EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
AFDSAN 300 AM PST TUE MAR 20 2001
...SYNOPSIS...
HIGH PRESSURE OVER SOUTHERN CALIFORNIA WILL SLOWLY WEAKEN TODAY
THROUGH THURSDAY. THIS WILL BRING A GRADUAL COOLING TREND BEGINNING
TODAY AT THE COAST...SPREADING INLAND WEDNESDAY AND THURSDAY.
HIGH PRESSURE WILL REBUILD FRIDAY THROUGH THE WEEKEND WITH A WARMING
TREND. SPRING BEGINS THIS MORNING AT 531 AM.
...DISCUSSION...
ETA/AVN PREFERRED IN THE NR TERM...MRF/ECMWF IN THE EXTENDED. WK
CSTL EDDY EVIDENT THIS MORNING AS FORECAST BY THE HIGHER RESOLUTION
MDLS. MON EVENING ACARS SOUNDINGS SHOWED THE BASE OF A SHALLOW
MARINE INVERSION NR 500 WITH THE TOP OF THE INVERSION BLO 1000 FT.
COAMPS CROSS SECTIONS SHOW SOME MINOR ADDITIONAL DEEPENING TONIGHT
INTO WED MORNING CONSISTENT WITH MINOR WKNG OF THE UPR RDG OVR SRN
CA. PATCHY DENSE FOG IS POSSIBLE NR THE CST THIS MORNING...THEN
GREATER STRATUS COVERAGE LATE TONIGHT INTO WED MORNING WITH SOMEWHAT
GREATER INLAND PENETRATION...INTO THE MESAS OR LWR CSTL VLYS WITH
DEPTH OF MARINE LYR INCRG TO 1200 TO 1500 FT. SOME MINOR COOLING
INLAND TODAY XCP THE DESERTS...THEN GREATER COOLING INLAND
WED...ESPECIALLY W OF THE MTNS...DUE TO MARINE LYR DEEPENING AND
SOME INCR IN THE STRENGTH OF THE AFTERNOON ONSHORE FLOW. THU APPEARS
TO BE THE "COOLEST" DAY...THEN A SLOW WARMING TREND INTO THE WEEKEND
AS WK HIGH PRESSURE BUILDS OVR SRN CA AND LOW LVL ONSHR FLOW WKNS.
PATCHY NIGHT AND MORNING LOW CLOUDS AND FOG WL CONTINUE NR THE CST
WITH A FEW HIGH CLOUDS AT TIMES...MOSTLY CLR OTHERWISE.
SAN 000
.SAN...NONE.
MARTIN