004  
FXUS66 KLOX 191018  
AFDLOX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA  
318 AM PDT MON MAY 19 2025  
   
SYNOPSIS
 
19/201 AM.  
 
A RIDGE OF HIGH PRESSURE WILL RESULT IN AN EXTENDED PERIOD OF VERY  
HOT WEATHER THIS WEEK, PEAKING ON WEDNESDAY AND THURSDAY. HIGH  
TEMPERATURES WILL BE WELL ABOVE NORMAL. GUSTY WINDS ARE EXPECTED  
ACROSS SOUTHERN SANTA BARBARA COUNTY AND IN THE LOS ANGELES COUNTY  
MOUNTAINS NEAR THE GRAPEVINE.  
 

 
   
SHORT TERM (TDY-WED)
 
19/315 AM.  
 
A RIDGE IS BEGINNING TO MOVE INTO THE STATE AND HGTS WILL RISE TO  
582 DAM BY THE AFTERNOON. CURRENTLY THERE IS WEAK ONSHORE FLOW TO  
THE EAST AND WEAK OFFSHORE FLOW FROM THE NORTH. THERE ARE NO  
MARINE LAYER CLOUDS ALTHOUGH SOME CLOUDS MAY FORM NEAR LONG BEACH  
AROUND SUNRISE. THE AFTERNOON PRESSURE GRADIENTS WILL REMAIN  
SLIGHTLY ONSHORE TO THE EAST AND SLIGHTLY OFFSHORE FROM THE  
NORTH. RISING HGTS AND THE WEAK PRESSURE GRADS WILL TEAM UP WITH  
THE TOTALLY SUNNY SKIES TO BRING 3 TO 6 DEGREES OF WARMING TO THE  
COASTS AND 6 TO 12 LOCALLY 15 DEGREES OVER THE REST OF THE AREA.  
MOST MAX TEMPS WILL END UP 4 TO 8 DEGREES ABOVE NORMAL. THERE WILL  
BE ANOTHER ROUND OF SUNDOWNER WINDS ACROSS THE SBA SOUTH COAST  
TONIGHT.  
 
THE RIDGE FLATTENS OUT ON TUESDAY BUT HGTS REMAIN AT 582 DAM.  
THERE SHOULD BE OFFSHORE FLOW FROM BOTH THE NORTH AND THE EAST IN  
THE MORNING ALTHOUGH THE E/W GRADIENT WILL TURN ONSHORE IN THE  
AFTERNOON. THE AIRMASS WILL CONTINUE TO WARM UNDER CLOUD FREE  
SKIES. MOST OF SLO AND SBA COUNTIES WILL ONLY WARM 1 OR 2  
DEGREES. VTA AND LA COUNTIES, HOWEVER, WILL SEE ANOTHER 4 TO 8  
DEGREES OF WARMING AS THE OFFSHORE FLOW WILL HAVE THE GREATEST  
AFFECT IN THIS LOCATION. MAX TEMPS ACROSS THE CSTS WILL BE IN THE  
70S EXCEPT THE INTERIOR PORTIONS OF THE LA/VTA CSTS WHERE LOWER  
TO MID 80S WILL BE COMMON. THE VLYS WILL SEE MAX TEMPS IN THE  
90S. THESE TEMPS WILL BE CLOSE TO ADVISORY CRITERIA BUT JUST  
UNDER. STILL, PEOPLE WORKING OR PLAYING OUTSIDE IN THE VLYS  
SHOULD BE AWARE OF HEAT DANGERS.  
 
.THE HOTTEST DAYS (WED-THU)  
 
ANOTHER LITTLE RIDGE MOVES INTO THE STATE ON WEDNESDAY AND HGTS  
WILL PEAK AT 595 DAM. THERE WILL NOT BE MUCH CHANGE WITH THE  
GRADIENTS WHICH WILL BE WEAK. WEDNESDAY WILL BE THE HOTTEST DAY.  
THE VLYS WILL SEE MAX TEMPS FROM 95 TO 103 DEGREES (15 TO 20  
DEGREES ABOVE NORMAL). IN ADDITION THERE WILL BE A VERY STRONG  
INVERSION AROUND 1000 FT (RIGHT AT MANY VLY ELEVATIONS) AND THIS  
WILL KEEP MANY OVERNIGHT LOWS WELL ABOVE NORMAL. WARMER THAN  
NORMAL HIGHS AND LOWS WILL COMBINE TO BRING MODERATELY DANGEROUS  
HEAT CONDITIONS TO THE VLYS AND LOWER MTN ELEVATIONS.  
 
