944 
FXUS66 KLOX 061220
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
520 AM PDT WED AUG 6 2014

UPDATED AVIATION SECTION

.SYNOPSIS...
A WEAK UPPER LEVEL LOW PRESSURE SYSTEM WILL BRING A SLIGHT CHANCE OF 
SHOWERS AND THUNDERSTORMS TO INTERIOR SAN LUIS OBISPO AND SANTA 
BARBARA COUNTIES THIS AFTERNOON AND EVENING. OTHERWISE...A LINGERING 
UPPER LEVEL TROUGH OF LOW PRESSURE WILL DEEPEN THE MARINE LAYER 
THROUGH THE WEEKEND WITH TEMPERATURES NEAR NORMAL.

&&

.SHORT TERM (TODAY-SAT)...
A WEAK EDDY HAS LIFTED THE MARINE LAYER UP TO ABOUT 1400 FEET. 
MARINE STRATUS HAS MOVED INTO MOST OF THE COAST AND VLY AREAS. BURN 
OFF WILL BE A LITTLE LATER THAN IT WAS YESTERDAY AS A RESULT OF A 
STRONGER INVERSION AND A BETTER ONSHORE GRADIENT.

THE MOST INTERESTING THING WEATHER WISE TODAY IS THE RETURN OF THE 
UPPER LOW THAT BROUGHT ALL OF SUNDAYS THUNDER ACTIVITY. THE LOW HAS 
MADE A LOOP UP TO THE SACRAMENTO AREA AND IS NOW LOOPING TO THE 
SOUTHEAST. IT IS CURRENTLY OVER THE BAY AREA. THE LOW IS MUCH WEAKER 
AND MUCH MUCH DRIER THAN IT WAS ON SUNDAY. STILL THE MAX PVA ASSOC 
WITH THIS LOW MOVES OVER SLO AND SBA COUNTIES THIS AFTERNOON CLOSE 
TO PEAK HEATING. THERE IS GOOD INSTABILITY WITH LOTS OF SUNSHINE AND 
THE COOL POOL OF AIR ALOFT WITH THE LOW AND SOME LIFT WITH THE WEAK 
PVA THE BIG MISSING INGREDIENT IS MOISTURE SO NOT A HIGH CHC OF 
AFTERNOON AND EVENING TSTMS FOR THE INTERIOR OF SLO AND SBA COUNTIES 
BUT AT LEAST A 20 PERCENT CHC.

THE UPPER LOW KICKS OUT TO THE EAST TONIGHT AND THIS WILL END ANY 
THREAT OF TSTMS. THE UPPER LOW IS REPLACED BY A BROAD WEST COAST 
TROF. THAT LASTS INTO SATURDAY. HGTS...GRADIENTS AND UPPER LEVEL 
FLOW ALL REMAIN ABOUT THE SAME THURSDAY THROUGH SATURDAY AND THE 
WEATHER WILL BE VERY SIMILAR FROM DAY TO DAY. THERE WILL BE A DEEPER 
THAN NORMAL MARINE LAYER WITH NIGHT THROUGH MORNING LOS CLOUDS 
COVERING THE COASTS AND MOST OF THE VLYS. MAX TEMPS WILL BE JUST A 
DEGREE OR TWO BLO NORMAL ACROSS THE INTERIOR BUT THE COASTS AND VLYS 
WILL BE 4 TO 8 DEGREES BLO NORMAL DUE TO THE DEEPER THAN NORMAL 
MARINE LAYER AND THE MODERATE ONSHORE FLOW. 

.LONG TERM (SUN-TUE)...
ALL MDLS HAVE NOW FLIPPED FLOPPED FROM THE EARLIER HOT TEMPS AND 
MONSOON FLOW FCST EARLIER AND NOW ALL AGREE THAT A LARGE CUT OFF LOW 
WILL SLOWLY APPROACH AND THEN MOVE THROUGH THE STATE. NO MOISTURE IS 
EVIDENT WITH THIS LOW SO PRECIPITATION CHANCES SEEM NEGLIGIBLE. WHAT 
THIS UPPER LOW WILL DO IS KEEP THE MARINE LAYER DEEP INTO THE VLY 
THROUGH THE PERIOD. MAX TEMPS WILL ALSO CONTINUE BLO NORMAL. KIND OF 
HARD TO TELL THIS FORECAST FROM A JUNE ONE ACTUALLY.

&&

.AVIATION...06/1220Z.

IFR TO MVFR CONDITIONS WILL CONTINUE AT MOST COASTAL AND VALLEY 
TERMINALS THROUGH AT LEAST 16Z. THERE IS A CHANCE OF IFR TO MVFR 
CONDITIONS LINGERING AT KSBA AND KOXR AS LATE AS 22Z.

KLAX...MVFR CONDITIONS SHOULD IMPROVE TO VFR BETWEEN ONE CATEGORY 
BETWEEN 16Z AND 17Z. THERE IS A 30 PERCENT CHANCE OF MVFR CONDITIONS 
LINGERING UNTIL 18Z.

KBUR..THERE IS A 60 PERCENT CHANCE OF MVFR CONDITIONS BETWEEN 14Z 
AND 16Z. AFTER 16Z...VFR CONDITIONS ARE EXPECTED THROUGHOUT THE 
PERIOD THROUGH AT LEAST 08Z. IFR CONDITIONS SHOULD REDEVELOP BETWEEN 
08Z AND 12Z THURSDAY.

&&

.MARINE...06/300 AM PDT.

LOCAL SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE NEAR POINT 
CONCEPTION AND ACROSS THE WESTERN PORTION OF THE SANTA BARBARA 
CHANNEL THROUGH THURSDAY EVENING. THERE IS A BETTER CHANCE OF SMALL 
CRAFT ADVISORY CONDITIONS BETWEEN FRIDAY AFTERNOON AND SUNDAY 
MORNING. 

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
HIGH RIP CURRENT RISK (SEE LAXSRFLOX).

&&

$$

PUBLIC...RORKE
AVIATION/MARINE...HALL
SYNOPSIS...SIRARD

WWW.WEATHER.GOV/LOSANGELES