Forecast Discussions mentioning ACARS, received at FSL on 06/22/99

LATEST SATELLITE SHOWS THIN VEIL OF HIGH CLOUDS OVER THE DISTRICT... WITH STRATUS/FOG FINALLY CLEARING TO THE COAST. STRONGER ONSHORE FLOW AND DEEPER MARINE ARE THE CULPRITS FOR SLOWER CLEARING TODAY. LATEST ACARS SOUNDINGS INDICATE MARINE LAYER HAS DEEPENED...WITH THE BASE OF THE INVERSION AROUND 2000 TO 2500 FEET. IN SHORT TERM...EXPECT LOW CLOUDS AND FOG TO LINGER NEAR THE COAST THIS AFTERNOON...THEN PUSH INLAND THIS EVENING.

MODELS...ONCE AGAIN...IN GOOD AGREEMENT WITH QUIET SYNOPTIC PATTERN THE NEXT COUPLE OF DAYS. WEAK UPPER RIDGE WILL DEVELOP OVER THE AREA TUESDAY AND WEDNESDAY. WITH BUILDING UPPER RIDGE...SLIGHT INCREASE IN HEIGHTS WILL HELP SQUASH THE MARINE LAYER SLIGHTLY. HOWEVER...WITH ONSHORE FLOW PROGGED TO CONTINUE THE NEXT COUPLE OF DAYS...MARINE LAYER WILL BE DEEP ENOUGH TO BRING STRATUS/FOG INTO VENTURA AND LOS ANGELES VALLEYS...AS WELL AS SOME PATCHY STRATUS/FOG IN THE SALINAS VALLEY TUESDAY/WEDNESDAY MORNING. FORTUNATELY...ONSHORE FLOW WILL BE WEAKER TUESDAY AND WEDNESDAY AFTERNOONS...ALLOWING FOR QUICKER CLEARING OF THE MARINE LAYER. FOR MOUNTAINS/DESERTS...UPPER RIDGE WILL KEEP SKIES MOSTLY CLEAR.

TEMPS WILL SHOW ONLY MINOR INCREASES THE NEXT COUPLE OF DAYS. WITH SLIGHTLY SHALLOWER MARINE LAYER...WEAKER ONSHORE FLOW/BETTER CLEARING AND SLIGHT BOUNDARY LAYER WARMING...TUESDAY HIGHS WILL BE A FEW DEGREES WARMER THAN TODAY. FOR WEDNESDAY...TEMPS MAY CLIMB ANOTHER DEGREE OR TWO AS MODELS INDICATE SOME SLIGHT INCREASE IN THICKNESSES AND 850 TEMPS.

LAX 0000. THOMPSON.

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

...SYNOPSIS... ONSHORE FLOW AND THE MARINE LAYER WILL CONTINUE NIGHT AND MORNING LOW CLOUDS AND FOG WEST OF THE MOUNTAINS. LOCALLY BREEZY IN THE MOUNTAINS AND DESERT AT TIMES. OTHERWISE...HIGH PRESSURE WILL KEEP THE WEATHER FAIR WITH A LITTLE WARMER DAYS.

...DISCUSSION... THE UPPER TROUGH NOW PASSING OVER AREA INCREASED THE STRENGTH OF THE COASTAL EDDY AND DEPTH OF THE MARINE LAYER...IN ADDITION TO BRINGING HIGH CLOUDS ACROSS MOUNTAINS AND DESERTS. RESULT WAS ABOUT 8 TO 13 DEGREES FAHRENHEIT COOLING ACROSS INLAND AREAS THIS AFTERNOON... WHILE ALONG THE COAST THE ONSHORE FLOW AND LOW CLOUDS KEPT TEMPERATURES IN THE MID 60S...ROUGHLY THE VALUE OF THE SEA SURFACE TEMPERATURE. UPPER AIR EQUIPMENT FAILURE AT KNKX WILL CONTINUE THROUGH THE 22/12Z RUN. NAVY PROFILERS AND ACARS DATA INDICATE THE DEPTH OF THE MARINE LAYER INCREASED TO AROUND 2000 FEET THIS AFTERNOON. UPDATED THE FORECASTS AT 9 PM TO LOWER TEMPERATURES AS UNLIKELY TO RECOVER MUCH MORE THAN A FEW DEGREES EACH DAY WITH THICKNESS VALUES RISING ONLY 10-20 METERS PER DAY.

THE OTHER FORECAST PROBLEM WORTH NOTING IS THE CONTINUED POSSIBILITY OF A MOISTURE SURGE UP THE GULF THE NEXT SEVERAL DAYS. THE LATEST ETA AND NGM MODELS TAKE A PORTION OF THE UPPER TROUGH TO THE SOUTHWEST OF THE AREA AND LEAVE IT QUASI-STATIONARY. THIS RESULTS IN INTERMITTENT SOUTH TO SOUTHEAST FLOW IN THE LOWER 5000 FEET ACROSS THE UPPER GULF OF CALIFORNIA/SOUTHEAST CALIFORNIA THE NEXT TWO DAYS. THIS IS CONSISTENT WITH WHAT THE MRF/AVN MODELS WERE ADVERTISING SEVERAL RUNS AGO FOR THE SAME TIME PERIOD. HOWEVER DURING THE MAXIMUM HEATING PERIOD...18Z-06Z...EACH DAY THE FLOW SWITCHES TO SOUTHWEST ACROSS THE DESERTS...RESULTING IN MOISTURE SURGE REMAINING MORE OR LESS DUE NORTH UP THE LOWER COLORADO RIVER VALLEY. MODEL DERIVED SOUNDINGS OVER COACHELLA VALLEY/SAN DIEGO COUNTY DESERTS INDICATE ONLY ISOLATED TO SCATTERED HIGH BASED CUMULUS...SO THE MOSTLY SUNNY FORECAST LOOKS OKAY FOR NOW.

SAN 0000

.SAN...NONE.

BALFOUR

...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 WITH A LITTLE WARMER DAYS.

...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 ABOUT 2000-2500 FT DEEP. HOWEVER...LOW CLOUDS BURNING OFF QUICKER THAN YESTERDAY WITH OFFSHORE TREND AND GRADIENTS LESS THAN 5 MB ONSHORE SAN-IPL.

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 LITTLE CHANGE OR SLIGHT DECREASE LATE WED/THU. MUCH WEAKER ONSHORE GRADIENTS TODAY THEN LITTLE CHANGE OR SLIGHT INCREASE WED. EXPECT MARINE LAYER DEPTH TO DECREASE FOR LESS INLAND PENETRATION AND BETTER/ EARLIER CLEARING WITH WEAKER...IF ANY...EDDY NEXT COUPLE OF DAYS AS CYCLONIC FLOW AT 850 MB WEAKENS. A LITTLE WARMER IN ALL AREAS TODAY THEN SLIGHT WARMING OR LITTLE CHANGE WED. SOME SE FLOW ALOFT BUT NO SIGNIFICANT MOISTURE INDICATED SO OTHER THAN STRATUS WILL HAVE MOSTLY CLEAR SKIES.

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 000

.SAN...NONE.

ATKIN