Forecast Discussions mentioning ACARS, received at FSL on 06/23/99

...SYNOPSIS... A WEAK UPPER TROUGH WILL CONTINUE WEST OF BAJA CALIFORNIA THROUGH WEDNESDAY MORNING. THIS WILL LOWER THE MARINE LAYER. THE MARINE LAYER WILL DEEPEN ON WEDNESDAY NIGHT AND THURSDAY AS ONSHORE FLOW INCREASES. OVER THE MOUNTAINS AND DESERTS...HIGH PRESSURE WILL CONTINUE WITH FAIR SKIES AND TEMPERATURES SLOWLY WARMING.

...DISCUSSION... SEVERAL EQUIPMENT PROBLEMS LOCAL AND UPSTREAM HAMPERED RECEIPT OF OBSERVATIONS AND MODEL GUIDANCE PAST 24 HOURS...AND KNKX RAOB WILL NOT BE AVAILABLE FOR 23/12Z RUN EITHER. MAIN REASON FOR SUDDEN CLEARING ALONG COASTS AND INLAND VALLEYS TODAY WAS FLOW WENT OFFSHORE IN RESPONSE TO MID/UPPER TROUGH DIGGING TO THE SOUTHWEST OF NWSO SGX COUNTY WARNING AREA. LATEST PROFILERS AND ACARS DATA SHOW MARINE LAYER HAS SHRUNK TO AROUND 1500 FEET. LATEST NGM AND CONTINUE EAST TO SOUTHEAST FLOW IN THE 1000-850 MB LAYER THROUGH WEDNESDAY...SO DO NOT EXPECT LOW CLOUDS TO GET MUCH BEYOND IMMEDIATE COAST TONIGHT... SO WILL MAKE SOME DOWNWARD ADJUSTMENTS TO INLAND VALLEY CLOUD COVER AND MINIMUM TEMPERATURES. THICKNESS INCREASES OVER THE MOUNTAINS AND DESERTS AROUND 30 METERS TONIGHT...CURRENTLY HAVE 6 TO 10 DEGREES FAHRENHEIT WARMING FORECAST SO WILL CUT THAT IN HALF. MOISTURE SURGE UP THE GULF INTO SOUTHWEST ARIZONA NOW...MODELS BRING LIMITED AMOUNTS OF THIS UP THROUGH SE CALIFORNIA. WILL ADJUST CLOUD COVER FOR EASTERN MOUNTAINS AND DESERTS TO INCLUDE AFTERNOON CUMULUS.

BACK ALONG THE COAST...SOUTHERN HEMISPHERE FETCH CHARTS FROM JUNE 11-13 SHOW ORIGIN OF CURRENT SOUTH SWELL FROM TWO AREAS...ONE OFF S COAST OF CHILE AND THE OTHER S OF NEW ZEALAND. RESULT SHOULD BE ABOVE NORMAL SURF THROUGH WEDNESDAY ALONG SOUTH AND SOUTHWEST FACING BEACHES...STATEMENT DUE OUT SHORTLY...ZONES TO FOLLOW. SAN 0000

.SAN...ABOVE NORMAL SURF...SEE LAXMWSSAN.

BALFOUR

WILL RELEASE EVENING UPDATE TO TWEAK MAINLY VALLEY HIGH TEMPS DOWN A FEW DEGREES. AGREE WIH PREVIOUS SHIFT ON WARMING TREND...HOWEVER ONLY 3 DEGREES WARMING EXPECTED FOR WEDNESDAY.

FOR THE NEXT 12 HOURS...FOG PRODUCT SAT PIX SHOWING THE LOW CLOUDS ADVANCING TOWARD THE COAST FOR THE UMPTEENTH TIME THIS YEAR. VBG SOUNDING SHOWING THE MARINE LAYER STILL AT 2500 FEET DEEP. SOME DIFFERENCES TONIGHT ARE SHOWN ON THE USC PROFILER AND ACARS DATA...THE MARINE LAYER HAS SHRUNK DOWN TO AROUND 1700 FEET ALONG THE LA COUNTY COAST. STILL BELIEVE THAT SOME LOW CLOUDS WILL MAKE IT INTO THE VALLEYS TONIGHT TO PREVENT ANYTHING MORE THAN MODEST GAINS IN MAX TEMPS...BUT THE MIDNIGHT SHIFT WILL NEED TO MONITOR THE LATEST CONDITION OF THE MARINE LAYER.

FOR THE 12 TO 48 HOUR PERIOD...A TROF WILL PUSH INTO THE PAC NW WED NIGHT AND THU TO LOWER HEIGHTS AND INCREASE ONSHORE FLOW WHICH IS CURRENTLY ON THE WEAK TO MODERATE SIDE. THIS WILL INITIATE COOLING ON THU...WIPING OUT ANY GAINS MADE ON WED. THE COOLING CONTINUES INTO FRI BEFORE MEDIUM RANGE MODELS BEGIN TO DIVERGE ON SOLUTIONS FOR THE THE EXTENDED. WISH _HE " " WORKED ON _HIS KEYBOARD...

FOR THE EXTENDED...THE MRF SHOWS THE TROF IN THE PAC NW PROGRESSING EAST AND MOST OTHER MODELS SHOW THE TROF REMAINING THRU 5 DAYS. MIDNIGHT SHIFT MAY WANT TO TONE DOWN THE CURRENT WARMING TREND IN THE STATE FORECAST...GIVEN THE ISOLATED NATURE OF THE MRF SOLUTION.

LAX 000. SWEET.

.LAX...NONE.

