SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
AFDLOX 950 PM PST TUE MAR 26 2002
SOME PATCHY LOW CLOUDS DEVELOPED OVER THE SBA COUNTY CENTRAL COAST
THIS EVENING...AND THERE WERE SOME HI CLOUDS LINGERING OVER SLO/SBA
COUNTIES...OTHERWISE MOSTLY CLEAR SKIES COVERED THE DISTRICT THIS
EVENING. MARINE INVERSION AROUND 1000 FEET AT VBG AND 500 FEET OR
LESS OVER L.A. COUNTY COAST ACCORDING TO ACARS SOUNDINGS FROM LAX AND
LGB. MESO-ETA FORECASTS A WEAK EDDY SHOULD DEVELOP LATE TONIGHT...
WHICH SHOULD BRING IN SOME LOW CLOUDS AND FOG INTO THE L.A. COUNTY
COAST AND UP TO THE VTU COUNTY COAST BY DAYBREAK.
UPPER LOW NEAR 27N/128W WAS DRIFTING SLOWLY SOUTHEAST THIS EVENING.
THE MODELS INITIALIZED THIS FEATURE WELL...WITH A SECOND UPPER LOW TO
THE NORTHEAST OF THE MAIN UPPER LOW. THESE TWO LOWS ARE FORECAST TO
COMBINE INTO ONE LATER TONIGHT AND MOVE EAST TO NEAR 30N/121W SAT
AFTERNOON...AND SLOWLY EAST ONLY TO NEAR 30N/117W BY SUN AFTERNOON.
THESE POSITIONS ARE SEVERAL HUNDRED MILES SOUTH OF THE DISTRICT.
CANNOT REALLY SEE A KICKER THAT WOULD PUSH THE UPPER LOW EASTWARD OVER
THE WEEKEND...SO THE MODELS MAY BE A TAD TOO QUICK WITH ITS MOVEMENT.
AT ANY RATE...THE MODELS FORECAST SOME MID AND HI LEVEL MOISTURE
ASSOCIATED WITH THE UPPER LOW TO MOVE INTO THE DISTRICT...BUT ITS
PRIMARY EFFECT ON THE LOCAL WEATHER SHOULD BE A DEEPENING MARINE LAYER
AND THE SPINNING UP OF A WEAK EDDY. SOME LIGHT SHOWERS OR DRIZZLE
WILL BE POSSIBLE ESPECIALLY OVER L.A./VTU COUNTIES LATER WED NITE AND
THU. SLO/SBA COUNTIES SHOULD BY DRY AND QUITE MILD AS SOME LIGHT
OFFSHORE FLOW WILL BE POSSIBLE DUE TO THE UPPER LOW'S POSITION.
THE UPPER LOW IS FORECAST TO PUSH EAST QUICKLY...AGAIN POSSIBLY TOO
QUICK...ON FRIDAY AND SATURDAY...AS AN UPPER RIDGE BUILDS OFF THE
COAST. THE UPPER RIDGE HOWEVER IS THEN FORECAST TO BE UNDERCUT BY A
WEAK UPPER TROF BY SATURDAY...THEN THE LATEST AVN MOVES THE UPPER
RIDGE FARTHER WEST SUN WITH AN UPPER TROF APPROACHING THE DISTRICT
FROM THE NORTHWEST ON SUN. DRY WEATHER WILL PREVAIL THRU THE WEEKEND...
WITH TEMPERATURES WARMING UP NICELY MAINLY OVER INLAND SECTIONS...BUT
THE COAST ESPECIALLY SHOULD HAVE ITS WARMING CURTAILED BY ONSHORE
FLOW AND POSSIBLE SOME MARINE LAYER INFLUENCE.
ALTHO PATCHY LOW CLOUDS WERE ALONG THE SBA COUNTY CENTRAL COAST...IT
IS DIFFICULT TO SAY IF THE LOW CLOUDS ARE JUST TEMPORARY OR WILL
EXPAND OVERNIGHT. SATELLITE TRENDS SUGGEST THEY MAY ONLY BE THERE FOR
A WHILE THIS EVENING AS AN OFFSHORE TREND WAS NOTED IN THE LOW CLOUDS
OFF THE CENTRAL COAST. WILL OPT TO LEAVE ZONES AS IS. BALANCE OF THE
FORECAST LOOKS VERY REASONABLE...THEREFORE NO ZONE UPDATES ARE PLANNED
THIS EVENING.
LAX 0012. SIRARD
.LOX...NONE.