Forecast Discussions mentioning ACARS, received at FSL on 03/08/01

FAIRLY QUIET EVENING FOR A CHANGE ACROSS THE DISTRICT. MARINE LAYER TRYING TO GET REESTABLISHED. 00Z SOUNDINGS SHOW MARINE LAYER DEPTH AROUND 1000 FEET AT VBG. ACARS SOUNDINGS AROUND LAX AND LGB SHOW THE MARINE LAYER NEAR 2500 FEET. LOW CLOUDS INTO PORTIONS OF THE CENTRAL COAST THIS EVENING...AND HAVE LINGERED OVER THE SAN GABRIEL VALLEY. MORE LOW CLOUDS DEVELOPING OVER THE INNER COASTAL WATERS AROUND SAN CLEMENTE ISLAND. MESO-ETA FOR THE LAST SEVERAL RUNS SHOWING AN EDDY OVERNIGHT INTO THU MORNING. LOW CLOUD PATTERN ON THE FOG PRODUCT WOULD SUGGEST THIS IS DEVELOPING...AND WINDS AT LGB AND SLI WERE OUT OF THE SE THIS EVENING. GOOD CHANCE OF LOW CLOUD DEVELOPMENT OVERNIGHT ALONG LAX/VTU COUNTY COAST AND LINGERING FOR A WHILE THU MORNING. LATEST FOG PRODUCT SHOWING LOW CLOUDS IN SAN GABRIEL VALLEYS DISSIPATING. SOME LOW CLOUDS MAY PUSH BACK INTO THIS AREA LATE TONIGHT OR EARLY THU. THE LOW CLOUDS SHOULD BURN OFF BY MIDDAY THU. WILL UPDATE ZONES BY 945 PM TO ACCOUNT FOR THE LOW CLOUDS OVERNIGHT...AND USE MORE PESSIMISTIC WORDING OF LOW CLOUDS OVER COAST AND VLYS OF SLO/SBA COUNTIES OVERNIGHT AND THU MORNING.

GENERALLY FAIR WEATHER SHOULD PREVAIL THU AND THU NITE...WITH PERHAPS SOME MORE LOW CLOUDS ALONG THE COAST. NEXT PROBLEM TO DEAL WITH FOR THE DISTRICT IS ANOTHER UPPER LEVEL LOW MOVING INTO THE REGION FROM LATE FRIDAY INTO SAT MORNING. LATEST MODEL RUNS INDICATE THE UPPER LOW MAY WIND UP MOVING ALONG THE COAST OR EVEN INLAND OVER SOCAL. LATEST MESO-ETA CLOSER TO THE COAST...AVN A BIT FARTHER INLAND. ALSO...APPEARS THIS UPPER LOW WILL BE PROGRESSIVE AND MOVE FAIRLY QUICKLY EAST SAT. MOISTURE SOMEWHAT LACKING WITH THIS SYSTEM...SO AT THIS TIME MORE LIKE A SHOWERY EVENT COMING UP. LATER MODEL RUNS WILL GIVE US A BETTER PICTURE...AS RUN TO RUN CONSISTENCY HAS BEEN RATHER POOR.

IN THE EXTENDED...A BROAD UPPER TROF LINGERING OVER THE DISTRICT SHOULD GIVE THE REGION MORE SHOWERS SAT AND SUN. FAIR WEATHER WITH MORE SEASONABLE TEMPS IS EXPECTED TO RETURN MON AS AN UPPER HIGH BUILDS OFF THE W COAST WITH SOME OFFSHORE FLOW RETURNING TO THE DISTRICT.

LAX 0001. SIRARD.

.LAX...SMALL CRAFT ADVISORY...SEE LAXCWFLAX.



GHOST REMNANT OF A COLD FRONT IS APPROACHING CA NORTH COAST ATTM AND EXPECT IT TO PRODUCE NO RAIN. BUT THE UPPER TROUGH LOOKS SIGNIFICANT ENOUGH TO CONTINUE LIFTING THE MARINE STRATUS. AIRCRAFT REPORTS AT CEC SHOW THE STRATUS TOP HAS RISEN FROM 1200 TO 2000 FT DURING THE DAY WHICH EKA PROFILER CONFIRMS AND SHOWS THIS TREND CONTINUING. DEEPENING AND LIFTING OF THE STRATUS WILL LIKELY PRODUCE DRIZZLE AS THE FORECAST STATES...SO WILL LEAVE THAT AS IS WITH NO ZONE UPDATE EXPECTED TONIGHT. AM NOT SURE ABOUT CLOUD CEILINGS THOUGH AND WILL CONSIDER RAISING THEM IN TAFS IF THAT TREND CONTINUES. MARINE LAYER HAS BECOME DEEP ENOUGH TO BEGIN SPREADING INLAND EXCEPT IS CURRENTLY HARD TO CONFIRM THIS HAPPENING ON SATELLITE. COASTAL WATERS FORECAST IS ALSO IN GOOD SHAPE WITH MINOR FEW ADJUSTMENTS. GV POPS CEC 1102 EKA 1102 UKI 0003.

.EKA...SMALL CRAFT ADVISORY PT ST GEORGE TO PT ARENA OUT 60 NM.



