Forecast Discussions mentioning ACARS, received at FSL on 06/30/99

LATEST FOG PRODUCT SHOWS LOW CLOUDS MOVING SLIGHTLY INLAND OVER THE CENTRAL COAST AND IS MAINLY ALONG THE IMMEDIATE COAST ELSEWHERE EXCEPT LAX/LGB HARBOR AREA WHERE SKIES STILL CLEAR. LATEST PROFILER/ACARS SOUNDINGS SHOW MARINE INVERSION QUITE LOW...GENERALLY 600 FT TO NEAR 1K FEET. CLOUDS COMING IN UNDER 1K FEET BUT NO DENSE FOG REPORTED YET. A WEAK EDDY DEVELOPED LAST NIGHT...BUT DIFFICULT TO SAY IF ONE WILL FORM TONIGHT. W TO E ONSHORE GRADIENTS STILL FAIRLY STRONG (LAX-DAG +6.5 MB AT 03Z). HOWEVER...OFFSHORE WINDS WEAK (15 KT OR LESS) SO ANY EDDY THAT DOES GET GOING SHOULD BE VERY WEAK. AT THIS TIME...IT APPEARS LOW CLOUDS WILL GET LOWER OVENIGHT WITH DENSE FOG DEVELOPING IN PLACES. LOW CLOUDS SHOULD STAY OUT OF INLAND VALLEYS TONIGHT.

00Z ETA/NGM INDICATE W TO E ELONGATED UPPER RIDGE TO LINGER FROM SRN CA TO WELL OFF W COAST THRU THU. NGM SLIGHTLY HIER WITH HEIGHTS/ THICKNESSES THAN ETA...AND IN FACT GIVES LAX A THICKNESS OF 590 DM AT 30 HOURS AND 48 HOURS! THE NGM ALSO GIVES A HINT OF THE THERMAL TROF GETTING CLOSER TO THE COAST AT TIMES MORE SO THAN THE ETA. THIS COULD HAVE SOME IMPACT ON HAVING EVEN HOTTER HI TEMPS THAN IS CURRENTLY FORECAST IF THIS VERIFIES. AVN MAY SHED SOME LIGHT ON THIS. FOR NOW AGREE WITH HI TEMPS AS THAY STAND EXCEPT PASO ROBLES HI TEMPS SHOULD PROBABLY BE BOOSTED A FEW DEGREES SINCE HI THERE TODAY WAS 105. AT ANY RATE...OTHER THAN PASO ROBLES HI TEMPS...CURRENT FORECASTS LOOK REASONABLE...THEREFORE NO FORECAST UPDATES PLANNED THIS EVENING.

EXTENDED FORECAST...VERY WARM AGAIN FRI...THEN SOME W COAST TROFFINESS DEVELOPS WHICH WILL LOWER TEMPS SLIGHTLY SAT AND SUN. ATMOS TO REMAIN DRY WITH A SWLY FLOW ALOFT SO NO DIURNAL CONVECTION EXPECTED ANYWHERE. LOOKS LIKE FAIRLY TYPICAL WEATHER FOR EARLY JULY OVER SOCAL WITH DRY AND WARM TO HOT WEATHER INLAND....AND STILL COOLER AT THE BEACHES.

LAX 0000. SIRARD.

.LAX...NONE.

SAT PIX AND SFC OBS INDICATE LOW CLOUDS HAVE SPREAD INTO MST CSTL AREAS EARLY THIS MORNING...BUT HAVE YET TO INFILTRATE ACARS SOUNDINGS AND PROFILER DATA SUGGESTS THAT THE MARINE LYR DEPTH IS BETWEEN 1000 AND 1300 FEET...MORE SHALLOW THAN 24 HRS AGO. MARINE LYR IS PROBABLY STILL DEEP ENOUGH TO ALLOW AT LEAST PATCHY LOW CLDS/FOG TO PUSH INTO LOWER VLY LOCATIONS...ESPECIALLY GIVEN THAT ONSHR GRADS REMAIN MDT. THE FOG WAS ALREADY LCLLY DENSE ACRS PARTS OF WRN SBA COUNTY AND WITH MARINE INVERSION CONTG TO LOWER...BLV DENSE FOG WL BECOME MORE WDSPRD. WL ISSUE A DENSE FOG ADVISORY AT LEAST FOR CSTL SXNS OF SLO AND WRN SBA COUNTIES THIS MORNING.

FLAT BUT STG UPR RIDGE WAS NOSING INTO SRN CA FROM THE PAC... AND ASSOCD SUBSIDENCE HAS CAUSED MARINE LYR TO BECOME INCRGLY SHALLOW. PROFILER DATA AND SFC OBS FROM THE MORE ELEVATED REPORTING STATION SHOW CONSIDERABLE WARMING HAS OCCURRED ABOVE 1500 FEET DURING THE PAST 24 HRS. INLAND AREAS WILL CONT TO SLOWLY WARM EACH OF THE NEXT TWO DAYS DUE TO RISING THICKNESSES...AND INCRSG H85 AND BOUNDARY LYR TEMPS. MORE SUBSTANTIAL WARMING WILL OCCUR IN THE VLYS ONCE THE MARINE INVERSION LOWERS ENOUGH TO CAUSE A SHARP REDUCTION OF THE MARINE INFLUENCE IN THE VLYS. THIS WILL PROBABLY OCCUR TODAY...ALTHOUGH MAY WAIT UNTIL WED... ESPECIALLY IN LOWER VLY LOCATIONS. ON THE CSTL PLAIN...DECENT ONSHR GRADS WILL TEMPER WARMING SOMEWHAT...ESPECIALLY NEAR THE CST WHERE TEMPS SHOULD CHG LTL OF THE NEXT COUPLE OF DAYS. STRENGTHENING AND LOWERING INVERSION COULD KEEP CLOUDS FAIRLY STUBBORN IN IMDT CSTL AREAS WELL INTO THE AFTERNOON HOURS TODAY AND WED.

