Forecast Discussions mentioning "ACARS", "MDCRS", or "AIRCRAFT" received at FSL on 03/12/02

.SYNOPSIS...A DEVELOPING MARINE LAYER WILL CAUSE AREAS OF NIGHT AND MORNING COASTAL LOW CLOUDS AND FOG...INCREASING TUESDAY NIGHT. OTHERWISE...WEAKENING HIGH PRESSURE ALOFT WILL KEEP THE WEATHER FAIR THROUGH TUESDAY. UPPER LEVEL LOW PRESSURE WILL BRING PARTLY CLOUDY... COOLER AND LOCALLY WINDY CONDITIONS DURING THE SECOND HALF OF THE WEEK.

.DISCUSSION...PATCHY LOW CLOUDS WERE FORMING NEAR THE SAN DIEGO COUNTY COAST...OTHERWISE SKIES WERE MOSTLY CLEAR. ONSHORE PRESSURE GRADIENTS HAD ACTUALLY WEAKENED SOMEWHAT IN THE PAST 24 HOURS...THOUGH DENSITY GRADIENTS WERE GENERALLY MORE ONSHORE. THE INVERSION AGAIN IS QUITE SHALLOW...WITH ACARS INDICATING IT BELOW 1000 FEET. SO...THE LOW CLOUDS AND FOG SHOULD BE CONFINED MOSTLY TO COASTAL AREAS. 00Z MSO/18Z WORKSTATION-ETA BACKED OFF OF AN EDDY SOLUTION BY ABOUT A DAY VERSUS THE SOLUTIONS 24 HOURS BEFORE...AND EVEN THE EDDY FOR TUESDAY NIGHT WILL NOT BE EXCEEDINGLY STRONG. SO...TUESDAY LOOKS LIKE ANOTHER MILD DAY WEST OF THE MTNS BEFORE WE GET THE COOLING DUE TO THE MUCH STRONGER ONSHORE FLOW AND LOWER HEIGHTS WED. IVORY'S WIND PROGRAM AND NGM/AVN MOS INDICATE RATHER STRONG WINDS FOR WED OVER THE MTNS/DESERTS REGIONWIDE WITH THE HIGHEST MOS WIND BEING THE AVN LANCASTER WIND OF 39 KTS WED PM...SO OUR UPPER DESERTS WILL LIKELY BE NOT FAR BEHIND. THIS WILL BE DUE TO THE TIGHT GRADIENTS AT 700/500 MB SOUTH OF THE DEVELOPING TROUGH OVER THE PAC NW/N CAL...AND MOUNTAIN WAVES WILL BE ABLE TO DEVELOP...ESPECIALLY SINCE WE WILL NOT YET BE IN THE PVA COMING DOWN WITH THE SYSTEM TO THE NORTH WHICH WOULD OTHERWISE INHIBIT SOME OF THE MTN WAVE ACTION.

AS FOR ANY CHANCES OF RAIN THU...THE DYNAMICS LOOK GOOD...ESPECIALLY WITH THE MSO...BUT THE MOISTURE AMOUNTS LOOK TOO LOW. THE ONLY WAY WE WOULD GET RAIN GIVEN THE PRESENT MODEL GUIDANCE IS IF WE CAN HAVE AN EDDY CONTINUING THROUGH THU WITH A DEEP MOIST MARINE LAYER PROVIDING ENOUGH PRECIPITABLE WATER WHEN THE UPLIFTING COMES. THE LOW-LEVEL FLOW LOOKS A BIT TOO NORTHERLY FOR THAT NOW...BUT IF THE VORT MAX SAGS A BIT FURTHER WEST/SW AND THE OVER-WATER TRAJECTORY IS BETTER DUE TO MORE W FLOW...WE COULD GET RAIN. SINCE THERE ARE A LOT OF TOUGH QUESTIONS TO BE ANSWERED RIGHT BEFORE IT CAN RAIN...I WILL KEEP THE THU PERIOD DRY. HOWEVER...FRI/SAT IS NOT OUT OF THE QUESTION FOR PRECIP AS SECONDARY VORT MAXES COULD DRIFT DOWN...AND INSTABILITY BEHIND THAT 1ST THU VORT MAX COULD HELP TOO.