DEALING WITH A WEAK CATALINA EDDY THIS MORNING...WHICH ACTUALLY APPEARS TO WANT TO HANG ON FOR THE NEXT COUPLE OF DAYS. GOOD NEWS IS THAT PRESSURE GRADIENTS ARE WEAK ACROSS THE CWA...LEADING TO ONLY A WEAK ONSHORE FLOW. IN ADDITION...VBG SOUNDING AND ACARS SOUNDINGS SHOW ONLY A WEAK INVERSION. SO THE FEELING HERE IS THAT MARINE LAYER SHOULD BURN OFF AROUND MIDDAY FOR THE CENTRAL COAST AND SBA COUNTY. FOG IN SOME OF THE INLAND VALLEYS OF VTU AND LA COUNTIES SHOULD BURN OFF BY LATE MORNING. CURRENT ZONES HAVE THE LOW CLOUDS/FOG HANDLED WELL FOR NOW. WILL UPDATE ZONES A LITTLE LATER THIS MORNING TO FRESHEN THE WORDING.

12Z MODELS BRINGING NEXT SYSTEM FARTHER INLAND...SO WILL BE TAKING A CLOSER LOOK AT ALLOCATION OF POPS FOR THE EARLY WEEKEND. MORE TO COME IN AFTN DISCUSSION.

LAX 000. MOYER.

.LAX...SMALL CRAFT ADVISORY...SEE LAXCWFLAX.



MARINE LAYER HAS MADE A SUDDEN RETURN TO THE AREA THIS MORNING... WITH BEST COVERAGE NORTH OF PT CONCEPTION. SURFACE OBS INDICATE WEAK EDDY ACROSS THE COASTAL WATERS...SUPPORTED BY 06Z HIGH-RES ETA. LATEST ACARS SOUNDINGS INDICATE INVERSION BASED AROUND 2000 FEET. EXPECT SOLID STRATUS COVERAGE TO CONTINUE NORTH OF PT CONCEPTION THIS MORNING...WITH STRATUS/FOG FILLING IN SOUTH OF PT CONCEPTION. WITH NO STRONG EDDY OR ONSHORE FLOW...WILL EXPECT STRATUS/FOG TO BURN OFF THIS AFTERNOON. TONIGHT/FRIDAY MORNING...ANOTHER ROUND OF MARINE LAYER EXCITEMENT...AS INVERSION SHOULD REMAIN AND MODELS INDICATE CONTINUED ONSHORE FLOW AND POSSIBLE EDDY.

BESIDES MARINE LAYER...FORECAST ATTENTION FOCUSES ON UPPER LOW THAT MODELS BEGIN TO DROP SOUTH ACROSS THE AREA FRIDAY AFTERNOON. 00Z MODELS HANDLE THE SYSTEM DIFFERENTLY THROUGH SATURDAY...WITH ETA KEEPING A TRACK CLOSER TO THE OCEAN THAN THE AVN. GIVEN THE VERY WEAK PERFORMANCE OF THE ETA IN RECENT WEEKS...INCLINED TO LEAN TO THE AVN SOLUTION. GIVEN THAT...UPPER LOW WILL START TO AFFECT THE CENTRAL COAST FRIDAY AFTERNOON...AND WILL INDICATE CHANCE SHOWERS FOR THOSE AREAS. OTHERWISE...FRIDAY SHOULD BE PARTLY CLOUDY.

THE COMBO OF MARINE INFLUENCE AND FALLING THICKNESSES...IN RESPONSE TO UPPER LOW...WILL ALLOW TEMPS TO COOL THROUGH FRIDAY.

FOR EXTENDED...FRIDAY NIGHT/SATURDAY SHOULD BE BEST CHANCE FOR PRECIP ACROSS THE AREA. ALTHOUGH EXACT TRACK OF UPPER LOW IS STILL VERY MUCH IN QUESTION...ANY MODEL SOLUTION WARRANTS POPS FOR THE FORECAST AREA SATURDAY. WILL INDICATE LIKELY POPS FOR MOUNTAINS AND CHANCE FOR ALL OTHER ZONES. ALSO...SHOULD BE ENOUGH INSTABILITY TO WARRANT THE MENTION OF THUNDER SATURDAY. FOR SUNDAY/MONDAY...ALL MODELS MOVE THE UPPER LOW EASTWARD...SO EXPECT DRY CONDITIONS AND WARMING TEMPS. FOR DAYS 6/7...UPPER RIDGE BUILDS OVER AREA WITH DRY CONDITIONS AND WARMER TEMPS.

LAX 000. THOMPSON.

.LAX...SMALL CRAFT ADVISORY...SEE LAXCWFLAX.



BASED ON ACARS DATA PLAN TO RAISE THIS AFTERNOON/S HIGHS SLIGHTLY IN THE CENTRAL AND NORTH PART. ALSO WILL ADJUST WIND TO BECOMING SW THIS AFTERNOON BASED ON CURRENT OBS AND RUC.

FCSTID = 5 CAE 61 41 59 33 / 5 10 10 5 AGS 64 40 61 31 / 5 20 20 10 SSC 60 41 59 33 / 5 10 10 5 OGB 64 40 61 32 / 5 20 20 10

.CAE... GA...NONE. SC...NONE.

RJL