LOW LVL OUTFLOW FROM A LARGE TSTORM COMPLEX WHICH DEVELOPED ACRS AZ LAST EVENING HAS PUSHED LOW LVL MSTR WWD INTO THE SRN CA DSRTS AND DEW POINTS HAVE RISEN SHARPLY...INTO THE LOWER 70S. WATER VAPOR INDICATES A WWD DRIFT OF THE UPR LVL MSTR ACRS XTRM SRN CA ATTM. HOWEVER.,.ALL MODELS MAINTAIN AT LEAST WK WLY TO NWLY FLOW ALF OVR THE FCST AREA WHICH SHOULD KEEP MSTR SUPPRESSED TO THE S OF THE FCST AREA.

FOR THE EXTENDED...UPR RIDGE WL HOLD STRONG THROUGH THU WITH HIGH HGTS AND ABOVE NORMAL TEMPS CONTG. AS UPR TROUGH DEVELOPS ACRS THE PAC NW FRI AND SAT HEIGHTS ACRS SRN CA WILL SLWOLY LOWER AND XPCT SOME GRADUAL COOLING BY SAT.

LAX 000. BRUNO.

.LAX...DENSE FOG ADVISORY...SEE LAXNPWLAX.

LOW CLOUDS HAVE SPRD INTO MOST CSTL AREAS EARLY THIS A.M.. ACARS SOUNDINGS AND PROFILER DATA INDICATE BASE OF MARINE INVERSION WAS RUNNING BETWEEN 1000 AND 1200 FT...VERY SIMILAR TO 24 HRS AGO. ONCE AGAIN...MARINE LYR SHOULD BE JUST DEEP ENOUGH TO ALLOW AT LEAST PTCHY LOW CLDS/FOG TO PUSH INTO LOWER VLY LOCATIONS SINCE ONSHR GRADS REMAIN MDT. AS WAS THE CASE TUE A.M....FOG WAS BECOMING LCLLY DENSE ACRS PARTS OF WRN SBA AND SLO COUNTIES. WITH DENSE FOG LIKELY TO BECOME MORE WDSPRD...WL ISSUE DENSE FOG ADVISORIES WITH THE MORNING FCST FOR CSTL SXNS OF SLO AND SBA COUNTIES. WIND ANALYSIS HINTS AT WK EDDY CRCLN ACRS INNER CSTL WATERS. 03Z ETA SHOWS THIS AS WELL FOR EARLY THIS A.M.... THEN AGAIN LATE TONIGHT AND THU A.M.. WITH SUCH HIGH HGTS OVER THE AREA...SUCH A WEAK CRCLN SHOULD BE UNABLE TO DEEPEN MARINE LYR...BUT MAY WELL PREVENT IT FROM BECOMING MUCH MORE SHALLOW...THUS KEEPING ST PATTERN QUITE SIMILAR TODAY AND THU.

MODELS AGREE THAT OVERALL WEATHER PATTERN WILL CHG LTL THROUGH THU WITH UPR HIGH PERSISTING ACRS THE FCST AREA AND MDT ONSHR FLOW CONTG. WITH SOME SMALL RISES IN THICKNESSES AND H85 TEMPS BETWEEN TUE AND TODAY...XPCT A FEW DEGS OF WARMING IN MOST AREAS TODAY. THE XCPTN WL BE THE CSTL PLAIN WITHIN A FEW MILES OF THE OCEAN WHERE COOLING ONSHR FLOW WL ALLOW FOR LTL CHG. MDLS DIVERGE A BIT ON THU...WITH AVN SHOWING SOME SLGT LOWERING OF HGTS/H85 TEMPS...NGM SHOWING SOME WARMING...AND ETA SHOWING LTL CHG. SINCE ANY MODEL SHOWS ONLY SLGT VARIATION FROM TODAY...THE COMPROMISE SOLN OF THE ETA IS ACCEPTED. WITH LTL CHG IN ONSHR GRADS AND MARINE LYR DEPTH AND ST PATTERN XPCTD TO BE SIMILAR... XPCT THU TO BE NEARLY IDENTICAL TO TODAY.

FOR THE EXTENDED...MODELS CONT TO TROUGH DVLPMNT ACRS THE PAC NW BEGINNING FRI...THEN DEEPENING SAT AND SUN...BUT ALL MED RANGE MODELS HAVE BACKED OFF A BIT WITH THEIR HGT FALLS ACRS SRN CA. ALTHOUGH STG UPR HIGH OVER SRN CA IS STILL FCST TO BE RELACED BY WK TROUGHINESS... IT LOOKS LIKE THE MAGNITUDE OF HGT/THICKNESS FALLS WL BE SMALL ENOUGH TO PRECLUDE ANY MAJOR COOLING ACRS MOST OF THE AREA. THE AREAS MOST LIKELY TO SEE SIGNIFICANT COOLING ARE THE VALLEYS...BUT THAT IS ONLY IF SUFFICIENT MARINE DEEPENING OCCURS.

LAX 000. BRUNO.

.LAX...DENSE FOG ADVISORY...SEE LAXNPWLAX.