Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 202337 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
437 PM PDT WED AUG 20 2014

UPDATED AVIATION SECTION

.SYNOPSIS...

THERE IS A SLIGHT CHANCE OF THUNDERSTORMS THIS EVENING IN LOS
ANGELES COUNTY AND IN THE VENTURA COUNTY MOUNTAINS. THERE IS A
SLIGHT CHANCE OF THUNDERSTORMS TOMORROW AS WELL BUT PRIMARILY IN THE
MOUNTAINS OF LOS ANGELES AND VENTURA COUNTIES. AFTERNOON HIGH
TEMPERATURES WILL BE BELOW NORMAL THROUGH THE END OF THE WEEK WITH
LOW CLOUDS ALONG THE COAST AND IN ADJACENT VALLEYS. CLEARER SKIES
AND WARMER TEMPERATURES ARE EXPECTED FOR THE WEEKEND.

&&

.SHORT TERM (TODAY-FRI)...
THE UPPER LOW PRESSURE CENTERED JUST OFF THE LOS ANGELES COUNTY
COAST THIS AFTERNOON WILL SLOWLY DROP A BIT FARTHER SOUTH TONIGHT
THEN BEGIN TO EJECT EASTWARD TOMORROW.  THIS IS THE SYSTEM
RESPONSIBLE FOR SPINNING UP THE LINE OF THUNDERSTORMS SOUTHEAST OF
THE SERVICE AREA THIS MORNING AND AS IT SHIFTS... THE FLOW OF
PRECIPITABLE WATER WILL CRANK AROUND TO THE EAST AND NORTHEAST.
THIS WILL BRING A SLIGHT CHANCE OF THUNDERSTORMS INTO LOS ANGELES
COUNTY BY LATE THIS AFTERNOON.

GOOD INSTABILITY ACROSS THE SERVICE AREA WILL ENCOURAGE SOME
CONVECTIVE DEVELOPMENT WITH THE PROPER WIND FLOW.  HOWEVER A LACK OF
MOISTURE WILL KEEP DEVELOPMENT TO A MINIMAL LEVEL UNLESS AND UNTIL
THE LOW CENTER SHIFTS ENOUGH TO TIGHTEN THE GRADIENTS AND REALLY
PULL THE MOISTURE AROUND THE SYSTEM.  KEEPING A SLIGHT CHANCE OF
THUNDERSTORMS IN LOS ANGELES COUNTY AND IN THE VENTURA COUNTY
MOUNTAINS THIS AFTERNOON AND TONIGHT... BUT AM NOT EXPECTING MUCH IF
ANY PRECIPITATION.  WIND FROM DOWNDRAFTS AND DRY LIGHTNING ARE THE
PRIMARY CONCERNS.

BY TOMORROW THE LOW WILL HAVE SHIFTED TO THE SOUTHEAST AND A BETTER
PULL OF MOISTURE IS POSSIBLE THOUGH THE INSTABILITY IS SOMEWHAT
REDUCED.  THIS SHOULD KEEP ANY THUNDERSTORM DEVELOPMENT IN THE
VICINITY OF THE MOUNTAINS BUT ALL THINGS CONSIDERED IT IS A BETTER
SITUATION TO SQUEEZE OUT A LITTLE PRECIP IN THE SAN GABRIEL RANGE.
OTHER LOCATIONS HAVE A CHANCE OF DOWNDRAFTS AND DRY LIGHTNING MUCH
LIKE TODAY.

COASTAL LOW CLOUDS WILL CONTINUE THROUGH THE NEXT FEW DAYS AND WILL
CONTINUE TO PUSH WELL INLAND IN THE ADJACENT VALLEYS.  FRIDAY WILL
SEE A REDUCED THREAT OF CONVECTIVE WEATHER BUT THE MARINE CLOUDS
WILL KEEP HIGH TEMPERATURES REDUCED DUE TO LINGERING LOW CLOUDS.

.LONG TERM (SAT-TUE)...
A MIXED BAG THROUGH THE WEEKEND AND INTO NEXT WEEK.  HIGH PRESSURE
TRIES TO BUILD OVER THE AREA AND LOOKS TO BE EFFECTIVE IN KEEPING
THE NEXT LOW TO THE NORTH OF THE REGION.  GENERALLY... TEMPERATURES
WILL HOVER NEAR NORMAL READINGS AND THE MARINE CLOUDS WILL COME IN
ALONG THE COAST BUT NOT VERY FAR INLAND.  NO CONVECTIVE DEVELOPMENT
NOR STRONG WINDS ARE EXPECTED AT THIS TIME.

&&

.AVIATION...20/2337Z.

LOWER CONFIDENCE IS PACKAGE THAN PREVIOUSLY THOUGHT AS VFR
CONDITIONS HAVE DEVELOPED AT ALL TERMINALS THIS AFTERNOON. IFR TO
MVFR CONDITIONS WILL LIKELY RETURN BETWEEN 03Z AND 08Z. THERE IS A
CHANCE OF LIFR CONDITIONS BETWEEN 10Z AND 16Z AT TERMINALS NORTH OF
POINT CONCEPTION. THERE IS A 20 PERCENT CHANCE OF THUNDERSTORMS FOR
KPMD AND KWJF THROUGH 04Z.

KLAX...THERE IS A 80 PERCENT CHANCE OF MVFR CONDITIONS REDEVELOPING
BETWEEN 03Z AND 08Z. MVFR CONDITIONS SHOULD REMAIN AT KLAX THROUGH
AT 16Z...OR 18Z AT THE LATEST.

KBUR...THERE IS A 60 PERCENT CHANCE OF MVFR CONDITIONS...MAINLY
AFTER 07Z. VFR CONDITIONS SHOULD REDEVELOP BETWEEN 16Z AND 17Z.

&&

.MARINE...20/200 PM.

NO SIGNIFICANT WIND ISSUES ANTICIPATED ACROSS THE COASTAL WATERS FOR
THE NEXT SEVERAL DAYS.

THERE IS THE POSSIBILITY OF SOME ISOLATED THUNDERSTORMS ACROSS THE
SOUTHERN WATERS THROUGH THIS EVENING...WITH GUSTY WINDS AND CHOPPY
SEAS LIKELY WITH ANY THUNDERSTORMS.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
MARINE WEATHER STATEMENT (SEE LAXMWSLOX).

&&
$$

PUBLIC...KJ
AVIATION...SWEET
MARINE...SWEET

WWW.WEATHER.GOV/LOSANGELES









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