EXTREME SOUTHWESTERN CALIFORNIA AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
AFDSAN 745 PM PST TUE FEB 1 2000
...SYNOPSIS...
HIGH PRESSURE BUILDING OVER THE SOUTHWEST WILL BRING WARM DAYS AND
CLEAR COOL NIGHTS THROUGH THURSDAY. OFFSHORE FLOW WILL BRING 15 TO
30 MPH WINDS IN SOME PASSES AND CANYONS THROUGH WEDNESDAY MORNING.
THE NEXT CHANCE FOR RAIN WILL BE FRIDAY WHEN A PACIFIC STORM IS
FORECAST TO REACH SOUTHERN CALIFORNIA.
...DISCUSSION...
A RIDGE OF HIGH PRESSURE OVER THE WEST COAST ALONG WITH OFFSHORE
PRESSURE GRADIENTS OF NEARLY 7 MBS BETWEEN KSAN AND KTPH AND 2 MBS
BETWEEN KSAN AND KIPL HAS RESULTED IN A MOSTLY CLEAR SKY ACROSS THE
CWFA THIS EVENING WITH THE CLEAR SKY EXTENDING WELL OFFSHORE OVER
THE COASTAL WATERS. 00Z NKX SOUNDING SHOWED A NORTHEAST TO EASTERLY
WIND 15 TO 20 KTS AT LOW LEVELS AND THIS IS SUPPORTED BY KNKX 88D
VWP AND RECENT ACARS SOUNDING INTO KSAN. THE WIND IS HELPING TO KEEP
TEMPS UP ABOUT 8 TO 12 DEGREES OVER 24 HOURS AGO IN MOST PLACES
AROUND THE CWFA AFTER AN UNSEASONABLY WARM DAY. NO RECORDS WERE SET
HOWEVER.
APPEARS WEDNESDAY WILL BE ANOTHER CLEAR VERY WARM DAY ACROSS THE
CWFA BUT A QUICK LOOK AT THE RECORD MAXIMUM TEMPERATURES FOR FEB 2
IT DOES NOT APPEARS MANY RECORDS WILL BE SET. RECORDS FOR FEB 2 ARE
HIGHER THAN THE RECORDS FOR TODAY WHICH SHOULD JUST ABOUT COINCIDE
WITH THE TEMPERATURE INCREASE EXPECTED ON WEDNESDAY.
00Z ETA MODEL KEEPS THE OFFSHORE FLOW IN PLACE THROUGH WEDNESDAY
THEN TURNING MORE SOUTHEASTERLY ON THURSDAY IN RESPONSE TO THE S/WV
TROUGH/LOW AND ASSOCIATED SURFACE LOW APPROACHING FROM THE WEST ON
THURSDAY. THE ETA INDICATES VERY LITTLE MOISTURE REACHING THE CWFA
THROUGH THURSDAY AFTERNOON. TIMEHEIGHT CROSS SECTION FROM THE ETA
MODEL FOR KSAN DOES SHOW AN AREA OF 50 PERCENT OR GREATER JUST
SHOWING UP BETWEEN 700 AND 600 MBS AT 48 HOURS...THURSDAY AFTERNOON.
THE ETA MODEL IS IN FAIRLY GOOD AGREEMENT WITH THE EARLIER AVN MODEL
SUGGESTING THE S/WV WILL SWING INLAND THURSDAY NIGHT OR FRIDAY.
TIMING ON THE CURRENT FORECAST PACKAGE BRINGING PCPN INTO THE AREA
ON FRIDAY LOOKS GOOD.
NO UPDATES ARE PLANNED BUT THE MID SHIFT SHOULD CONSIDER TWEAKING UP
TEMPS A COUPLE DEGREES AT A NUMBER OF LOCATIONS OVER THE HIGH
TEMPERATURES TODAY...ESPECIALLY THE INLAND EMPIRE AREA COULD GET
INTO THE LOW 80S.
SAN 0000
.SAN...NONE
HORTON