EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
AFDSAN 330 AM PST THU MAR 2 2000
...SYNOPSIS...
A PACIFIC STORM WILL MOVE TO NEAR THE CENTRAL CALIFORNIA COAST
TODAY...MOVE SOUTHEAST ALONG THE COAST TONIGHT...THEN STALL NEAR OR
OVER SOUTHERN CALIFORNIA FRIDAY AND SATURDAY...MOVING EAST SATURDAY
NIGHT AS ANOTHER PACIFIC STORM APPROACHES SOUTHERN CALIFORNIA FOR
SUNDAY. SCATTERED SHOWERS AND THUNDERSTORMS ARE EXPECTED FOR
SOUTHWEST CALIFORNIA TONIGHT THROUGH SATURDAY MORNING...WITH ANOTHER
CHANCE FOR SHOWERS SUNDAY AND MONDAY. SURF WILL BUILD OVER THE
COASTAL WATERS LATE TONIGHT AND FRIDAY.
...DISCUSSION...
00Z AVN TRENDING STRONGLY TOWARD STRONGER/SLOWER SOLUTION OF THE
ECMWF WITH THE PACIFIC STORM ALG 130W APPROACHING THE CNTRL CA CST.
THIS IS CONSISTENT WITH TRENDS THE PAST FEW WEEKS OF PAC STORMS
BEING STRONGER AND SLOWER THAN INITIALLY FORECAST BY THE MDLS (XCP
THE ECMWF) AS THE STORMS APPROACH THE CA CST. FOLLOWING THE AVN...
SFC CDFNT WL MOVE TO NEAR POINT CONCEPTION LATE THIS MORNING AND NR
CSTL LOS ANGELES COUNTY LATE THIS AFTERNOON. HOWEVER...WITH THE UPR
TROUGH CLOSING OFF JUST OFF THE CNTRL CA CST LATE THIS AFTERNOON
WITH THE CLOSED UPR CENTER MOVG SLOWLY SE JUST OFF THE CST TONIGHT
AND FRIDAY TO A POSITION OVR THE SRN CA CSTL WTRS EARLY FRI
MORNING... THE SFC CDFNT MAY NOT REACH SW CA AND LWR AND MID LVL
MSTR MAY BE SLOW TO MOVE ONSHR INTO THE FORECAST AREA THIS EVENING.
IF SYS IS A LTL SLOWER TO CLOSE OFF...THEN THE FRONT WOULD BRING A
PD OF RAIN THIS EVENING TO MUCH OF THE FORECAST AREA ALG AND W OF
THE MTNS. DUE TO TRACK AND INTENSITY UNCERTAINTIES AND THE IMPACTS
OF SUCH DIFFERENCES ON THE FORECAST...HAVE INCLUDED 50 PERCENT POPS
FOR MOST AREAS ALG AND W OF MTNS FOR TONIGHT. AS THE UPR CNTR...
ASSOCD MID LVL COLD POOL...AND ABUNDANT LOW AND MID LVL MSTR ARE
OVER THE FORECAST AREA...SHOWERS ARE A GOOD BET FOR MOST OF THE
FORECAST AREA FRI WITH A CHANCE FOR THUNDERSTORMS...ESPECIALLY IN
THE AFTERNOON. WITH THE POSSIBILITY THAT THE UPR CNTR COULD BE A LTL
FARTHER W... HAVE AGAIN OPTED ONLY FOR 50/60 PERCENT POPS FOR FRI.
HOWEVER...IF THE AVN IS A PERFECT PROG...HIGHER POPS WL BE IN ORDER
FOR FRI. HAVE INCREASED HIGH TEMPERATURES FOR CST/VLYS TODAY AS
RECENT ACARS SOUNDINGS SHOW POTENTIAL FOR VLY TEMPERATURES TO REACH
THE LOWER 70S THIS AFTERNOON. WITH TENDENCY FOR ELY LVL LOW FLOW TO
DEVELOP ACROSS SRN CA TODAY IN RESPONSE TO THE STRONG HEIGHT FALLS
OFF THE CST...WARM VLY TEMPERATURES COULD EXTEND TOWARD THE CST.
CSTL WTRS...SWAPS AND NOAA WAVE MDL A LTL SLOWER WITH INCR IN SURF
FOR SRN CA CST WITH SURF EXPECTED TO BUILD LATE TONIGHT AND FRI...TO
NR THE LOW END OF HVY SURF CRITERIA FOR FRIDAY AFTERNOON AND NIGHT.
EXTENDED...MRF/ECMWF CONSISTENT IN EJECTING SRN CA/NRN BAJA CLOSED
LOW E LATE SAT AND SAT NIGHT AS NEXT PACIFIC STORM DIGS TOWARD SRN
CA. ECMWF/MRF THEN DIVERGE WITH MRF BRINGING CLOSED UPR CNTR TO
CNTRL CA SUN AND SRN CA MON. ECWMF KEEPS THE CLOSED UPR CNTR OFF THE
SRN CA CST FOR SUN AND MON...THEN MOVES IT EAST INTO SRN CA TUE. DUE
TO THE BIG DIFFERENCES SUCH SOLNS WOULD HAVE ON WEATHER IN SW
CA...HAVE GROUPED SUN/MON TOGETHER USING MOSTLY CLOUDY/CHANCE OF
SHOWERS WORDING FOR MOST ZONES.
SAN 055
.SAN...NONE.
MARTIN