360 
FXUS66 KLOX 291018
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
300 AM PDT TUE SEP 29 2015

.SYNOPSIS...

TEMPERATURES WILL REMAIN SLIGHTLY ABOVE NORMAL THROUGH MID-WEEK WITH 
A TROUGH TO THE WEST AND A RIDGE TO THE EAST. THE TROUGH OF LOW 
PRESSURE WILL MOVE THROUGH THE AREA ON THURSDAY...BRINGING SLIGHTLY 
COOLER CONDITIONS. SURFACE HIGH PRESSURE WILL BUILD INTO THE GREAT 
BASIN BY LATE WEEK...POSSIBLY RESULTING IN WEAK OFFSHORE FLOW AND 
WARMER...DRIER CONDITIONS FOR THE WEEKEND.

&&

.SHORT TERM (TODAY-THU)... NOT MUCH CHANGE SYNOPTICALLY TODAY AND 
TOMORROW WITH AN UPPER HIGH TO THE SE AND AN UPPER LOW TO THE NW. 
SRN CA SITS BETWEEN THESE TWO FEATURES AND DRY SW FLOW FLOW WILL 
PERSIST FOR THE NEXT 48 HOURS. A LITTLE SFC HIGH BUILT INTO THE SAN 
JOAQUIN VLY LAST NIGHT AND HAS CREATED OFFSHORE TRENDS. THESE 
OFFSHORE TRENDS HAVE GREATLY INHIBITED THE MARINE LAYER STRATUS FROM 
FORMING SOUTH OF POINT CONCEPTION AND THERE WILL ONLY BE A FEW 
PATCHES OF STRATUS THIS MORNING. HGTS ARE ABOUT THE SAME SO THE 
OFFSHORE TRENDS SHOULD BRING A DEGREE OR SO OF WARMING TO THE VTA 
AND LA COASTS AND VLYS. THERE IS A GOOD MARINE LAYER CLOUD DECK 
NORTH OF POINT CONCEPTION WITH SOME DENSE FOG THROWN IN TO BOOT. MAX 
TEMPS FOR SLO AND WESTERN SBA COUNTY WILL BE A DEGREE OR SO COOLER 
THAN YDY.

HIGH PRESSURE CONTINUES TO OUR NORTH AND IT WILL SET UP A LITTLE 
SUNDOWNER FOR THE SBA SOUTH COAST. THERE WILL LIKELY BE MORE CLOUDS 
ACROSS THE VTA AND L.A. COUNTY COASTS WITH SIMILAR AMOUNTS ACROSS 
THE CENTRAL COAST.

NOT TOO MUCH EXCITEMENT ON WEDNESDAY. MAX TEMPS WILL BE DOWN A FEW 
DEGREES FROM TODAYS NUMBERS SKIES WILL BE PARTLY CLOUDY NORTH OF 
POINT CONCEPTION AS SOME MID LEVEL CLOUDS STREAM OVERHEAD IN THE SW 
FLOW.

EVEN LESS MARINE LAYER WEDNESDAY NIGHT AS OFFSHORE FLOW CONTINUES 
AND AN EVEN STRONGER SUNDOWNER SETS UP OVER THE SBA SOUTH COAST.

A TROF MOVES THROUGH THE AREA ON THURSDAY. UP UNTIL TODAY EVERY MDL 
FORECASTED A DRY TROF PASSAGE BUT NOW THE NAM AND THE EC SHOW SOME 
RAIN OVER THE NW TIP OF SLO COUNTY. WANT TO SEE TWO CONSECUTIVE 
RUNS WITH RAIN BEFORE PUTTING IT INTO THE OFFICIAL FORECAST BUT FOR 
SURE WILL MONITOR IT. OTHERWISE SKIES WILL BE PARTLY CLOUDY AND MAX 
TEMPS WILL COOL.

.LONG TERM (FRI-MON)... A LITTLE RIDGE POPS UP ON FRIDAY AND MAX 
TEMPS WILL JUMP UP NICELY EVERYWHERE.

THE MDLS NOW AGREE ON THE SATURDAY FORECAST FOR SRN CA (NRN CA - NOT 
SO MUCH) BOTH THE EC AND GFS QUICKLY SHUNT THE RIDGE OFF TO THE WEST 
AS A LONG WAVE TROF RETROGRADES IN FROM THE EAST. STILL FAVORING THE 
GFS FCST WHICH SHOWS A DEGREE OF WARMING OVER THE AREA. THE EC HAS 
MUCH LOWER HGTS AND IF IT IS CORRECT THE MAX TEMPS WOULD COOL.

ON SUNDAY THE GFS ROLLS THE RETROGRADING TROF OVER SRN CA AND HGTS 
FALL TO 573 DM. THE EC ON THE OTHER HAND MOVES A BIG STOMPING UPPER 
LOW THROUGH THE STATE AND HGTS FALL TO 565 DM. MAX TEMPS WILL FALL 
BUT PROBABLY THE EC IS A LITTLE TOO COOL. THE EC BRINGS SOME SHOWERS 
TO THE AREA BUT THE WEAK AND MORE REALISTIC GFS IS DRY AND USED IT 
FOR THE FCST. RIGHT NOW OFFSHORE FLOW IS FCST AND THIS MIGHT ALLOW 
MAX TEMPS TO BE A LITTLE WARMER THAN THEY WOULD BE OTHERWISE ACROSS 
THE VTA AND LA MTNS.

THERE WILL BE STILL BE PLENTY OF COOLISH AIR LEFT OVER BUT THE GFS 
HAS PRETTY ROBUST OFFSHORE FLOW SETTING UP WHICH WOULD ALLOW THE 
COASTS AND VLYS TO WARM ADIABATICALLY. THE INTERIOR WILL BE A COUPLE 
OF DEGREES WARMER THEN SUNDAY AS HGTS REBOUND IN THE WAKE OF THE 
TROF.

&&

.AVIATION...

29/0530Z
 
THE MARINE LAYER AT KLAX AT 0900Z WAS  FEET DEEP AND THE INVERSION 
TOP WAS NEAR FEET WITH A TEMP OF 26 DEGREES C.

KLAX...

KBUR...

&&

.MARINE... 

28/800 PM

THERE IS A 20-30 PERCENT CHANCE OF NORTHWEST WIND GUSTS REACHING 25 
KT ACROSS PORTIONS OF THE OUTER WATERS THIS EVENING THROUGH TUESDAY 
NIGHT. OTHERWISE...CONDITIONS WILL REMAIN BELOW ADVISORY LEVELS 
ACROSS THE COASTAL WATERS THROUGH THE PERIOD. THE WINDS WILL 
INCREASE ON WEDNESDAY AND A SMALL CRAFT ADVISORY IS LIKELY TO BE 
ISSUED FOR ALL OF THE OUTER WATERS WEDNESDAY THROUGH FRIDAY. 

&&

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

&&

$$

PUBLIC...RORKE
AVIATION/MARINE...BRUNO
SYNOPSIS...

WWW.WEATHER.GOV/LOSANGELES