AREA FORECAST DISCUSSION

 
 FXUS66 KSGX 241117
 AFDSGX
 
 AREA FORECAST DISCUSSION...UPDATED
 NATIONAL WEATHER SERVICE SAN DIEGO CA
 330 AM PST TUE NOV 24 2009
 
 .SYNOPSIS...HIGH PRESSURE ALOFT AND WEAK OFFSHORE FLOW WILL BRING 
 CLEAR SKIES WITH WARMER DAYS THROUGH THURSDAY. LOCAL GUSTY WINDS 
 THROUGH AND BELOW MOUNTAIN CANYONS AND PASSES. COOLER FRIDAY THROUGH 
 THE WEEKEND AS LOW PRESSURE MOVES PAST TO THE NORTH. LOCAL GUSTY 
 OFFSHORE WINDS AGAIN SUNDAY AND MONDAY. 
 
 &&
 
 .DISCUSSION...FOR SOUTHWEST CALIFORNIA INCLUDING SAN DIEGO... 
 ORANGE...SOUTHWEST SAN BERNARDINO AND WEST RIVERSIDE COUNTIES.
 
 .SHORT TERM (TODAY-THURSDAY)...SKIES WERE CLEAR EARLY THIS MORNING. 
 LOCALLY GUSTY WINDS WERE OCCURRING BELOW THE PASSES AND CANYONS. MOST 
 GUSTS HAVE BEEN BELOW 35 MPH...HOWEVER ISOLATED STRONGER GUSTS HAVE 
 BEEN OBSERVED INCLUDING 74 MPH AT FREMONT CANYON AND 66 MPH AT SAN 
 BERNARDINO. OFFSHORE PRESSURE GRADIENTS WITH ABOUT -11 MB SAN-TPH 
 AND -1 MB SAN-IPL. 
 
 RIDGING ALOFT AND OFFSHORE FLOW WILL CONTINUE CLEAR SKIES WITH 
 WARMER DAYS. TEMPERATURES WILL INCREASE A LITTLE EACH DAY...WITH THE 
 WARMEST DAY OCCURRING ON THANKSGIVING. MAX TEMPS ON THANKSGIVING WILL 
 BE ABOUT 5 TO 10 DEGREES ABOVE SEASONAL AVERAGES EXCEPT ALONG THE 
 IMMEDIATE COAST WHERE TEMPS WILL BE CLOSER TO AVERAGE. THE OFFSHORE 
 FLOW WILL MAINLY BE GRADIENT DRIVEN WITH WEAK UPPER AND THERMAL 
 SUPPORT. ADVISORY STRENGTH WINDS WILL OCCUR IN THE INLAND EMPIRE AND 
 SANTA ANA MOUNTAINS AND FOOTHILLS THIS MORNING...OTHERWISE WINDS ARE 
 EXPECTED TO REMAIN BELOW 35 MPH THROUGH THURSDAY WITH ONLY ISOLATED 
 STRONGER GUSTS AT TIMES IN THE MOST WIND PRONE AREAS. THE WARM AND 
 DRY OFFSHORE FLOW WILL MAINTAIN AN ELEVATED FIRE WEATHER HAZARD. 
 
 &&
 
 .LONG TERM (FRIDAY-MONDAY)...AN UPPER TROUGH WILL MOVE PAST TO THE N 
 FRIDAY BRINGING COOLING AND HIGHER HUMIDITIES WITH A RETURN OF 
 ONSHORE FLOW. THERE WILL BE A BRIEF RETURN OF MARINE LAYER CLOUDS 
 AND VARIABLE HIGH CLOUDINESS FRIDAY AND SATURDAY. ANOTHER STRONGER 
 TROUGH SHOULD MOVE PAST TO THE N AND E SUNDAY BRINGING POTENTIALLY 
 STRONG AND COOL N TO NE WINDS. THE OFFSHORE WINDS WILL WEAKEN 
 MONDAY. 
 
 &&
 
 .AVIATION...
 241000Z...MAIN AVIATION WEATHER CONCERN IS TURBULENCE FROM STRONG NE 
 TO E WINDS POURING THROUGH MOUNTAIN PASSES. REMOTE SURFACE STATIONS 
 NEAR THESE GAPS ARE SHOWING SUSTAINED 25KT WITH GUSTS 35-55KT. TREND 
 SINCE 24/0600 UTC HAS BEEN DOWNWARD AND ALL MODELS CONCUR WITH 
 THIS...WITH SUSTAINED NE TO E WINDS DIMINISHING TO 10-15KT BELOW 
 FL100 BY 1800 UTC. CEILING AND VISIBILITY WILL CONTINUE UNLIMITED 
 FOR ANOTHER 48-60 HOURS UNDER HIGH PRESSURE WITH THE LIGHTER NE TO E 
 WINDS CONTINUING FLOW. 
 
 &&
 
 .SGX WATCHES/WARNINGS/ADVISORIES...
 CA...WIND ADVISORY UNTIL NOON PST TODAY FOR SAN BERNARDINO AND 
      RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-SANTA ANA 
      MOUNTAINS AND FOOTHILLS.
 
 PZ...NONE.
 
 &&
 
 

 
 PUBLIC/FIRE WEATHER...SCV 
 AVIATION/MARINE...BALFOUR
 
 
 
 
 

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