FXUS66 KSGX 201134
AFDSGX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
335 AM PST TUE JAN 20 2009
.SYNOPSIS...
WARM DRY WEATHER WILL CONTINUE INTO WEDNESDAY FOR INLAND AREAS UNDER 
WEAKENING HIGH PRESSURE WITH SLOW COOLING  SPREADING INLAND SLOWLY 
FROM THE COAST. FOR LATE WEDNESDAY NIGHT THROUGH THURSDAY...A TROUGH 
OF LOW PRESSURE WILL BRING PRECIPITATION TO MOST AREAS FROM THE 
COAST TO THE MOUNTAINS. DRY FOR FRIDAY AND EARLY SATURDAY UNDER WEAK 
HIGH PRESSURE...THEN ANOTHER CHANCE FOR SHOWERS FOR LATE SATURDAY 
INTO SUNDAY. 
&&
.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...
.SHORT TERM (TODAY THROUGH THURSDAY)...
HIGH PRESSURE WILL SLOWLY WEAKEN THROUGH WEDNESDAY WITH WEAK 
OFFSHORE SURFACE FLOW. SLOW COOLING WILL BEGIN TO SPREAD INLAND FROM 
THE COAST TODAY AND WEDNESDAY AND SOME PATCHY STRATUS MAY RETURN 
NEAR THE COAST TONIGHT INTO WEDNESDAY MORNING. THERE WILL CONTINUE 
TO BE A FLOW OF MOISTURE ALOFT FROM THE SOUTH BRINGING SOME HIGH 
CLOUDS. THE ECMWF IS GENERALLY FAVORED WITH THE SYSTEM FOR WEDNESDAY 
NIGHT AND THURSDAY...ESPECIALLY WITH THE INTENSITY. IT SHOULD BE 
NOTED THAT THE GFS AND NAM ARE NOW TRENDING CLOSER TO THE PREFERRED 
ECMWF (I.E. WEAKER AND SLOWER). THIS WOULD BRING PRECIPITATION TO 
MOST AREAS FROM THE COAST TO THE MOUNTAINS FOR LATE WEDNESDAY NIGHT 
THROUGH THURSDAY MORNING. POPS HAVE BEEN INCREASED CLOSER TO THE 
SREF. AMOUNTS ARE EXPECTED TO RANGE FROM AROUND ONE QUARTER INCH AT 
THE COAST TO ONE HALF INCH ON THE COASTAL MOUNTAIN SLOPES.
&&
.LONG TERM (FRIDAY THROUGH MONDAY)...
ECMWF PREFERRED THROUGH THE EXTENDED. WEAK SHORTWAVE RIDGING SHOULD 
BRING DRYING AND MINOR WARMING FOR FRIDAY AND EARLY SATURDAY THOUGH 
STILL WITH A DECENT AMOUNT OF CLOUDS. A TROUGH OF LOW PRESSURE IN 
NORTHWEST FLOW MAY BRING A CHANCE OF PRECIPITATION LATE IN THE 
WEEKEND WITH COOLER MOIST CYCLONIC FLOW CONTINUING INTO MONDAY.
&&
.AVIATION...
201000Z...EXPECT MID 15K TO HIGH 20K BROKEN TO OVERCAST CLOUDS TODAY 
THROUGH THIS EVENING...OTHERWISE VFR. LOCAL GUSTY NE WINDS TO 25 KT 
BELOW PASSES WILL CONTINUE THIS MORNING THEN DECREASE. MID CLOUDS 
WILL THICKEN AND LOWER TO 10K FEET LATE TONIGHT THROUGH WED MORNING 
AS AN UPPER LOW APPROACHES FROM THE WEST...WITH A CHANCE OF 
SCATTERED LIGHT SHOWERS DEVELOPING BY MID DAY WED.
&&
.SGX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.
&&
$$
PUBLIC...MARTIN
AVIATION/MARINE...MACKECHNIE
NWS ON THE WEB AT WEATHER.GOV/SANDIEGO