Area Forecast Discussion
Issued by NWS Los Angeles, CA

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000 FXUS66 KLOX 242337 AFDLOX SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA 340 PM PST SAT JAN 24 2015 .SYNOPSIS... GUSTY NORTHEAST WINDS AND HIGH PRESSURE ALOFT WITH BRING CLEAR SKIES AND WELL ABOVE NORMAL TEMPERATURES THROUGH THE WEEKEND. TEMPERATURES WILL RETURN TO NEAR NORMAL NEXT WEEK...WITH LOW PRESSURE SYSTEMS BRINGING A CHANCE OF SHOWERS EARLY IN THE WEEK...THEN AGAIN LATE IN THE WEEK. && .SHORT TERM (TONIGHT-TUE)...STRONG SANTA ANA WIND EVENT TODAY ACROSS LOS ANGELES AND VENTURA COUNTIES CAUSED NUMEROUS DOWNED TREES AND POWER OUTAGES. THE STRONGEST WINDS OCCURRED IN THE LOS ANGELES COUNTY MOUNTAINS AND SANTA MONICAS WITH THE FOLLOWING WIND GUSTS (CAMP NINE AT 79 MPH...MALIBU HILLS AT 77 MPH...MILL CREEK AT 74 MPH). MUCH OF THE LOS ANGELES COUNTY VALLEYS AND EASTERN VENTURA COUNTY VALLEYS WERE ALSO HIT HARD TODAY WITH A PEAK WIND GUST UP TO 60 MPH AT BURBANK...56 MPH AT TONNER CANYON...AND 66 MPH AT CHEESEBORO. MODEL CROSS SECTIONS SHOWED A VERY IMPRESSIVE DEEP LAYER OF STRONG OFFSHORE WINDS AND SUBSIDENCE EARLIER TODAY...ALONG WITH GOOD COLD AIR ADVECTION. THE LAX-DAGGETT GRADIENT PEAKED AT AN IMPRESSIVE -7.5 MB THIS MORNING...AND IS CURRENTLY RUNNING AT -6.6 MB. DUE TO THE STRONG UPPER LEVEL WIND SUPPORT AND SUBSIDENCE BETWEEN 850 AND 500 MB...THE SANTA ANA EVENT WAS MORE WIDESPREAD THAN USUAL...AND STRONG WINDS IN AREAS THAT NORMALLY DO NOT SEE MUCH IN THE WAY OF OFFSHORE WINDS. THIS WOULD INCLUDE AREAS LIKE THE FOOTHILLS OF THE SAN GABRIEL VALLEY...AND MUCH OF THE SAN FERNANDO VALLEY (INCLUDING BURBANK). HIGH WIND WARNINGS REMAIN IN EFFECT THROUGH THIS EVENING FOR THE MOUNTAINS OF LOS ANGELES AND VENTURA COUNTIES (INCLUDING THE SANTA MONICAS) AS WELL AS THE SANTA CLARITA VALLEY...WHERE DAMAGING WIND GUSTS OVER 60 MPH WILL CONTINUE TO BE LIKELY. ONCE THE WIND WARNINGS EXPIRE...WIND ADVISORIES WILL LIKELY BE POSTED THROUGH SUNDAY AFTERNOON FOR THE MOUNTAINS AND SANTA CLARITA VALLEY. WIND ADVISORIES ALSO EXPECTED TO CONTINUE ACROSS MUCH OF THE COASTAL AND VALLEY AREAS...WITH GUSTS GENERALLY RANGING BETWEEN 35 AND 50 MPH. UPPER LEVEL WIND SUPPORT AND SUBSIDENCE WILL GRADUALLY WEAKEN OVERNIGHT INTO SUNDAY AND THE FLOW WILL BECOME MORE EASTERLY WITH TIME. HOWEVER...THERE IS STILL A GOOD SURGE OF OFFSHORE WINDS FROM THE SURFACE TO 850 MB LEVEL LATE TONIGHT INTO SUNDAY MORNING. IN FACT...LAX-DAGGETT GRADIENT EXPECTED TO PEAK AROUND -7 MB ON SUNDAY MORNING. MAX TEMPERATURES CLIMBED INTO THE LOWER 80S TODAY IN WARMER LOCATIONS...AND WILL LIKELY NUDGE UP ANOTHER DEGREE OR TWO ON SUNDAY. MAX TEMPS RECORDS FOR SUNDAY COULD BE IN JEOPARDY IN A FEW LOCATIONS SUCH AS SLO CAL POLY...SBA AIRPORT AND SANTA MARIA AIRPORT...BUT MOST RECORDS ELSEWHERE FOR THE 25TH ARE WELL INTO THE 80S AND WILL PROBABLY BE OUT OF REACH. THE MODERATE TO STRONG SANTA ANA WINDS WILL BRING AN EXTENDED PERIOD OF ELEVATED FIRE DANGER TO SOUTHWEST CALIFORNIA. PLEASE SEE FIRE DISCUSSION BELOW FOR MORE DETAILS. THE UPPER LOW OFF THE BAJA COAST WILL SEND INCREASING MID AND UPPER LEVEL MOISTURE INTO SOUTHERN CALIFORNIA ON MONDAY. THIS SYSTEM IS NOT EXPECTED TO BE A MAJOR RAIN PRODUCER...BUT