Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 051706 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1005 AM PDT SUN JUL 5 2015

...UPDATED AVIATION DISCUSSION...

LOW PRESSURE WILL CAUSE LOW CLOUDS AND FOG IN COASTAL AND MOST
VALLEY AREAS THROUGH TUESDAY...WITH TEMPERATURES NEAR TO SLIGHTLY
BELOW NORMAL. LOW PRESSURE WILL MOVE INTO CENTRAL CALIFORNIA
WEDNESDAY THROUGH FRIDAY WITH BELOW NORMAL TEMPERATURES. WARMING IS
EXPECTED NEXT WEEKEND AS LOW PRESSURE MOVES EAST OF THE REGION.

&&

.UPDATE...STRATUS REMAINS IN ALL COASTAL AND MANY VALLEY AREAS AT
THIS TIME. WITH STRONG ONSHORE GRADIENTS UP TO NEAR 9 MB BETWEEN
KLAX AND KDAG THIS AFTERNOON AND A STRONG INVERSION IN PLACE
...EXPECT CLEARING TO BE SLOW ONCE AGAIN NEAR THE COAST.  SINCE THE
AIRMASS IS BASICALLY THE SAME AS YESTERDAY...THE MORNING TEMPS ARE A
REPEAT OF YESTERDAY WITH THE EXCEPTION OF THE VALLEYS THAT ARE
SEEING THE STRATUS THIS MORNING WHICH ARE RUNNING ABOUT 5 DEGREES
COOLER.

*** FROM PREVIOUS DISCUSSION ***

EXPECT CLOUDS TO LINGER ALL DAY AT SOME BEACHES FROM SRN SBA COUNTY
THROUGH L.A. COUNTY. MAX TEMPS SHOULD BE DOWN A FEW MORE DEGREES IN
MOST AREAS TODAY. GUSTY SW TO W WINDS ARE EXPECTED THROUGH THE
SOLEDAD PASS AND ACROSS THE ANTELOPE VALLEY THIS AFTERNOON AND
EVENING...BUT AT THIS POINT...EXPECT WINDS TO REMAIN JUST BELOW
ADVISORY LEVELS. THE WRF CONTS TO SHOW A POCKET OF STRONGLY NEGATIVE
LIFTED INDEX VALUES ACROSS THE MTNS...ESPECIALLY IN VTU COUNTY...BUT
WITH LITTLE IN THE WAY OF MOISTURE WITH WHICH TO WORK...EXPECT SOME
BUILDUPS AT MOST TODAY.

THE UPPER LOW WELL TO THE WEST OF POINT CONCEPTION IS FORECAST TO
MOVE LITTLE THRU TUE. EXPECT MOSTLY MINOR DAY TO DAY CHANGES IN THE
WEATHER ACROSS THE REGION THRU TUE...WITH NIGHT/MORNING LOW CLOUDS
AND FOG IN COASTAL AND MOST VALLEY LOCATIONS...AND SLOW CLEARING
NEAR THE BEACHES. MAX TEMPS SHOULD NOT DIFFER TOO MUCH FROM DAY TO
DAY...ALTHOUGH THERE MAY BE SOME SLIGHT COOLING EACH DAY IN THE MTNS
AND DESERTS. THE WRF DOES SHOW SOME INCREASED N-S GRADIENTS ACROSS
SBA COUNTY MONDAY AND TUESDAY...SO EXPECT SOME GUSTY NW TO N WINDS
THROUGH AND BELOW PASSES AND CANYONS OF SRN SBA COUNTY LATE EACH
AFTERNOON AND EVENING. AS A RESULT...EXPECT MUCH LATER ARRIVAL OF
ANY STRATUS TO THE S COAST OF SBA COUNTY MON NIGHT AND TUE NIGHT.

