Forecast Discussions mentioning ACARS, received at FSL on 06/17/99

EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
AFDSAN 840 PM PDT WED JUN 16 1999

...SYNOPSIS... WEAK HIGH PRESSURE WILL BUILD ACROSS SOUTHERN CALIFORNIA THROUGH FRIDAY WITH WARM TEMPERATURES AWAY FROM THE COAST. CLOSER TO THE COAST...NIGHT AND MORNING LOW CLOUDS AND FOG WILL CLEAR TO NEAR THE BEACHES EACH AFTERNOON. ...DISCUSSION... CURRENT FORECAST PACKAGE LOOKS ON TARGET WITH ONLY MINOR ADJUSTMENTS NEEDED AT MOST. HIGH TEMPERATURES FOR HEMET...MIRAMAR...RANCHO BERNARDO...FREMONT CANYON...AND BORREGO MAY BE SLIGHTLY TOO LOW BASED ON HIGH TEMPERATURES OBSERVED TODAY AND EXPECTED GRADUAL WARMING TREND THU AND FRI...BUT NOT ENOUGH TO WARRANT AN UPDATE AT THIS TIME...SO WL LEAVE FOR NEXT ROUTINE ISSUANCE ON THE MID SHIFT.

ACARS SOUNDINGS THIS EVENING SHOW THE MARINE LYR DEPTH RANGING FM 1500 TO 2000 FT ALG THE CST...TO 2000 TO 2500 FEET IN THE VLYS OF THE INLAND EMPIRE. THIS IS SUFFICIENTLY DEEP TO ALLOW STRATUS TO RETURN LATE TONIGHT TO THE INLAND VLYS. WK EDDY FORECAST TO FORM OVERNIGHT BY COAMPS AND RUC SHOULD DECAY FASTER THU AS SYNOPTIC SUPPORT FOR THE EDDY WEAKENS. SYNOPTIC SUPPORT FOR AN EDDY IS WEAKER THU NIGHT WITH NEITHER COAMPS OR RUC DEVELOPING AN EDDY.

HEIGHTS ALF TO INCR SOME THE NEXT 24 HOURS WITH MINOR CHANGES FOR FRI. THIS SHOULD RESULT IN SOME DECR IN MARINE LYR DEPTH THU TO AROUND 1500 OR A LTL LWR WITH A MARINE LYR DEPTH FRI OF 1000 TO 1500 FT. THUS...FOR THU NIGHT AND FRI NIGHT...LOW CLOUDS WL INCRGLY BE CONFINED CLOSER TO THE CST. WITH THE STRONG INVERSION AND ONLY WK ONSHR GRADIENTS...LOW CLOUDS AND FOG WL CLEAR BACK TO THE CST EARLIER...BUT REMAIN NR THE BEACHES EACH AFTERNOON.

WEEKEND...AVN SHOWS AN UPR RDG BECOMING ESTABLISHED OVR THE SW CNTRD NR THE FOUR CORNERS WITH SHALLOW MID LVL MSTR RETURNING TO ERN SXNS OF SRN CA. THIS SHOULD BE AT LEAST SUFFICIENT FOR AFTERNOON CLOUDS TO DEVELOP OVR THE MTNS FROM THE SBD MTNS S SAT AND SUN. ENOUGH MONSOONAL MSTR MAY ARRIVE BY SUN FOR A FEW AFTERNOON THUNDERSTORMS SRN MTNS AND ERN DESERTS OF SRN CA.

IN GENERAL THRU THE WEEKEND...SEASONAL WEATHER WITH WARM TEMPERATURES AWAY FM THE CST WITH LOW CLOUDS LINGERING NR THE BEACHES.

SAN 0000

.SAN...NONE.

MARTIN

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
AFDLOX 915 AM PDT THU JUN 17 1999

NO UPDATES EXPECTED...WILL LOWER AFTN WINDS IN ANTELOPE VALLEY IN AFTN PACKAGE ONCE ALL MODELS ARE IN.

FOR THE NEXT 12 HOURS...PRES GRADS SIMILAR TO YESTERDAY...SLIGHTLY WEAKER ONSHORE FLOW. PROFILER DATA SHOWS LITTLE CHANGE IN THE MARINE LAYER HEIGHT. ACARS DATA INDICATES A SLIGHTLY DEEPER MARINE LAYER WITHIN THE LAX VICINITY...NEAREST AN EDDY IN THE COASTAL WATERS. VISBL PIX SHOW LOW CLOUDS IN CLEARING MODE AS PER CURRENT FORECAST... SO WHY CHANGE A GOOD THING.

FOR THE 12 TO 48 HOUR PERIOD...12Z ETA IN AGREEMENT WITH 00Z MODELS IN TREND OF RISING HEIGHTS OVR CWA ALONG WITH A SLOW INCREASE IN 850 MB TEMPS. THESE TWO FACTORS WILL CONSPIRE TO BRING SLIGHTLY WARMER TEMPS TO THE CWA THRU SAT. LOW CLOUDS TOPPING OUT AT 020 THIS AM WILL GET SQUASHED A LITTLE BY FRI. RISING HEIGHTS OVR CWA ASSOCIATED WITH AMPLIFYING RIDGE OVER SOUTHERN INTERMOUNTAIN REGION. THIS RIDGE WILL TURN THE MID AND UPPER LEVEL WINDS AROUND TO THE SOUTH AND SOUTHEAST OVER THE WEEKEND. ACTUALLY...MID LEVEL SOUTHERLIES ALREADY SHOWING UP AT MIRAMAR THIS AM.

EXTENDED...MID AND UPPER LEVEL SOUTHERLIES EXPECTED TO TRANSPORT SOME MID LEVEL MOISTURE INTO MOUNTAINS FRI FOR A FEW AFTN BUILDUPS AND OVR THE WEEKEND FOR A CHANCE OF TSRA. CSTL AND VALLEY TEMPS WILL CONTINUE A SLOW CLIMB DUE TO RISING HEIGHTS AND A SHALLOW MARINE LAYER. MTN TEMPS MAY FALL A COUPLE OF DEGREES WITH INCREASED RH.

LAX 000. SWEET.

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