AREA FORECAST DISCUSSION

 
 FXUS66 KLOX 241719
 AFDLOX
 
 SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
 900 AM PST TUE NOV 24 2009
 
 .SYNOPSIS...
 
 IT WILL BE CLEAR AND WINDY THROUGH THANKSGIVING DAY WITH DAY TIME 
 TEMPERATURES ABOVE NORMAL ACROSS THE COASTS AND VALLEYS. THE WEATHER 
 WILL ABRUPTLY CHANGE FRIDAY AS THE MARINE LAYER WILL REFORM AND  
 TEMPERATURES WILL FALL 10 TO 15 DEGREES OVER MOST AREAS. IT WILL 
 REMAIN COOL SATURDAY BEFORE ANOTHER WARMING TREND STARTS SUNDAY.
 
 &&
 
 .SHORT TERM (TODAY-THU)...AN UPDATE IS NOT ANTICIPATED AT THIS TIME. 
 GUIDANCE INITIALIZED WELL WITH A LOW AMPLITUDE RIDGE OF HIGH 
 PRESSURE CENTERED OVER THE AREA AND CONSISTENT WITH PREVIOUS RUNS.
 WILL ISSUE AN UPDATE AROUND NOON TO REMOVE THE HEADLINES AS THE 
 NORTHEAST WINDS SUBSIDE.
 
 THE FOLLOWING FROM THE PREVIOUS SHIFT 
 
 KDAG GRAD IS NR -6 AND KBFL GRAD IS NEAR -5. A LITTLE COLD AIR 
 ADVECTION IS ALSO COMING IN FROM THE NE AND THIS HAS SET UP A GOOD 
 OFFSHORE EVENT WITH MANY GUSTS BETWEEN 45 AND 55 MPH REPORTED IN THE 
 AREAS SUSCEPTIBLE TO NE WINDS. MAX TEMPS WILL BE MANY DEGREES ABOVE 
 NORMAL TODAY FOR THE COASTS AND VALLEYS BUT NOT NEAR RECORD LEVELS 
 AS THE THKNS IS ONLY 563 DM. STILL LOOK FOR MANY READING NEAR 80 
 DEGREES TODAY WITH THE WARMEST READINGS ON THE COAST WHERE 
 DOWNSLOPING COMPRESSIONAL HEATING WILL HAVE THE GREATEST EFFECT. MAX 
 TEMPS OVER THE MTNS AND INLAND AREAS WILL BE MUCH COOLER. THE WINDS 
 WILL SUBSIDE TO BELOW ADVISORY LEVELS LATER THIS MORNING.
 
 THE WINDS WILL AGAIN PICK UP TONIGHT. THEY WILL BE WEAKER THAN 
 TONIGHT AS THE GRADS WILL BE A LITTLE WEAK AND THERE NO LONGER BE 
 ANY COLD AIR ADVECTION. THE WINDS WILL BE VERY CLOSE TO ADVISORY 
 CRITERIA. LOWS TEMPS TONIGHT WILL BE VERY TRICKY WITH THE CLEAR 
 SKIES AND DRY AIR ANY WIND SHELTERED AREAS WILL SEE VERY COLD 
 READINGS WHILE WINDY AREAS WILL SEE READINGS 20 TO 25 DEGREES WARMER.
 
 WEDNESDAY WILL BE MUCH LIKE TODAY JUST A LITTLE LESS WINDY WITH MAX 
 TEMPS WITHIN A DEGREE OF TODAYS ACROSS THE COASTS AND VALLEY. THE 
 INLAND AREAS WILL WARM A FEW DEGREES SINCE THERE WILL BE NO MORE 
 COLD AIR ADVECTION.
 
 CHAMBER OF COMMERCE THANKSGIVING DAY. SOME MILD NON ADVISORY 
 OFFSHORE WINDS IN THE MORNING ACROSS THE FAVORED LOCATIONS. SUNNY 
 SKIES AND MAX TEMPS IN THE 70S FOR MOST OF THE COASTAL AND VALLEY 
 LOCATIONS.
 
 .LONG TERM (FRI-MON)...
 THE EC AND THE GFS ARE IN PRETTY GOOD AGREEMENT FOR THE EXTENDED 
 PERIOD (AT LEAST ACROSS THE WEST COAST - THE EAST COAST NOT SO MUCH) 
 AND DO NOT DEVIATE FROM THE PREVIOUS THINKING. A DRY FRONT WILL MOVE 
 ACROSS THE AREA FRIDAY SWITCHING THE OFFSHORE FLOW TO ONSHORE FLOW 
 AND DROPPING HGTS BY MANY DM. THE NAM DOES NOT SUPPORT AS MUCH OF A 
 MARINE LAYER AS THE CURRENT FORECAST HAS IN IT BUT WILL HOLD THE 
 LINE FOR NOW. BIG THING IS THE DROP IN TEMPS WHICH WILL BE ANYWHERE 
 FROM 10 TO 20 DEGREES COOLER THAN THURSDAYS VALUES.
 
 SATURDAY WILL BE ANOTHER COOL DAY AS HGTS LOWER EVEN MORE.
 
 RIDGING...OFFSHORE FLOW AND WARMING ARE STILL FORECAST FOR NEXT 
 SUNDAY AND MONDAY. 
 
 &&
 
 .AVIATION...
 
 24/1130Z.
 
 VFR CONDS THROUGH TONIGHT. MODERATE WINDS THROUGH THE PASSES AND 
 CANYONS WILL CAUSE MDT ISOLD SVR TURBC IN AND AROUND HIER TRRN.
 
 KLAX...VERY GOOD CONFIDENCE IN CAVU TAF.
 
 KBUR...VERY GOOD CONFIDENCE IN CAVU CIG/VIS FCST. WINDS WILL BE 
 ERRATIC THROUGH THE PERIOD. PERIODS OF MDT-ISOLD SVR TURBC SFC-070 
 AND LOW LEVEL WIND SHEAR THROUGH WED MORNING.
 
 &&
 
 .LOX WATCHES/WARNINGS/ADVISORIES...
 WIND ADVISORY (SEE LAXNPWLOX).
 SMALL CRAFT ADVISORY (SEE LAXMWWLOX).
 
 &&
 
 

 
 PUBLIC...RORKE/30
 AVIATION...KAPLAN
 SYNOPSIS...ASR
 
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