Area Forecast Discussion
Issued by NWS Los Angeles, CA

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FXUS66 KLOX 041126 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
325 AM PST WED MAR 4 2015

...UPDATED AVIATION DISCUSSION...

.SYNOPSIS...

HIGH PRESSURE ALOFT WILL BUILD IN OVER THE REGION THROUGH THE
WEEKEND AND BRING WARMER TEMPERATURES TO THE AREA. TEMPERATURES
WELL ABOVE SEASONAL NORMALS WILL LINGER INTO EARLY NEXT
WEEK...THEN A COOLING TREND WILL ESTABLISH AS A SERIES OF UPPER-
LEVEL TROUGHS OF LOW PRESSURE APPROACH THE AREA.

&&

.SHORT TERM (TODAY-FRIDAY)...

THE LATEST WATER VAPOR IMAGERY INDICATES A SHORTWAVE TROUGH OVER
THE AREA THIS MORNING WITH A LARGE RIDGE OF HIGH PRESSURE OVER THE
EASTERN PACIFIC OCEAN. ALTHOUGH WEAK...ONSHORE FLOW IS ATTEMPTING
TO HANG ON ACROSS THE AREA THIS MORNING. FOG PRODUCT IMAGERY AND
SURFACE OBSERVATIONS DOES INDICATE PATCHES OF FOG OVER THE
CENTRAL COAST. BETTER FOG COVERAGE IS OCCURRING OVER THE SAN LUIS
OBISPO COUNTY VALLEYS THIS MORNING AND THIS AREA IS EXPANDING.
LOCALLY DENSE FOG CAN BE EXPECTED OVER THE SAN LUIS OBISPO COUNTY
VALLEYS AS THE MORNING PROGRESSES.

THE MAIN STORY IS THE WARMING TREND FOR LATE WEEK AS A LARGE
BLOCKING RIDGE OF HIGH PRESSURE OVER THE EASTERN PACIFIC OCEAN
BUILDS OVER THE AREA. A GRADUAL WARMING TREND WILL OCCUR TODAY AND
THURSDAY...BUT THE OMEGA BLOCK RIDGE REALLY TAKES CONTROL OF THE
WEATHER PATTERN FOR FRIDAY. TEMPERATURES SEEM IN LINE WITH LOCAL
TEMPERATURES STUDIES AND A FEW MINOR TWEAKS WERE MADE MAINLY TO COOL
OVERNIGHT LOW TEMPERATURES IN THE WIND SHELTERED AREAS AND INCREASE
OVERNIGHT LOW TEMPERATURES IN THE FOOTHILLS.

.LONG TERM (SATURDAY-TUESDAY)...

HIGH PRESSURE WILL KEEP A WARM AIR MASS IN PLACE THROUGH THE
WEEKEND...THEN A SERIES OF TROUGHS OF LOW PRESSURE WILL APPROACH
THE WEST COAST. TEMPERATURES WELL ABOVE SEASONAL NORMALS WILL
LINGER INTO EARLY NEXT WEEK. A SLIGHT COOLING TREND COULD START
TAKING SHAPE ALONG THE COAST ON SUNDAY...WITH A MORE PRONOUNCED
COOLING TREND DEVELOPING BETWEEN MONDAY AND TUESDAY. SKIES SHOULD
BE MOSTLY CLEAR...EXCEPT FOR SOME HIGH LEVEL CLOUDINESS STREAMING
OVER THE AREA. IT IS POSSIBLE THOUGH THAT PATCHY DENSE FOG COULD
DEVELOP ON MONDAY MORNING ALONG THE COAST AND AGAIN ON TUESDAY.

&&

.AVIATION...04/1125Z...

AT 1115Z...THERE WAS NO MARINE INVERSION AT KLAX.

OVERALL...HIGH CONFIDENCE IN THE 12Z TAF PACKAGE. OTHER THAN SOME
VLIFR CONDS THIS MORNING AT KPRB...AND MVFR VSBYS AT KSMX...WILL
ANTICIPATE VFR CONDS FOR THE AREA THROUGH THE TAF PERIOD. WEAK
OFFSHORE FLOW TODAY MAY GENERATE SOME TURBULENCE/LLWS ACROSS THE
VALLEYS AND FOOTHILLS THROUGH MID-AFTERNOON TODAY.

KLAX...HIGH CONFIDENCE IN THE 12Z TAF. VFR CONDS ANTICIPATED THROUGH
THE TAF PERIOD.

KBUR...HIGH CONFIDENCE IN THE 12Z TAF. VFR CONDS ANTICIPATED THROUGH
THE TAF PERIOD. THERE IS A 30% CHANCE OF SOME LGT-OCCASIONALLY MDT
TURBULENCE/LLWS 12Z TO 22Z TODAY.

&&

.MARINE...04/200 AM.

FOR THE OUTER WATERS...HIGH CONFIDENCE IN NORTHWEST TO NORTH WINDS
DROPPING BELOW SMALL CRAFT ADVISORY LEVELS THIS MORNING...AND CONTINUING
BELOW SMALL CRAFT THRESHOLDS THROUGH FRIDAY. FOR SATURDAY AND SUNDAY
THE NORTHWEST WINDS MAY INCREASE A BIT...WITH A CHANCE OF WINDS
INCREASING TO SMALL CRAFT ADVISORY THRESHOLDS.

FOR THE INNER WATERS...HIGH CONFIDENCE IN WINDS REMAINING BELOW SMALL
CRAFT ADVISORY THRESHOLDS THROUGH SUNDAY. TODAY THROUGH FRIDAY...THERE
WILL BE SOME NORTHEASTERLY FLOW DURING THE NIGHT THROUGH EARLY
AFTERNOON TIME FRAME. AT THIS TIME...THESE NORTHEAST WINDS ARE
ANTICIPATED TO REMAIN WEAK...BUT THERE IS A 20% CHANCE OF WINDS
REACHING SMALL CRAFT ADVISORY THRESHOLDS FROM VENTURA SOUTH TO SANTA
MONICA.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
NONE

&&

$$

PUBLIC...HALL
AVIATION...RAT
MARINE...RAT
SYNOPSIS...HALL

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