LATEST SATELLITE SHOWS SUNNY SKIES ACROSS MOST OF THE DISTRICT WITH STRATUS/FOG HANGING TOUGH NEAR SOME COASTAL AREAS. ACARS DATA INDICATES MARINE LAYER STILL AROUND 2000-2500 FEET.

12Z MODELS ONCE AGAIN IN GOOD AGREEMENT WITH SYNOPTIC PATTERN ACROSS THE DISTRICT THROUGH THURSDAY. WEAK UPPER RIDGE WILL BUILD OVER THE AREA TONIGHT...WHICH WILL HELP SHRINK MARINE LAYER SOMEWHAT. HOWEVER MARINE LAYER WILL STILL BE DEEP ENOUGH FOR WIDESPREAD STRATUS/FOG FOR COASTAL AREAS FROM SAN LUIS OBISPO TO LOS ANGELES...WITH AREAS OF STRATUS/FOG OVER THE VENTURA/LA VALLEYS TONIGHT. INTERIOR VALLEYS OF SLO COUNTY SHOULD REMAIN CLEAR WITH SHALLOWER MARINE LAYER. EXPECT QUICK BURNOFF WEDNESDAY MORNING AS ONSHORE GRADIENTS DO NOT SHOW ANY INCREASE. FOR WEDNESDAY NIGHT AND THURSDAY...H5 HEIGHTS LOWER IN RESPONSE TO DEVELOPING TROUGH OVER THE PACIFIC NORTHWEST. ALSO... ONSHORE FLOW WILL STRENGTHEN ON THURSDAY IN RESPONSE TO DEVELOPING TROUGH. THEREFORE...WILL EXPECT SLIGHTLY DEEPER MARINE LAYER WEDNESDAY NIGHT...PUSHING SOME STRATUS/FOG INTO SALINAS VALLEY...WITH A SLIGHTLY SLOWER BURNOFF THURSDAY. FOR MOUNTAIN/DESERTS...SKIES SHOULD REMAIN MOSTLY CLEAR THROUGH THURSDAY.

AS FOR TEMPS...MODELS INDICATE SOME THICKNESS INCREASES AND BOUNDARY LAYER WARMING ON WEDNESDAY. COMBINED WITH SHALLOWER MARINE LAYER... TEMPS WEDNESDAY SHOULD BE SEVERAL DEGREES WARMER...ESPECIALLY INLAND. ON THURSDAY...MODELS INDICATE LOWERING THICKNESSES WHICH WILL TRANSLATE INTO SLIGHTLY COOLER TEMPS FOR ALL AREAS.

LAX 000. THOMPSON.

.LAX...NONE.

...SYNOPSIS...

ONSHORE FLOW AND THE MARINE LAYER WILL CONTINUE NIGHT AND MORNING LOW CLOUDS AND FOG WEST OF THE MOUNTAINS. OTHERWISE...HIGH PRESSURE WILL KEEP THE WEATHER FAIR. A LITTLE WARMER WEDNESDAY THEN SLIGHTLY COOLER THURSDAY AS THE HIGH WEAKENS.

...DISCUSSION...

EDDY THIS AM AND DEEPER MARINE LAYER WITH LOW CLOUDS/LOCAL FOG INTO INLAND EMPIRE. NO 12Z NKX SOUNDING BUT ACARS/PIREPS INDICATE MARINE LAYER WAS ABOUT 2000-2500 FT DEEP. HOWEVER...LOW CLOUDS BURNED OFF QUICKER AND MORE COMPLETELY THAN YESTERDAY WITH WEAK NE WIND ALOFT AND OFFSHORE TREND. GRADIENTS LESS THAN 5 MB ONSHORE SAN-IPL. STRATUS STILL REMAINS RATHER EXTENSIVE OFFSHORE.

PROBLEMS WITH AVN BEYOND 48 HOURS TODAY. MODELS TAKE STRONG UPPER HI OVER ERN PAC AND FLATTEN IT AS UPPER TROF MOVES INTO PAC NW WED/THU. THIS WILL RESULT IN SLIGHT INCREASE IN LOCAL HEIGHTS/ THICKNESS/850 MB TEMPS INTO WED THEN OR SLIGHT DECREASE LATE WED/THU. THE WEAKER ONSHORE GRADIENTS WILL CONTINUE INTO WED AND SHOULD HAVE SHALLOWER MARINE LAYER. SO EXPECT MARINE LESS INLAND PENETRATION AND EVEN BETTER/EARLIER CLEARING WITH NO EDDY SINCE CYCLONIC FLOW AT 850 MB HAS WEAKENED. SMALL DECREASE IN HEIGHTS/ THICKNESS AND A LITTLE STRONGER ONSHORE FLOW THU FOR SOME DEEPENING OF MARINE LAYER. A LITTLE WARMER IN ALL AREAS WED THEN SLIGHT COOLER THU...MAINLY W OF MOUNTAINS. SOME SE FLOW ALOFT BUT NO SIGNIFICANT MOISTURE INDICATED...HOWEVER WILL HAVE TO WATCH.

LONGER RANGE PROGS NOT IN BEST OF AGREEMENT WITH MRF/UKMET SHOWING STRONG UPPER HI TO SE WITH TROF NEAR PAC NW. ECMF INDICATES STRONGER TROF OVER W COAST. STILL LOOKS LIKE WARMING TREND EARLY NEXT WEEK. NOT FAVORABLE PATTERN TO GET MOISTURE FROM S BUT COULD GET ENOUGH FOR SOME AFTERNOON CLOUDS IN MOUNTAINS.

SAN 0000

.SAN...NONE.

ATKIN