Forecast Discussions mentioning ACARS, received at FSL on 03/13/00

...SYNOPSIS... VERY WEAK LOW PRESSURE TROUGH TONIGHT AND MONDAY WILL GRADUALLY BE REPLACED BY HIGH PRESSURE ALOFT MONDAY NIGHT AND TUESDAY. THE LOW CLOUDS AND FOG OF TONIGHT WILL DECREASE IN THE COMING NIGHTS AS THE SURFACE FLOW TRENDS OFFSHORE. TEMPERATURES WILL INCREASE ON TUESDAY. ABOVE-NORMAL TEMPERATURES ARE EXPECTED WEDNESDAY THROUGH THE END OF THE WEEK.

...DISCUSSION... WE CURRENTLY HAVE AN EDDY...AND IT IS FAIRLY CLOSE TO THE COAST AS WINDS ARE SE AT LINDBERGH...BUT AT MOST OF THE BUOYS...WINDS ARE W-NW. EXPECT THIS EDDY TO CONTINUE UNTIL THE WEAK TROUGH GOES THROUGH MONDAY...SO THIS WILL BRING QUITE A LOT OF LOW CLOUDS TONIGHT WITH SOME DENSE FOG IN THE INLAND VALLEYS...AT LEAST THE WEST PARTS. ACARS AND SURFACE OBS SHOW THE INVERSION SOMEWHERE BETWEEN 1000 AND 1500 FEET...SO THAT WOULD MAKE THE WESTERN VALLEYS FOGGY LATE TONIGHT. AFTER THE TROUGH GOES BY...THE FLOW WILL BECOME MORE NORTHERLY ALOFT...BUT THE HIGH PRESSURE AT THE SURFACE OVER NEVADA/UTAH MONDAY NIGHT AND TUESDAY WILL BE LIMITED BY STRONG LOW PRESSURE MOVING INTO SW CANADA/FAR NW US. ALSO...TEMPERATURE GRADIENTS ALOFT WILL BE WEAK...SO I DO NOT EXPECT TOO STRONG OF OFFSHORE FLOW TUESDAY...AND THE COAST WILL STILL HAVE THE SEA BREEZE. FOG MAY BECOME DENSE MONDAY NIGHT IN MORE AREAS...ESPECIALLY ALONG THE SAN DIEGO COUNTY MESAS...BUT INLAND AREAS WILL BE MORE CLEAR. EVEN THOUGH THE COAST WILL BE SLOWER TO WARM...INLAND AREAS SHOULD BE QUITE WARM TUESDAY...LIKELY ABOVE THE CURRENT FORECAST NUMBERS.

ALL AREAS SHOULD BE WARMER WEDNESDAY DUE TO STRENGTHENING OF SURFACE HIGH PRESSURE OVER NV/UT AS THE LOW MOVES EAST INTO THE PLAINS OF CANADA/NORTHERN US.

THE CURRENT FORECAST LOOKS FINE FOR NOW...SO NO UPDATE WILL BE ISSUED.

SAN 0000

.SAN...NONE.

MAXWELL



CORRECTION TO SYNOPSIS

...SYNOPSIS... A COASTAL EDDY AND A DEEP MARINE LAYER WILL KEEP LOW CLOUDS AND FOG NEAR THE COAST TODAY. THE INLAND VALLEYS SHOULD BE MOSTLY SUNNY BY MID MORNING. THE MOUNTAINS AND DESERTS WILL ENJOY BEAUTIFUL SPRINGLIKE WEATHER TODAY. A TREND TOWARDS OFFSHORE FLOW TONIGHT WILL LOWER THE MARINE LAYER...BUT RESULT IN MORE WIDESPREAD DENSE FOG WEST OF THE MOUNTAINS. THE TREND TOWARDS OFFSHORE FLOW WILL CONTINUE TUESDAY AS HIGH PRESSURE BUILDS ALOFT. TEMPERATURES WILL INCREASE MOST AREAS TUESDAY AND WARM ALONG THE COASTS WEDNESDAY. ABOVE NORMAL TEMPERATURES SHOULD CONTINUE ON THURSDAY.