.LONG TERM (WED-SAT)...THE UPPER LOW WILL BEGIN TO MOVE SLOWLY EWD
TUE NIGHT AND WED. THE MARINE LAYER SHOULD DEEPEN...AND NIGHT THRU
MORNING LOW CLOUDS MAY PUSH INTO THE LOWER COASTAL SLOPES. THERE
COULD ALSO BE SOME DRIZZLE. MAX TEMPS SHOULD BE DOWN A BIT MORE IN
MOST AREAS. THE UPPER LOW IS FORECAST TO TRACK INTO MRY OR SLO
COUNTY ON THU. THE MARINE LAYER WILL REMAIN DEEP...WITH NIGHT THRU
MORNING CLOUDS TO THE COASTAL SLOPES AND SOME DRIZZLE POSSIBLE.
THERE MAY ONLY BE PARTIAL CLEARING WEST OF THE MTNS ON THU. WOULD
NOT BE SURPRISED IF THERE IS SOME MEASURABLE LIGHT RAIN IN SOME
AREAS ON THU...PARTICULARLY ACROSS SLO AND SBA COUNTIES AND IN THE
FOOTHILLS OF L.A. COUNTY. MAX TEMPS SHOULD BE DOWN A COUPLE OF
DEGREES...WITH TEMPS GENERALLY WELL BELOW NORMAL FOR JULY. THE UPPER
LOW WILL LIFT NE AND WKN THU NIGHT AND FRI...BUT A TROUGH WILL HANG
BACK OVER THE REGION. THEREFORE...EXPECT THE MARINE LAYER TO REMAIN
FAIRLY DEEP...AND ANY WARMING SHOULD BE LIMITED. HEIGHTS WILL RISE
ACROSS THE REGION ON SAT AS A STRONG UPPER HIGH OVER THE S CENTRAL
US EXPANDS WWD. THIS SHOULD BRING SOME DECREASE IN THE MARINE LAYER
DEPTH...A REDUCTION IN NIGHT THROUGH MORNING STRATUS IN THE
VALLEYS...AND SOME WARMING TO MOST AREAS ON SAT.

&&

.AVIATION...05/1705Z...

AT 1607Z...THE MARINE INVERSION AT KLAX WAS BASED AT 2700 FEET. THE
TOP OF THE INVERSION WAS AT 4900 FEET WITH A TEMPERATURE OF 23
DEGREES CELSIUS.

OVERALL...MODERATE TO HIGH CONFIDENCE IN 18Z TAF PACKAGE. CURRENT
MVFR CIGS ARE DISSIPATING TO THE COAST THIS MORNING...AND MOST SITES
WILL BE VFR THIS AFTERNOON EXCEPT FOR SOME COASTAL TAF SITES. FOR
TONIGHT...HIGH CONFIDENCE IN RETURN OF MVFR (AND ISOLATED IFR) CIGS
AND VSBYS...BUT ONLY MODERATE CONFIDENCE IN TIMING (+/- 2 HOURS OF
CURRENT 02Z FORECAST).

KLAX...MODERATE CONFIDENCE IN 18Z TAF. THERE IS A 30% CHANCE THAT
MVFR CIGS WILL NOT DISSIPATE THIS AFTERNOON. HIGH CONFIDENCE IN
RETURN OF MVFR CIGS...AND MODERATE CONFIDENCE IN TIMING.

KBUR...MODERATE CONFIDENCE IN 18Z TAF. HIGH CONFIDENCE IN VFR CONDS
BY AFTERNOON AND CONTINUING THROUGH THIS EVENING. HIGH CONFIDENCE IN
RETURN OF MVFR CIGS (WITH A 30% CHANCE OF IFR CIGS DEVELOPING)...BUT
ONLY MODERATE CONFIDENCE IN TIMING (+/- 2 HOURS OF CURRENT 08Z
FORECAST).

&&

.MARINE...05/830 AM...

FOR THE OUTER WATERS...HIGH CONFIDENCE IN WEST TO NORTHWEST WINDS
REMAINING BELOW SMALL CRAFT ADVISORY LEVELS THROUGH MONDAY(ALTHOUGH
THERE MAY BE SOME LOCAL GUSTS TO 25 KT IN THE AFTERNOON AND EVENING
HOURS). SMALL CRAFT ADVISORY CONDITIONS WILL LIKELY DEVELOP TUESDAY
AND CONTINUE INTO WEDNESDAY OR THURSDAY.

FOR THE INNER WATERS...HIGH CONFIDENCE IN WESTERLY WINDS REMAINING
BELOW SMALL CRAFT ADVISORY LEVELS THROUGH MONDAY. WINDS WILL
INCREASE SOME STARTING MONDAY NIGHT. THERE WILL BE SMALL CRAFT
ADVISORY LEVEL GUSTS ACROSS WESTERN SECTIONS EACH AFTERNOON AND
EVENING THROUGH THURSDAY...AND THERE IS A CHANCE THE GUSTS COULD BE
WIDESPREAD ENOUGH FOR AN ADVISORY.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
NONE

&&

$$

PUBLIC...JLD/DB
AVIATION/MARINE...RAT
SYNOPSIS...SWEET

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