AREA FORECAST DISCUSSION

 
 FXUS66 KSGX 220538
 AFDSGX
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE SAN DIEGO CA
 935 PM PST SAT NOV 21 2009
 
 .SYNOPSIS...MOSTLY CLEAR WITH A WARMING TREND THROUGH THE MIDDLE OF 
 NEXT WEEK UNDER BUILDING HIGH PRESSURE AND WEAK OFFSHORE FLOW.
 
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 .DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO... 
 ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.
 
 TEMPERATURES TODAY WERE SEVERAL DEGREES LOWER THAN YESTERDAY...AND 
 IN SOME PLACES (BEAUMONT) IT WAS A FULL 10 DEGREES LOWER. THE 
 DOWNWARD SLIDE CONTINUES TONIGHT WHERE IT WILL BE QUITE COOL WITH 
 TEMPS BOTTOMING OUT IN THE UPPER 30S AND LOW 40S IN THE INLAND 
 VALLEYS. LOWS WILL FALL INTO THE TEENS IN THE SOME OF THE COLD AIR 
 DRAINAGE AREAS OF THE SAN BERNARDINO MOUNTAINS (BALDWIN LAKE).
 
 CLOUD COVER FROM THE MARINE LAYER THIS EVENING IS SPOTTY. MOST OF 
 THE REGION WAS CLEAR AT 9 PM. WEAK RIDGING ALOFT AND LIGHT OFFSHORE 
 FLOW WILL KEEP SKIES MOSTLY CLEAR THROUGH SUNDAY MORNING. 
 TEMPERATURES WILL REBOUND QUICKLY TOMORROW AFTER SUNRISE. 
 
 ON SUNDAY NIGHT AND MONDAY WEAK UPPER LEVEL TROUGHING WILL BRIEFLY 
 NEUTRALIZE THE OFFSHORE PRESSURE PATTERN. BUT IT TURNS AROUND 
 QUICKLY ON MONDAY NIGHT AND TUESDAY WHEN A SLIGHTLY STRONGER 
 OFFSHORE FLOW ARRIVES. EXPECT CLEAR SKIES AND WARMER WEATHER EACH 
 DAY THROUGH THURSDAY UNDER THIS WEATHER PATTERN. WEAK TO MODERATE 
 SANTA ANA WINDS ARE FORECAST TUESDAY THROUGH THURSDAY...BUT WILL 
 REMAIN BELOW ADVISORY LEVELS.
 
 COOLING NEXT WEEKEND WHEN THE HIGH OVER THE GREAT BASIN IS REPLACED 
 BY A PACIFIC TROUGH BRINGING COOLER WEATHER AND THE RETURN OF 
 ONSHORE FLOW. 
 
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 .AVIATION...
 230530Z...THE MARINE LAYER LOW CLOUDS ARE EXPECTED TO DISSIPATE BY 
 EARLY SUNDAY MORNING AS WEAK OFFSHORE FLOW CONTINUES TO DEVELOP OVER 
 THE REGION. MOSTLY VFR CONDITIONS THROUGH MONDAY. LIGHT OFFSHORE 
 FLOW NIGHTS AND MORNINGS...WITH SOUTHWEST TO WEST SEA BREEZE WINDS 
 IN THE AFTERNOONS.
 
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 .FIRE WEATHER...
 NO SHORT TERM FIRE WEATHER CONCERNS. NEXT CONCERN IS THE PROLONGED 
 OFFSHORE WIND PATTERN FOR NEXT WEEK. THIS STILL LOOKS LIKE A WEAK TO 
 BRIEFLY MODERATE EVENT...PEAKING ON TUESDAY. ADDED FORECAST WIND 
 GUSTS AND RH VALUES TO THE EXTENDED PORTION OF EACH FIRE WEATHER 
 ZONE FORECAST IN THIS AFTERNOONS. LOOKING FURTHER OUT...ASSUMING THE 
 MODELS ARE DEAD ON ACCURATE WITH THE STRENGTH AND POSITION OF THE 
 RIDGE...A MUCH STRONGER OFFSHORE WIND EVENT IS ADVERTISED TO FINISH 
 OUT THE MONTH OF NOVEMBER.
 
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 .SGX WATCHES/WARNINGS/ADVISORIES...NONE.
 
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 $$
 
 PUBLIC...MOEDE
 AVIATION...SMALL
 FIRE WEATHER...BALFOUR