...DISCUSSION... RECENT ACARS AND VAD WINDS INDICATE THE BASE OF THE INVERSION/MARINE LAYER HAS DEEPENED TO AROUND 4000 FEET DUE TO UPWARD VERTICAL MOTION CAUSED BY THE SHORT WAVE PASSING OVERHEAD. THE MESOETA TAKES THE CENTER OF THE EDDY CIRCULATION SOUTH TO VICINITY MTTJ BY 18Z THEN MOVES IT ONSHORE AND BECOMES ABSORBED BY THERMAL TROUGH. EXITING S/WV TURNS FLOW UPPER LEVEL FLOW TO NW AND MID LEVEL FLOW TO N-NE BY THIS EVENING. THE SURFACE PRESSURE GRADIENTS KSAN-KIPL INCREASE TO +5 MB THIS AFTERNOON THROUGH TONIGHT. WITH STRONGER ONSHORE FLOW AND PROLONGED CLOUD COVER ACROSS SAN DIEGO COASTS/VALLEYS TODAY WILL ADJUST TEMPS DOWNWARD AND MENTION BREEZY ACROSS ALL SAN DIEGO COUNTY ZONES AND COACHELLA VALLEYS TODAY...CONTINUING OVER DESERTS TONIGHT. FOR THE OTHER MOUNTAINS AND HIGH DESERTS/VALLEYS...BREEZY IS SOMEWHAT IN QUESTION. MODEL 700/850 MB WINDS BARELY ABOVE 10 KTS THROUGH NEXT 2 DAYS AND OFFSHORE PRESSURE GRADIENTS NOT THAT IMPRESSIVE. HOWEVER WILL ASSUME EDDY WILL NOT REGENERATE TONIGHT AND INLAND VALLEYS WILL START OFF WITH LESS CLOUD COVER TUESDAY MORNING AND BE UNDER THE INFLUENCE OF WEAK SUBSIDENCE FOR A GENERAL WARMING TREND. ORANGE COUNTY COAST MAY GET THE OFFSHORE FLOW/WARMING TUESDAY BUT EXPECT SAN DIEGO COASTS WILL NOT...HENCE WARMING THERE WILL DELAYED UNTIL WEDNESDAY.

IN THE MEDIUM RANGE...BELIEVE THE AVN/MRF SOLUTION MAY BE A LITTLE TOO FAST ON SPINNING UP A CLOSED LOW OFF THE CENTRAL/SW CA COAST ON WED/THU BUT THE IDEA HAS MERIT. THE ECMWF AND THE LATEST AVAILABLE UKMET AND NOGAPS HAVE SAME SOLUTION BUT SLOWER. SUPPORT SEEN WITH TROPICAL UPPER TROPOSPHERIC LOW CURRENTLY VICINITY 15N/140W MOVING ENE AND/OR OPENING UP INTO A TROUGH EXTENDING ACROSS 25N/130W BY THURSDAY...IF NOT SOONER. IN THE DAY 3 THROUGH 5 FORECAST PERIOD THE MAIN EFFECTS ON SW CALIFORNIA ARE TO BUILD THE RIDGE AND INCREASE THICKNESSES RESULTING IN WARMING TREND. MAY SPLIT OUT DAY 5 AND INTRODUCE INCREASING HIGH CLOUDS IF TIME PERMITS... OTHERWISE HIGH AND DRY THROUGH THURSDAY...BU DO NOT EXPECT THIS WILL CONTINUE INTO NEXT WEEKEND.

SAN 000

.SAN...NONE.