NO UPDATE WILL BE ISSUED TO THE ZONES THIS EVENING.

.SAN...NONE.

MAXWELL



.SYNOPSIS...DEVELOPING NORTHWEST FLOW WILL BRING GUSTY WINDS TO THE MOUNTAINS AND DESERTS AT TIMES WEDNESDAY INTO EARLY NEXT WEEK AS A DEEP TROUGH OF LOW PRESSURE DEVELOPS OVER THE INTERIOR WEST. A COASTAL EDDY WILL BRING INCREASING NIGHT AND MORNING LOW CLOUDS AND FOG TO THE COAST AND VALLEYS THROUGH WEDNESDAY MORNING. SIGNIFICANT COOLING WILL OCCUR IN INLAND AREAS WEDNESDAY AND THURSDAY...WITH A MODEST RECOVERY IN TEMPERATURES FOR THE WEEKEND.

.DISCUSSION...DEVELOPING NW FLOW WL BRING GUSTY WINDS TO THE MTNS AND DESERTS AT TIMES WED INTO EARLY NEXT WEEK AS A DEEP TROUGH OF LOW PRESSURE DEVELOPS OVR THE INTERIOR WEST.

MARINE LYR...ACARS SOUNDINGS EARLY MON EVENING SHOWED THE BASE OF THE MARINE INVERSION AROUND 500 FT WITH A TOP OF 1200 IN SOUTHERN LOS ANGELES COUNTY...WITH BOTH A FEW HUNDRED FEET DEEPER AT SAN. SURFACE OBSERVATIONS INDICATE THAT THE MARINE LYR MAY HAVE DEEPENED A LTL SINCE THEN. SURFACE REPORTS AND SATELLITE IMAGERY ARE CONSISTENT WITH THE EDDY SHOWN BY THE ETA. THE ETA ALLOWS THE EDDY TO DECAY THIS AFTERNOON...THEN REDEVELOP TONIGHT. THIS MORNING...LOW CLOUDS AND FOG COULD EXTEND LCLLY INTO THE LWR CSTL VLYS. GREATER DEEPENING OF THE MARINE LYR IS EXPECTED TONIGHT WITH CSTL STRATUS SPREADING INLAND OVERNIGHT TO ALL CST AND VLY AREAS. AS THE UPR TROUGH DEVELOPS OVR THE WEST WED AND THU...THIS WL BRING SIGNIFICANT COOLING ALF TO SRN CA. THIS SHOULD GREATLY ERODE OR ELIMINATE THE MARINE INVERSION BY WED NIGHT.

WINDS...FOR THE MTNS AND DESERTS...WINDS ARE EXPECTED TO INCR THIS AFTERNOON THROUGH TONIGHT WITH STRONGEST WINDS WED AND WED NIGHT INTO EARLY THU. WINDS COULD REACH ADV LVLS IN THE APPLE AND YUCCA VLYS DURING THIS PD AND POSSIBLY IN THE SBD MTNS. WINDS FOR THE APPLE AND YUCCA VLYS HAVE BEEN INCRD FOR WED TO JUST BLO WIND ADVISORY LVLS FOR NOW.

TEMPERATURES...HIGH TEMPERATURES TODAY IN THE INLAND VLYS...MTNS... AND DESERTS SHOULD BE NEARLY AS WARM AS MON. THE COOLING THAT BEGAN AT THE CST MON...WL EXTEND INTO THE LWR COASTAL VLYS TODAY. AS THE UPR TROUGH ARRIVES WED...MOST AREAS EXCEPT THE CST WL COOL SIGNIFICANTLY WITH GREATEST COOLING IN THE MTNS AND NRN DESERTS. A LTL ADDITIONAL COOLING IS POSSIBLE THU...THEN A LTL WARMER FOR FRI THRU THE WEEKEND BUT WITH INLAND TEMPERATURES REMAINING WELL BLO THOSE OF THIS PAST WEEKEND.

.SAN...NONE.

MARTIN