Area Forecast Discussion
Issued by NWS Los Angeles, CA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS66 KLOX 301747
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1045 AM PDT TUE JUN 30 2015

.SYNOPSIS...
A WARM AND HUMID AIR MASS WILL CONTINUE OVER THE AREA THROUGHOUT THE
WEEK AS HIGH PRESSURE REMAINS OVER THE GREAT BASIN. SOUTHEAST FLOW
ALOFT...MOIST AND UNSTABLE AIR WILL CONTINUE A SLIGHT CHANCE OF
THUNDERSTORMS AND SHOWER OVER THE MOUNTAINS AND DESERTS. A COOLING
TREND IS EXPECTED TOWARD THE WEEKEND AS LOW PRESSURE APPROACHES.

&&

.SHORT TERM (TODAY-FRI)...FAVORABLE SOUTHEAST FLOW WILL CONTINUE
THROUGH THE END OF THE WEEK. TODAY MAY BE THE BEST DAY FOR
MTN/DESERT THUNDERSTORMS AS MODELS SHOW THE BEST COMBO OF MOISTURE
(THOUGH NOT TOO MUCH CLOUDS SO AS TO INHIBIT CONVECTION) AND
INSTABILITY. BY TONIGHT AND WEDNESDAY THAT LARGE MASS OF CLOUDS OVER
NRN MEXICO WILL BE MOVING INTO THE AREA, AND WHILE PWATS WILL
INCREASE TO AROUND 1.5", THERE WILL LIKELY BE CONSIDERABLE
CLOUDINESS ASSOCIATED WITH THAT WHICH WILL GREATLY INHIBIT
CONVECTION. A MORE PROBABLE SCENARIO FOR TONIGHT AND WEDNESDAY WOULD
BE A LOT OF CLOUDS AND SOME ISOLATED SPRINKLES OR LIGHT SHOWERS
ACROSS THE SOUTHERN HALF OF THE FORECAST AREA, MAINLY SOUTH OF SLO
COUNTY, BUT NO THUNDER. COULD BE A SIMILAR DAY AS LAST SATURDAY.

ANOTHER WARM TODAY UNDER AMPLE SUNSHINE AND FAIRLY WEAK ONSHORE
FLOW. IF MOISTURE AND CLOUDS INCREASE TONIGHT AS EXPECTED LOOK FOR
QUITE A DROP IN TEMPS WEDNESDAY THOUGH MUCH HIGHER HUMIDITIES.

MODELS INDICATE A DRIER AIR MASS THURSDAY SO MORE SUN AND WARMER
TEMPS. THEN TURNING COOLER FRIDAY AS ONSHORE FLOW STRENGTHENS. NOT
MUCH INSTABILITY EITHER DAY SO IT DOESN`T LOOK LIKE A PARTICULARLY
FAVORABLE THUNDERSTORM SITUATION.

***FROM PREVIOUS DISCUSSION***

.LONG TERM (SAT-MON)... THE UPPER HIGH PUSHES OFF TO THE EAST
SATURDAY AND DRIER COOLER SW FLOW SETS UP OVER THE AREA. THIS WILL
END THE CHANCE OF AFTERNOON CONVECTION. THE MARINE LAYER STRATUS
WILL COVER MORE AND MORE OF THE COAST EACH DAY BUT WILL LIKELY NOT
MAKE IT INTO THE VLYS. AS THE MARINE LAYER INCREASES AND HGTS FALL A
COOLING TREND WILL SET IN AND MAX TEMPS WILL COOL A DEGREE OR TWO
EACH DAY.

&&

.AVIATION...30/1800Z...

MID/UPPER LEVEL RIDGE OF HIGH PRESSURE CENTERED OVER THE FOUR
CORNERS AREA AND TROUGH OF LOW PRESSURE SOUTHWEST OF THE AREA WILL
PERSIST. MID/UPPER LEVEL LIGHT/MODERATE SOUTHEAST WINDS WILL PREVAIL
OVER THE AREA. ISOLATED TSTMS OVER THE MOUNTAINS FROM SANTA BARBARA
COUNTY TO LA COUNTY THROUGH 01/03Z AND AFTER 01/20Z. TSTMS WITH TOPS
40KFT WILL MOVE NORTHWEST APPROXIMATELY 25KT. BASE OF THE MARINE
LAYER INVERSION WAS AROUND .9FT THIS MORNING OVER KLAX AND WILL
CHANGE LITTLE.

MARINE LAYER AT LAX AT 1600Z IS 910 FEET DEEP AND THE INVERSION TOP
IS AT 4323 FEET WITH A TEMP OF 26.2 DEGREES C.

KLAX...CHANCE CIGS 009 BETWEEN 01/13-01/17Z OTHERWISE CURRENT
SKY/VSBY CONDITIONS LIKELY.

KBUR...CURRENT SKY/VSBY LIKELY THROUGH THE PERIOD.

VIRTUALLY CERTAIN - 95-100%
VERY LIKELY       - 80-95%
LIKELY            - 60-80%
CHANCE            - 30-60%
VERY UNLIKELY     - 20% OR LESS

&&

.MARINE...30/900 AM.

SMALL CRAFT ADVISORY CONDITIONS ARE NOT EXPECTED THROUGH FRIDAY
MORNING. THERE IS A CHANCE SCA CONDITIONS WITH WEST WINDS WILL EXIST
OVER THE SANTA BARBARA AND SANTA CRUZ BASINS FRIDAY AND SATURDAY
AFTERNOON. OTHERWISE A GALE TO STORM FORCE WIND FETCH IN THE
VICINITY NEW ZEALAND SOUTH ISLAND THIS MORNING WILL GRADUALLY SHIFT
EAST. WHILE THE STORM SYSTEM SHIFTS EAST THE WINDS ARE EXPECTED TO
WEAKEN AND GALE FORCE WINDS WILL PREVAIL THROUGH WEDNESDAY MORNING.
THE FETCH IS ORIENTED 200-220 DEGREES RELATIVE TO VENTURA COUNTY.
THE SWELLS WILL BEGIN TO ARRIVE MONDAY MORNING AND BUILD THROUGH
TUESDAY.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
NONE

&&

$$

PUBLIC...MW/RORKE
AVIATION/MARINE...30
SYNOPSIS...BARTLING

WWW.WEATHER.GOV/LOSANGELES


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.