BALFOUR

...SYNOPSIS... A COASTAL EDDY AND A DEEP MARINE LAYER WILL KEEP LOW CLOUDS AND FOG NEAR THE COAST TODAY. THE INLAND VALLEYS SHOULD BE MOSTLY SUNNY BY MID MORNING. THE MOUNTAINS AND DESERTS SHOULD ENJOY BEAUTIFUL SPRINGLIKE WEATHER TODAY. A TREND TOWARDS OFFSHORE TONIGHT WILL LOWER THE MARINE LAYER...BUT MAY RESULT IN MORE WIDESPREAD DENSE FOG WEST OF THE MOUNTAINS. THE TREND TOWARDS OFFSHORE FLOW WILL CONTINUE TUESDAY AS HIGH PRESSURE BUILDS ALOFT. TEMPERATURES WILL INCREASE MOST AREAS TUESDAY AND WARM ALONG THE COASTS WEDNESDAY. ABOVE NORMAL TEMPERATURES SHOULD CONTINUE ON THURSDAY.

...DISCUSSION... RECENT ACARS AND VAD WINDS INDICATE THE BASE OF THE INVERSION/MARINE LAYER HAS DEEPENED TO AROUND 4000 FEET DUE TO UPWARD VERTICAL MOTION CAUSED BY THE SHORT WAVE PASSING OVERHEAD. THE MESOETA TAKES THE CENTER OF THE EDDY CIRCULATION SOUTH TO VICINITY MTTJ BY 18Z THEN MOVES IT ONSHORE AND BECOMES ABSORBED BY THERMAL TROUGH. EXITING S/WV TURNS FLOW UPPER LEVEL FLOW TO NW AND MID LEVEL FLOW TO N-NE BY THIS EVENING. THE SURFACE PRESSURE GRADIENTS KSAN-KIPL INCREASE TO +5 MB THIS AFTERNOON THROUGH TONIGHT. WITH STRONGER ONSHORE FLOW AND PROLONGED CLOUD COVER ACROSS SAN DIEGO COASTS/VALLEYS TODAY WILL ADJUST TEMPS DOWNWARD AND MENTION BREEZY ACROSS ALL SAN DIEGO COUNTY ZONES AND COACHELLA VALLEYS TODAY...CONTINUING OVER DESERTS TONIGHT. FOR THE OTHER MOUNTAINS AND HIGH DESERTS/VALLEYS...BREEZY IS SOMEWHAT IN QUESTION. MODEL 700/850 MB WINDS BARELY ABOVE 10 KTS THROUGH NEXT 2 DAYS AND OFFSHORE PRESSURE GRADIENTS NOT THAT IMPRESSIVE. HOWEVER WILL ASSUME EDDY WILL NOT REGENERATE TONIGHT AND INLAND VALLEYS WILL START OFF WITH LESS CLOUD COVER TUESDAY MORNING AND BE UNDER THE INFLUENCE OF WEAK SUBSIDENCE FOR A GENERAL WARMING TREND. ORANGE COUNTY COAST MAY GET THE OFFSHORE FLOW/WARMING TUESDAY BUT EXPECT SAN DIEGO COASTS WILL NOT...HENCE WARMING THERE WILL DELAYED UNTIL WEDNESDAY.

IN THE MEDIUM RANGE...BELIEVE THE AVN/MRF SOLUTION MAY BE A LITTLE TOO FAST ON SPINNING UP A CLOSED LOW OFF THE CENTRAL/SW CA COAST ON WED/THU BUT THE IDEA HAS MERIT. THE ECMWF AND THE LATEST AVAILABLE UKMET AND NOGAPS HAVE SAME SOLUTION BUT SLOWER. SUPPORT SEEN WITH TROPICAL UPPER TROPOSPHERIC LOW CURRENTLY VICINITY 15N/140W MOVING ENE AND/OR OPENING UP INTO A TROUGH EXTENDING ACROSS 25N/130W BY THURSDAY...IF NOT SOONER. IN THE DAY 3 THROUGH 5 FORECAST PERIOD THE MAIN EFFECTS ON SW CALIFORNIA ARE TO BUILD THE RIDGE AND INCREASE THICKNESSES RESULTING IN WARMING TREND. MAY SPLIT OUT DAY 5 AND INTRODUCE INCREASING HIGH CLOUDS IF TIME PERMITS... OTHERWISE HIGH AND DRY THROUGH THURSDAY...BU DO NOT EXPECT THIS WILL CONTINUE INTO NEXT WEEKEND.

SAN 000

.SAN...NONE.

BALFOUR