THERE WILL BE A CHANCE OF RAIN SHOWERS FROM MONDAY AFTERNOON THROUGH TUESDAY. THERE IS STILL THE QUESTION OF HOW MUCH RAIN WILL FALL WITH THIS FIRST SYSTEM...BUT HIGH RESOLUTION NAM MODEL DOES SHOW THE POTENTIAL FOR BETWEEN .10 AND .50 INCHES. .LONG TERM (TUE NIGHT-SAT)...BY TUESDAY NIGHT...ALL EXTENDED MODELS SHOW MOISTURE WITH THE FIRST SYSTEM MOVING OUT OF THE AREA. PARTLY CLOUDY AND COOL ON WEDNESDAY...THEN LONG RANGE MODELS INDICATE ANOTHER SYSTEM FROM THE SOUTHWEST POTENTIALLY MOVING INTO OUR AREA SOMETIME BETWEEN THURSDAY AND FRIDAY. IF ANY RAIN FALLS WITH THIS SYSTEM...IT IS EXPECTED TO BE FAIRLY LIGHT. CONFIDENCE IN THE FORECAST DURING THE ENTIRE LONG TERM PERIOD IS BELOW AVERAGE. && .AVIATION...24/2330Z... THERE IS NO MARINE LAYER AT KLAX THIS AFTERNOON. VFR CONDITIONS EXPECTED ACROSS ALL AIRFIELDS THROUGH PERIOD. GUSTY NORTHEAST WINDS WILL CONTINUE TO DIMINISH GRADUALLY THROUGH THE EVENING HOURS...THEN EXPECTED TO INCREASE SOMEWHAT BY EARLY SUNDAY MORNING. THERE IS STILL THE POTENTIAL FOR LLWS TONIGHT AT KLAX... KBUR...AND KVNY. KLAX...VFR CONDITIONS THROUGH PERIOD LLWS LIKELY ABOVE 020 BETWEEN 25/03-25/09Z. KBUR...VFR CONDITIONS THROUGH PERIOD LLWS LIKELY ABOVE 020 BETWEEN 25/07-25/18Z. && .MARINE...24/300 PM... SMALL CRAFT ADVISORY FOR HAZARDOUS SEA CONDITIONS WAS EXTENDED UNTIL 9 PM THIS EVENING AS A FEW BUOYS WERE STILL SHOWING SWELLS AT OR SLIGHTLY ABOVE 10 FEET THIS AFTERNOON. A WEST TO NORTHWEST SWELL HAD PEAKED LATE THIS MORNING FROM POINT PIEDRAS BLANCAS TO POINT CONCEPTION AS WELL AS IN THE OUTER WATERS SOUTH OF POINT CONCEPTION AND WILL RANGE 7 TO 9 FEET TONIGHT. SMALL CRAFT ADVISORY CONDITIONS FOR NORTHEAST WINDS FROM VENTURA TO SANTA MONICA AND OUT TO THE NORTHERN CHANNEL ISLANDS AS WELL AS THE SAN PEDRO CHANNEL TO AVALON HARBOR WILL NOW BE EXTENDED THROUGH SUNDAY MORNING AS MODELS CONTINUE TO SHOW GUSTY NORTHEAST TO EAST WINDS AFFECTING PORTIONS OF THE INNER WATERS. A LOW PRESSURE SYSTEM OVER THE WESTERN PACIFIC WAS GENERATING SEAS APPROXIMATELY 35 FEET WITHIN A 300-310 DEGREE FETCH DIRECTION. THIS SWELL IS EXPECTED TO ARRIVE BEGINNING NEXT WEEK THURSDAY. && .FIRE WEATHER...24/300 PM... EXTENDED PERIOD OF ELEVATED FIRE DANGER FOR SOUTHERN CALIFORNIA THIS WEEKEND DUE TO MODERATE TO STRONG SANTA ANA WINDS...WARM TEMPERATURES...AND LOW HUMIDITIES. MINIMUM HUMIDITIES HAVE GENERALLY RANGED BETWEEN 10 AND 20 PERCENT ACROSS MUCH OF LOS ANGELES AND VENTURA COUNTIES TODAY...RISING TO BETWEEN 15 AND 30 PERCENT ON SUNDAY. WHILE THE STRENGTH OF SANTA ANA WINDS AND LOW HUMIDITIES WILL LIKELY EXCEED CRITICAL LEVELS IN SOME AREAS TODAY...A RED FLAG WARNING WILL LIKELY NOT BE ISSUED FOR THIS EVENT DUE TO THE CURRENT STATE OF THE FUELS. LIVE FUEL MOISTURE LEVELS HAVE INCREASED SIGNIFICANTLY ACROSS MUCH OF LOS ANGELES AND VENTURA COUNTIES...WHILE GREEN-UP OF THE FINE FUELS HAS BEEN CONSIDERABLE. && .LOX WATCHES/WARNINGS/ADVISORIES... HIGH WIND WARNING (SEE LAXNPWLOX). WIND ADVISORY (SEE LAXNPWLOX). SMALL CRAFT ADVISORY (SEE LAXMWWLOX). HIGH SURF ADVISORY (SEE LAXCFWLOX). HIGH RIP CURRENT RISK (SEE LAXSRFLOX). && $$ PUBLIC...GOMBERG AVIATION/MARINE...30 FIRE...GOMBERG SYNOPSIS...SUKUP WWW.WEATHER.GOV/LOSANGELES

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