYER DEPTH AROUND 1700 FEET.  
ACARS SOUNDING SHOWING MARINE LAYER DEPTH AROUND 1600 FEET ACROSS  
THE LA BASIN, BUT SHOULD DEEPEN TO AROUND 2000 FEET BY FRIDAY  
MORNING.  
 
SATELLITE IMAGERY ALREADY SHOWING LOW CLOUDS DEVELOPING ACROSS  
THE LA COAST AND CENTRAL COAST THIS EVENING. WITH THE DEEPENING  
MARINE LAYER AND STRONGER ONSHORE FLOW, EXPECTING LOW CLOUDS  
TO FILL INTO MANY VALLEY LOCATIONS OVERNIGHT INTO FRIDAY MORNING.  
ALSO EXPECTING SOME LOW CLOUDS TO LINGER ACROSS SOME IMMEDIATE  
COASTAL AREAS ON FRIDAY AFTERNOON. THE INCREASED MARINE LAYER  
INFLUENCE ON FRIDAY IS EXPECTED TO BETTER HUMIDITY RECOVERIES AND  
COOLER TEMPERATURES TO BOTH THE CHIMNEY AND REY WILDFIRES TONIGHT  
INTO FRIDAY, HOWEVER THERE WILL BE THE POTENTIAL FOR GUSTY ONSHORE  
WINDS AT BOTH FIRE LOCATIONS DURING THE AFTERNOON HOURS.  
 
***FROM PREVIOUS DISCUSSION***  
 
WE'LL TURN THE CORNER OVER THE WEEKEND AS THE TROUGH EXITS TO THE  
EAST AND IS REPLACED BY AN EVEN STRONGER HIGH PRESSURE RIDGE THAN  
WE HAD A COUPLE DAYS AGO. TEMPS WILL NUDGE UPWARD SATURDAY BUT  
BIGGER JUMPS SUNDAY AS THE RIDGE BUILDS.  
 
   
LONG TERM
 
(MON-THU)  
 
THE RIDGE WILL STRENGTHEN FURTHER MONDAY AND PEAK EARLY TUESDAY.  
WARMER VALLEY HIGHS EXPECTED TO CLIMB INTO THE LOWER TRIPLE DIGITS  
(100-103). FOR COASTAL AREAS GRADIENTS DO TREND OFFSHORE BUT NOT  
REALLY ENOUGH TO OFFSET THE MARINE LYR IMPACTS. STILL, INLAND  
COASTAL AREAS SHOULD REACH THE MID TO HIGH 80S EARLY NEXT WEEK.  
 
THE RIDGE STARTS WEAKENING TUESDAY, THOUGH INITIAL COOLING SHOULD  
BE CONFINED TO NORTHERN AREAS. FOR SOUTHERN AREAS HIGH TUESDAY  
SHOULDN'T BE MUCH DIFFERENT THAN MONDAY AND POSSIBLY EVEN A DEGREE  
OR TWO WARMER ACROSS THE INTERIOR. BEYOND TUESDAY MODELS DIFFER  
WITH RESPECT TO THE PATTERN, WITH THE GFS SHOWING JUST A SLIGHT  
COOL DOWN MID TO LATE WEEK THEN TURNING WARMER AGAIN BY NEXT  
WEEKEND. THE ECMWF SHOWS A CONTINUED COOLING TREND THROUGH THE  
PERIOD. HAVE TRENDED TOWARDS THE WARMER GFS SOLUTION AS THAT SEEMS  
TO HAVE BEEN THE BETTER PERFORMER LATELY.  
 

 
   
AVIATION
 
25/2355Z  
 
AT 2330Z AT KLAX... THE MARINE INVERSION WAS AROUND 1500 FEET  
DEEP. THE TOP OF THE INVERSION WAS NEAR 3900 FEET WITH A  
TEMPERATURE OF ABOUT 24 DEGREES CELSIUS.  
 
LOW CLOUDS LINGERING ALONG IMMEDIATE COASTAL SECTIONS OF LA COAST  
AND CENTRAL COAST LATE THIS AFTERNOON WHICH WILL RESULT IN EARLIER  
ARRIVAL TIMES OF CIGS FOR COASTAL TAFS. MARINE LAYER DEPTH  
EXPECTED TO DEEPEN TO AROUND 2000 FEET BY FRIDAY MORNING. THIS  
WILL BRING INCREASED PROBABILITY OF CIGS REACHING VALLEY TAF  
LOCATIONS. FOR NORTHERN TAF'S, LOOK FOR MOSTLY IFR/LIFR CIGS  
WHILE SOUTHERN TAF WILL HAVE MOSTLY MVFR CIGS. THERE IS A CHANCE  
OF CIGS LINGERING ACROSS COASTAL TAF SITES THROUGH FRIDAY  
AFTERNOON. SMOKE CONTINUES IN NORTHERN SAN LUIS OBISPO COUNTY  
FROM THE CHIMNEY FIRE AND IN SANTA BARBARA AND WESTERN VENTURA  
COUNTIES FROM THE REY FIRE.  
 
KLAX... HIGH CONFIDENCE IN 00Z TAF. WITH LOW CLOUDS ADVANCING  
QUICKLY LATE THIS AFTERNOON, LOOKING FOR SCT-BKN015 CONDITIONS TO  
PERSIST THROUGH 04Z, THEN MORE WIDESPREAD MVFR CIGS EXPECTED AFTER  
06Z. THERE IS A 20 PERCENT CHANCE OF MVFR CIGS LINGERING THROUGH  
THE AFTERNOON HOURS ON FRIDAY.  
 
KBUR... HIGH CONFIDENCE IN THE 00Z TAF. EXPECTING MVFR CIGS  
TO REACH KBUR LATE TONIGHT INTO FRIDAY MORNING, HOWEVER THERE  
IS SOME UNCERTAINTY IN ARRIVAL TIME. THERE IS ALSO A 20 PERCENT  
CHANCE OF IFR CIGS.  
 

 
   
MARINE...25/800 PM
 
 
CONDITIONS WILL REMAIN BELOW ADVISORY LEVELS THROUGH SATURDAY.  
WINDS ACROSS THE OUTER WATERS WILL STRENGTHEN LATE SATURDAY AND  
SMALL CRAFT ADVISORIES MAY BE NEEDED FOR SOME AREAS BY SUNDAY.  
 
PATCHY FOG WILL BE WIDESPREAD ACROSS THE COASTAL WATERS THROUGH  
SATURDAY...MAINLY DURING THE OVERNIGHT THROUGH MORNING HOURS.  
 

 
   
LOX WATCHES/WARNINGS/ADVISORIES
 
 
CA...NONE.  
PZ...NONE.  
 

 
 

 
 
PUBLIC...GOMBERG.MW  
AVIATION...GOMBERG  
MARINE...SMITH  
SYNOPSIS...SIRARD  
 
WEATHER.GOV/LOSANGELES  
 
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