THURSDAY WILL BE A LITTLE COOLER AS SLIGHTLY LOWER HGTS AND  
SLIGHTLY STRONGER ONSHORE FLOW ARRIVES, BUT IT WILL NOT BE ENOUGH  
TO REDUCE THE HEAT DANGER. THERE MAY EVEN BE SOME SHALLOW MARINE  
LAYER CLOUDS AT THE BEACHES WITH DENSE FOG IN THE MORNING. THERE  
WILL BE STRONGER ONSHORE FLOW TO THE EAST AND THIS WILL MAKE THE  
BEACH TEMPERATURE FORECAST TRICKY AS THERE COULD BE A HUGE TEMP  
GRADIENT BETWEEN THE BEACHES AND THE INLAND AREAS.  
 
PEOPLE PLANNING OUTDOOR ACTIVITIES FOR THIS TWO DAY PERIOD SHOULD  
TAKE PRECAUTIONS TO AVOID HEAT RELATED DANGERS.  
   
LONG TERM (FRI-SUN)
 
19/1204 AM.  
 
GOOD MDL AGREEMENT THAT A TROF WILL RIPPLE THROUGH THE STATE ON  
FRIDAY. HGTS WILL NOT FALL TOO MUCH ONLY ABOUT 2 DAM. MORE  
IMPORTANTLY THERE WILL BE STRONG ONSHORE TRENDS LEADING TO MDT TO  
STG ONSHORE FLOW BOTH TO THE NORTH AND EAST IN THE AFTERNOON. THE  
INCREASED ONSHORE FLOW AND CYCLONIC TURNING ALOFT WILL PRODUCE AN  
ABUNDANCE OF MORNING LOW CLOUDS THAT WILL COVER MOST OF THE CSTS  
AND SOME OF THE LOWER VLYS. ALMOST ALL AREAS WILL SEE 3 TO 6  
DEGREES OF COOLING. STILL WITH CSTL HIGHS MOSTLY IN THE MID 70S TO  
LOWER 80S AND THE VLYS COMING IN THE UPPER 80S TO LOWER 90S, MAX  
TEMPS WILL REMAIN WELL ABOVE NORMAL.  
 
THE REAL COOLING WILL HIT SATURDAY AS HGTS FALL AND ONSHORE FLOW  
REMAINS STRONG. COASTAL LOW CLOUDS ARE LIKELY ALTHOUGH MANY  
ENSEMBLES SHOW SLIGHTLY LESS COVERAGE THAN ON FRIDAY. THE BIG NEWS  
WILL BE THE TEMPS: LOOK FOR 5 TO 10 LOCALLY 12 DEGREES ACROSS THE  
AREA. THE BIGGEST COOLING WILL OCCUR IN THE LA/VTA VLYS. MAX TEMPS  
WILL DROP TO A FEW DEGREES EITHER SIDE OF NORMAL.  
 
SLIGHTLY HIGHER HGTS AND SLIGHTLY LESS ONSHORE FLOW WILL BRING A  
FEW DEGREES OF WARMING TO THE AREA ON SUNDAY.  
 

 
   
AVIATION
 
19/0958Z.  
 
AROUND 0930Z, THE MARINE LAYER DEPTH WAS AROUND 1000 FEET DEEP AT  
KLAX. THE TOP OF THE WEAK INVERSION WAS 3000 FEET WITH A  
TEMPERATURE NEAR 16 DEGREES CELSIUS.  
 
MODERATE CONFIDENCE IN THE CURRENT FORECAST FOR LOS ANGELES COUNTY  
COASTAL TERMINALS, OTHERWISE HIGH CONFIDENCE EXISTS. THERE IS A  
LOW-TO-MODERATE CHANCE OF IFR TO MVFR CONDITIONS BETWEEN 13Z AND  
16Z. OTHERWISE, VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD.  
 
KLAX...THERE IS A 30 PERCENT CHANCE OF IFR TO MVFR CONDITIONS  
BETWEEN 13Z AND 16Z. OTHERWISE, VFR CONDITIONS ARE EXPECTED  
THROUGH THE PERIOD. NO SIGNIFICANT EAST WIND COMPONENT IS EXPECTED  
AT THIS TIME.  
 
KBUR...VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. NO WIND  
IMPACTS ARE EXPECTED AT THIS TIME.  
 

 
   
MARINE
 
19/311 AM.  
 
MODERATE TO HIGH CONFIDENCE IN THE CURRENT FORECAST. HIGHER  
CONFIDENCE EXISTS IN THE FORECAST FOR SEAS RELATIVE TO THE  
FORECAST FOR WINDS.  
 
