Re: WET PATTERN EXPECTED THURSDAY THROUGH SUNDAY

AREA FORECAST DISCUSSION
FXUS66 KLOX 212349 AAA
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
350 PM PST WED FEB 21 2007

UPDATED AVIATION DISCUSSION

.SHORT TERM...THE MAIN WEATHER STORY WILL BE THE TROUGH PUSHING
TOWARD THE AREA TONIGHT AND THURSDAY. TODAY`S MODELS ARE A LITTLE
SLOWER WITH THE STORM THAN YESTERDAY BY NEARLY 6 HOURS. THE ARRIVAL
TIME OF THE SIGNIFICANT RAINFALL ASSOCIATED NOW LOOKS TO HIT THE
NORTHERN PORTION OF OUR AREA BY AROUND NOON THURSDAY. THE FRONT WILL
THEN PUSH INTO THE LOS ANGELES AREA BY EARLY EVENING THURSDAY. THE
FORECAST TIMING MAY NEED TO GET PUSHED BACK ACCORDINGLY. THE LATEST
MODELS ARE ALSO IN GOOD AGREEMENT THAT RAINFALL TOTALS MAY NOT BE
QUITE AS HIGH AS EARLIER INDICATED...ALTHOUGH PRETTY DARN CLOSE. THE
LATEST GUIDANCE STILL SHOWS SOME LOW LEVEL SOUTHERLY FLOW OUT AHEAD
OF THE FRONT WHICH WILL CAUSE A PERIOD OF ENHANCED OROGRAPHIC
PRECIPITATION FOR SOUTH FACING SLOPES. WITH SLOWER TIMING OF THE
STORM...THE COLD AIR MAY NOT ARRIVE UNTIL SOMETIME THURSDAY
NIGHT...SO THE WINTER STORM WATCH MAY NEED TO BE ADJUSTED TO A
SLIGHTLY LATER PERIOD SUCH AS THURSDAY EVENING OR NIGHT. THURSDAY
NIGHT INTO EARLY FRIDAY MORNING IS THE FAVORED TIME FOR WINTER
DRIVING CONDITIONS...INCLUDING MODERATE SNOW...GUSTY WINDS AND COLD
TEMPERATURES IN THE MOUNTAINS. SNOW LEVELS WILL START AT 6000 FEET
LATE THURSDAY AFTERNOON AND LOWER TO 4000 FEET BY EARLY FRIDAY
MORNING. THEREFORE...THE INTERSTATE 5 CORRIDOR WILL BE VULNERABLE TO
WINTER DRIVING CONDITIONS LATE THURSDAY NIGHT INTO FRIDAY MORNING.
ANOTHER CONSIDERATION FOR THE WINTER STORM WATCH IS THE RATHER FAST
MOVEMENT OF THE SYSTEM WHICH COULD LIMIT THE SNOWFALL
TOTALS...ALTHOUGH THE STRENGTH OF THE SYSTEM COULD STILL OVERWHELM A
SHORTER PRECIPITATION DURATION. AT LOWER ELEVATIONS...RAINFALL
TOTALS FOR THE STORM SHOULD RANGE FROM ABOUT ONE HALF INCH TO NEARLY
ONE AND ONE HALF INCHES. OROGRAPHIC ENHANCEMENT WITH THE STORM WILL
BRING TOTALS IN THE MOUNTAINS TO 1 TO 3 INCHES OF LIQUID
PRECIPITATION.

FRIDAY WILL BE COLD AND SHOWERY WITH A THREAT OF THUNDERSTORMS IN
UNSTABLE AIR. TEMPERATURES WILL BE A GOOD 10 TO 15 DEGREES BELOW
NORMAL. ADDITIONAL ACCUMULATIONS ARE POSSIBLE.

.LONG TERM...THE WEEKEND WILL SHOW SOME RECOVERY IN TEMPERATURES
UNDER MOSTLY CLEAR SKIES AND NORTHWEST FLOW ALOFT. THE NEXT TROUGH
IN THE SERIES WILL ATEMPT TO BRING RAIN DOWN TO THE NORTHERN
PORTIONS OF THE FORECAST AREA TUESDAY AFTERNOON...HOWEVER RAINFALL
AMOUNTS WILL BE MUCH LIGHTER WITH THIS NEXT TROUGH DUE TO A MORE
INLAND TRAJECTORY.

&&

.AVIATION...21/2350Z
STRATUS SURGING TOWARD SHORE THIS AFTERNOON. AIRFIELDS NORTH OF KOXR
WILL BE UNDER MVFR/VFR CIGS THROUGH THIS EVENING. OTHER AIRFIELDS
WILL DODGE CIGS FOR THE TIME BEING...BUT WILL BE PRIMED FOR AN
EARLIER RETURN OF STRATUS THAN PREVIOUSLY THOUGHT. CIGS WILL BE ON
THE HIGH SIDE THROUGH THE NIGHT...WITH MVFR ABOVE 020 THE WORST THAT
SHOULD BE EXPECTED. MARINE LAYER WILL WEAKEN LATER TONIGHT...BUT
MOISTURE FROM APPROACHING SYSTEM WILL KEEP MOSTLY VFR CIGS AROUND.
RAIN WILL BEGIN NORTH OF KSBA AFTER 14Z...WITH THE MAIN BAND NEAR
KPRB BY 17Z.

KLAX WILL CONTINUE TO SEE A WESTERLY SEABREEZE THROUGH ABOUT 04Z.
CIGS SHOULD RETURN EARLIER...AROUND 06Z...WITH A WINDOW BETWEEN 03Z
AND 08Z. CIGS SHOULD STAY ABOVE 020...AND GO ABOVE 030 JUST AFTER
SUNRISE. RAIN SHOULD NOT BEGIN THU UNTIL AFTER 20Z.

KBUR WILL SEE MVFR CIGS AND VIS AFTER 07Z...WITH A WINDOW OF ONSET
BETWEEN 06Z AND 10Z.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH (SEE LAXWSWLOX).
SMALL CRAFT ADVISORY (SEE LAXCWFLOX).

&&

PUBLIC...SWEET
AVIATION...KITTELL