000
FXUS66 KHNX 052253
AFDHNX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
253 PM PST SAT DEC 5 2009
.SYNOPSIS...ONE MORE DAY OF MILD DAYTIME TEMPERATURES AND PARTLY
CLOUDY SKIES. RAIN...HIGHER ELEVATION SNOW...GUSTY WINDS AND MUCH
COLDER TEMPERATURES ARE IN STORE FOR THE MUCH OF THE UPCOMING
WEEK.
&&
.DISCUSSION...WATER VAPOR SATELLITE IMAGERY SHOWING THE SURGE OF
COLDER AIR NOW ONTO THE WEST COAST WITH A STORM HEADED TOWARD
CENTRAL CALIFORNIA. WHILE CENTRAL CALIFORNIA HAD ANOTHER MOSTLY
SUNNY DAY WITH TEMPERATURES REACHING INTO THE 60S...A CHANGE IN
THE WEATHER WILL START IN JUST BEYOND 24 HOURS.
A A VORT MAX LOBE DID PASS OVER THE REGION TODAY...PRODUCING
STRONG WINDS SOME LOCATIONS IN THE VALLEY WERE SHOWING GUSTS UP TO
25 MPH. WHILE THESE WINDS WILL SUBSIDE OVERNIGHT...THE MAIN AREA
OF ENERGY START BEING FELT SUNDAY AFTERNOON AS STRONG WINDS WILL
BE SEEN AHEAD OF THE DISTURBANCE. WILL SEE MUCH STRONGER WINDS AS
SOME MOUNTAIN LOCATIONS COULD SEE WIND GUSTS UP TO 60 MPH.
MODELS STILL INDICATING THE DISTURBANCE MAY RETROGRADES MORE
OFFSHORE AS IT DROPS SOUTH...AND PICK UP A GOOD FETCH OF MOISTURE
FOR HEAVY SNOW OVER THE MOUNTAINS. ALONG WITH HEAVY SNOW...STRONG
WINDS AND COLD AIR WILL BE THE MAIN ISSUES WITH THIS STORM.
MODELS STILL PROGGING VERY COLD AIR PUSHING INTO THE AREA ON
MONDAY. THIS COLD AIR COULD LEAD TO SNOW LEVELS DOWN TO THE
FOOTHILLS OF THE SIERRA NEVADA AT AROUND 1500 FEET AND NEAR 4000
FEET (GRAPEVINE) IN THE KERN MOUNTAINS. THIS SNOW LEVELS ARE
SUPPORTED BY 700MB TEMPS OF -14 DEG-C NEAR YOSEMITE AND -8 DEG-C
NEAR FRAZIER PARK...ALONG WITH 1000-500MB THICKNESS VALUES OF 5300
TO 5400 METERS...RESPECTIVELY. ALONG WITH THE WINTER STORM WATCH
FOR POSSIBLE SNOW FALL FROM YOSEMITE TO THE GRAPEVINE. COLD AIR
WILL FILTER INTO THE SAN JOAQUIN VALLEY MONDAY NIGHT. WILL ALSO
ISSUE A FREEZE WATCH FOR THE SAN JOAQUIN BETWEEN LATE MONDAY NIGHT
TO TUESDAY MORNING BEFORE THE NEXT STORM HITS CENTRAL CALIFORNIA.
WHILE TUESDAY MAY SEE A BRIEF STOP IN UNSETTLED CONDITIONS...MODELS
THEN INTRODUCE THE NEXT IN THE SERIES OF STORMS MOVING THROUGH
CALIFORNIA. THE SECOND STORM SHOWS MORE OF A WESTERLY TRAJECTORY
PUSHING IN FROM THE EASTERN PACIFIC. CURRENT TIMING HAS THIS NEXT
STORM PUSHING INTO THE AREA LATER ON WEDNESDAY AND AIMING FOR
CENTRAL CALIFORNIA. MODELS SHOW THIS TROF HAVING A GOOD FETCH
EXTENDING OUT BEYOND 130W WITH THE POTENTIAL FOR SIGNIFICANT
PRECIP DURING THE EVENT. THIS SECOND STORM WILL BE A WARMER ONE
WITH SNOW LEVEL RISING TO NEAR 5000 FEET NEAR YOSEMITE BUT DROP
MORE SNOW THEN THE FIRST STORM. MODELS THEN SHOW LITTLE CHANGE IN
THE PATTERN TOWARD THE END OF THE WEEK AS THE DISTRICT CONTINUES
UNDER A CYCLONIC FLOW PATTERN. THEREFORE...MAY CONTINUE THE THREAT
OF PRECIP INTO THE WEEKEND FOR ADDITIONAL ACCUMULATION OF RAIN
AND SNOW.
&&
.AVIATION...IN THE SAN JOAQUIN VALLEY...EXPECT WIDESPREAD MVFR
AND SOME LINGERING LCL IFR VISIBILITIES IN HAZE AND MIST THROUGH
06Z SUNDAY. AREAS OF IFR AND LCL LIFR IN BR/FG REDEVELOPING 06Z-
18Z SUNDAY. OTHERWISE...VFR CONDITIONS WILL PREVAIL ACROSS THE
CENTRAL CALIFORNIA INTERIOR THROUGH 00Z MONDAY.
&&
.AIR QUALITY ISSUES...ON SUNDAY DECEMBER 6 2009...
UNHEALTHY FOR SENSITIVE GROUPS IN FRESNO...KERN...KINGS...MADERA
AND TULARE COUNTIES. FIREPLACE/WOOD STOVE BURNING IS PROHIBITED IN
FRESNO...KERN...KINGS...MADERA...MERCED AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.HNX WATCHES/WARNINGS/ADVISORIES...WINTER STORM WATCH FROM LATE
SUNDAY NIGHT THROUGH MONDAY EVENING FOR THE SIERRA NEVADA FROM
YOSEMITE TO KINGS CANYON...THE TULARE COUNTY MOUNTAINS AND THE
KERN COUNTY MOUNTAINS /CAZ095>097/.
FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING FOR
THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY /CAZ089>092/.
&&
$$