FOR THE OUTER WATERS AND THE NEARSHORE WATERS ALONG THE CENTRAL  
COAST, THERE IS A 80-100 PERCENT OF SMALL CRAFT ADVISORY (SCA)  
CONDITIONS THROUGH TUESDAY NIGHT, EXCEPT FOR LULLS NEARSHORE ALONG  
THE CENTRAL COAST DURING LATE NIGHT AND EARLY MORNING HOURS.  
THERE IS A 60-90 PERCENT CHANCE FOR GALE FORCE WINDS THIS  
AFTERNOON THROUGH THIS EVENING, DECREASING TO A 50-80 PERCENT  
CHANCE FROM EARLY TUESDAY THROUGH TUESDAY NIGHT. THERE COULD BE A  
BRIEF DECREASE TO SCA LEVELS IN THE CENTRAL AND SOUTHERN ZONE  
POSSIBLE MONDAY MORNING. THE HIGHEST CHANCES WILL BE FOR THE  
MAJORITY OF THE OUTER WATERS, WHILE THE LOWEST CHANCES WILL BE FOR  
THE NEARSHORE WATERS ALONG THE CENTRAL COAST AND THE FOR SOUTHERN  
OUTER WATERS. THERE REMAINS A MODERATE TO HIGH CHANCE FOR GALE  
FORCE WINDS THROUGH THE WORK WEEK, BUT LOW CONFIDENCE IN TIMING  
AND MAX WIND SPEEDS EXISTS BEYOND TUESDAY.  
 
IN THE SANTA BARBARA CHANNEL, THERE IS A 50-70 PERCENT CHANCE OF  
SCA LEVEL WINDS THROUGH THIS AFTERNOON AND TONIGHT, FOLLOWED BY A  
40-60 PERCENT CHANCE ON TUESDAY AFTERNOON AND NIGHT. THE HIGHEST  
CHANCES ARE FOR THE WESTERN PORTION OF THE SANTA BARBARA CHANNEL,  
WHILE THE LOWEST IS FOR THE EASTERN PORTION OF THE SANTA BARBARA  
CHANNEL. THERE ARE LESSER CHANCES FOR WEDNESDAY AND THURSDAY  
AFTERNOONS AND EVENINGS.  
 
SOUTH OF POINT MUGU, INTO THE SANTA MONICA BAY AND THE SAN PEDRO  
CHANNEL. WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW SCA LEVELS  
IN THE SOUTHERN INNER WATERS, BUT THERE IS A MODERATE CHANCE OF  
SCA LEVEL WINDS GUSTS BRIEFLY FROM POINT DUME TO PACIFIC PALISADES  
THIS AFTERNOON AND EVENING.  
 

 
   
LOX WATCHES/WARNINGS/ADVISORIES
 
 
CA...WIND ADVISORY REMAINS IN EFFECT UNTIL 6 AM PDT EARLY THIS  
MORNING FOR ZONES 349-351. (SEE LAXNPWLOX).  
WIND ADVISORY REMAINS IN EFFECT UNTIL 10 AM PDT THIS MORNING  
FOR ZONES 352-353-376>378. (SEE LAXNPWLOX).  
PZ...SMALL CRAFT ADVISORY IN EFFECT UNTIL 3 PM PDT THIS AFTERNOON  
FOR ZONE 645. (SEE LAXMWWLOX).  
GALE WARNING IN EFFECT FROM 3 PM THIS AFTERNOON TO 9 PM PDT  
THIS EVENING FOR ZONE 645. (SEE LAXMWWLOX).  
GALE WATCH IN EFFECT FROM TUESDAY AFTERNOON THROUGH TUESDAY  
EVENING FOR ZONE 645. (SEE LAXMWWLOX).  
SMALL CRAFT ADVISORY IN EFFECT FROM 3 PM THIS AFTERNOON TO 3  
AM PDT TUESDAY FOR ZONE 650. (SEE LAXMWWLOX).  
GALE WARNING IN EFFECT UNTIL 3 AM PDT WEDNESDAY FOR ZONES  
670-673-676. (SEE LAXMWWLOX).  
 

 
 

 
 
PUBLIC...RORKE  
AVIATION...HALL  
MARINE...HALL  
SYNOPSIS...KL/CILIBERTI  
 
WEATHER.GOV/LOSANGELES  
 
EXPERIMENTAL GRAPHICAL HAZARDOUS WEATHER OUTLOOK AT:  
HTTPS://WWW.WEATHER.GOV/ERH/GHWO?WFO=LOX  
 
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