512 
FXUS66 KLOX 290335
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
830 PM PDT MON JUN 28 2010

.SYNOPSIS...

AS THE UPPER HIGH MOVES EAST BY WEDNESDAY...A TROUGH ADVANCES ACROSS 
THE EASTERN PACIFIC...LASTING INTO EARLY NEXT WEEK. THE OVERNIGHT 
COASTAL CLOUDS AND FOG WILL PERSIST AND TEMPERATURES WILL REMAIN 
SLIGHTLY BELOW THE SEASONAL NORMALS THROUGH THE WEEK. A SLIGHT 
WARMING TREND IS EXPECTED OVER THE WEEKEND.

&&

.SHORT TERM (TODAY-THU)...THE 00Z NAM MODEL DATA WAS SHOWING A FEW 
DIFFERENCES FROM THE PREVIOUS MODEL RUN. THE 950 MB TEMPERATURES WERE 
SHOWING A SLIGHT COOLING FOR TUESDAY AS COMPARED TO MONDAY...WHEREAS 
THE FORECAST CALLS FOR A BIT OF WARMING. THE NEXT SHIFT MAY WANT TO 
REVIEW THE LATEST DATA TO CONFIRM WHETHER ANY TEMPERATURE ADJUSTMENT 
MIGHT BE NECESSARY. CURRENT THINKING IS THAT THE DIFFERENCES ARE 
RATHER MINOR AND LITTLE TEMPERATURE CHANGE SHOULD BE EXPECTED INTO 
TUESDAY. LINGERING MOISTURE OVER THE MOUNTAINS MAY BE ENOUGH FOR 
PARTLY CLOUDY SKIES AT THE MOST ON TUESDAY...BUT THE RESULTS MONDAY 
AFTERNOON WERE QUITE UNDERWHELMING. 

FOR TUESDAY NIGHT AND WEDNESDAY...LOW LEVEL MOISTURE PROGS 
DEFINITELY SHOW LESS INLAND PENETRATION OF THE LOW CLOUDS AND FOG 
DURING THIS PERIOD ALONG WITH WARMER 950 MB TEMPERATURES SO THE 
CURRENT TREND OF WARMER TEMPERATURES FOR WEDNESDAY STILL LOOKS GOOD 
IN SPITE OF THE EXISTENCE OF A WEST COAST TROUGH. THIS SCENARIO 
LOOKS FAIRLY PLAUSIBLE SINCE THE ACTUAL HEIGHTS OVER THE FORECAST 
AREA ARE A TAD HIGHER BY THIS TIME. 

BY WEDNESDAY NIGHT AND THURSDAY...THE 950 MB TEMPERATURES...500 MB 
HEIGHTS AND LOW LEVEL MOISTURE PROG LOOK VERY SIMILAR FOR NO CHANGE 
IN TEMPERATURES ANTICIPATED AT THIS TIME. 

.LONG TERM (FRI-MON)...A TROF IS EXPECTED TO PERSIST ACROSS THE WEST 
COAST THROUGH EARLY NEXT WEEK, THOUGH HEIGHTS/THICKNESSES DO REBOUND 
SOMEWHAT SAT/SUN. OVERALL, THOUGH, NOT MUCH CHANGE THROUGH MONDAY 
WITH TYPICAL MARINE LYR CLOUDS REACHING THE VALLEYS OVERNIGHT AND 
CLEARING TO THE COAST BY MID MORNING/EARLY AFTERNOON.

&&

.AVIATION...29/0250Z.
THE MARINE CLOUDS WERE MARCHING AGGRESSIVELY INTO THE COASTAL 
SECTIONS THIS EVENING WITH A MARINE LAYER DEPTH OF AROUND 2000 FEET. 
COASTAL SECTIONS SOUTH OF POINT CONCEPTION CAN EXPECT MVFR TO IFR 
CEILINGS...COASTAL SECTIONS NORTH OF POINT CONCEPTION CAN EXPECT IFR 
TO LIFR CEILINGS AND VALLEY TAFS WILL SEE IFR CEILINGS.

KLAX...GOOD CONFIDENCE IN MVFR TO IFR CEILINGS THROUGH TUESDAY 
MORNING WITH CLEARING IN THE EARLY TO MID AFTERNOON.

KBUR...GOOD CONFIDENCE IN MOSTLY IFR CEILINGS ARRIVING SHORTLY AND 
LASTING UNTIL MID TO LATE MORNING ON TUESDAY. 

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
SMALL CRAFT ADVISORY (SEE LAXMWWLOX).

&&

$$

PUBLIC...SWEET/WOFFORD
AVIATION...SWEET
SYNOPSIS...SETO

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