000 
FXUS66 KLOX 220027 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
427 PM PST FRI DEC 21 2007

UPDATED AVIATION SECTION

.SHORT TERM...MADE MINOR CHANGES THROUGH THE PERIOD. HAVE ADJUSTED 
THE TIMING OF THE UPPER LEVEL CLOUD FIELD MOVING THROUGH THE 
AMPLIFYING RIDGE OVER THE AREA THROUGH THE PERIOD. OTHERWISE 
NORTHEAST WINDS WILL LIKELY GUST TO 35 MPH IN THE LOWER ELEVATIONS 
AND TO 55 MPH OVER THE EXPOSED RIDGES AND PEAKS TONIGHT...WINDS WILL 
VERY LIKELY RETURN SATURDAY NIGHT AS WELL. GUIDANCE WAS CONSISTENT 
WITH AMPLIFYING A RIDGE UPSTREAM WHILE THE UPPER LEVEL NORTH FLOW 
ACCELERATES OVER THE AREA SAT NIGHT WHICH WILL REINFORCE THE LOW 
LEVEL NORTH WINDS WHERE GUSTS 55 MPH OR GREATER OVER EXPOSED RIDGES 
AND PEAKS ARE POSSIBLE EARLY SUNDAY MORNING. MORNING LOW 
TEMPERATURES IN THE LOWER ELEVATIONS WERE AROUND 5 DEGREES BELOW 
NORMAL IN THE NORTH HALF OF THE AREA AND A COUPLE OF DEGREES ABOVE 
NORMAL IN THE SOUTH HALF THIS MORNING...WITH WINDS BEING LIGHT 
TONIGHT LOWS WILL COOL TO A COUPLE DEGREES BELOW NORMAL IN THE SOUTH 
HALF AND NEARLY 10 DEGREES BELOW NORMAL IN THE NORTH HALF. AIR MASS 
WILL CHANGE LITTLE THROUGH SUN AND EXCEPT FOR SCATTERED UPPER LEVEL 
CLOUD COVER OVERNIGHT LOWS WILL REMAIN BELOW NORMAL. AFTERNOON TEMPS 
IN THE LOWER ELEVATIONS RANGED FROM 5 DEGREES AT THE COAST TO 15 
DEGREES IN THE INLAND VALLEYS. AFTERNOON TEMPS WILL MODERATE THROUGH 
THE WEEKEND AS HEIGHTS/THICKNESSES BUILD...AND WARM TO NEAR NORMAL 
BY SUNDAY. WILL CONTINUE DRY MONDAY THOUGH THE ENSEMBLE WAS 
CONSISTENT WITH A TROUGH SKIRTING THE NORTHERN HALF OF THE AREA 
EARLY MONDAY...OTHERWISE OVERNIGHT TEMPS WILL LIKELY WARM TO OR 
ABOVE NORMAL MON MORNING.          

.LONG TERM...GUIDANCE WAS REASONABLY CONSISTENT WITH WEAK SYSTEMS 
MOVING THROUGH THE LONG WAVE RIDGE. WILL CONTINUE DRY AT THIS TIME 
WHILE A WEAK SYSTEM MOVES ASHORE WITHIN THE NORTH FLOW WEDNESDAY AND 
THE LATTER HALF OF FRIDAY. AVERAGE TEMPERATURES WILL PERSIST BELOW 
SEASONAL NORMAL THROUGH THE PERIOD WHILE A RELATIVELY COOL AND DRY 
PACIFIC HIGH PERSIST UPSTREAM.  


&&

.AVIATION...21/0027Z...VFR CONDITIONS ARE EXPECTED TO PERSIST AT ALL 
AIRFIELDS THROUGHOUT THE PERIOD. GUSTY NORTH TO NORTHEAST WINDS WILL 
CONTINUE AT THE MORE FAVORABLE LOCATIONS...SUCH AS KBUR AND KVNY. 
LLWS AND TURBULENCE WILL BE A PROBLEM IN THE VALLEYS AND HIGHER 
TERRAIN AREAS.

KLAX...VFR CONDITIONS EXPECTED TO PERSIST THROUGHOUT THE PERIOD. 
OFFSHORE WINDS SHOULD ESTABLISH WITHIN THE NEXT THREE TO FOUR HOURS 
THIS EVENING. IT POSSIBLE BETWEEN 03Z AND 05Z TIME PERIOD THAT 
NORTHEAST WINDS AT KLAX COULD EXCEED 10 KNOTS...BUT NOT LIKELY.

KBUR...VFR CONDITIONS EXPECTED TO PERSIST THROUGHOUT THE PERIOD. LOW 
LEVEL WIND SHEAR ISSUES COULD DEVELOP AT TIMES THIS EVENING AS WINDS 
ARE STRONG JUST OFF THE SURFACE.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY (SEE LAXNPWLOX).
SMALL CRAFT ADVISORY (SEE LAXCWFLOX).

&&

$$

PUBLIC...30
AVIATION...HALL

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