FXUS66 KHNX 071222
AFDHNX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
422 AM PST MON DEC 7 2009

.SYNOPSIS...
A COLD LOW PRESSURE SYSTEM WILL MOVE OVER THE AREA THROUGH TONIGHT. 
THIS SYSTEM WILL BRING RAIN AND LOW ELEVATION SNOW. AFTER A COUPLE 
OF DAYS WITH DRY CONDITIONS MORE WET WEATHER IS EXPECTED OVER THE 
AREA WEDNESDAY NIGHT THROUGH THE FOLLOWING WEEKEND DUE TO A TROUGH 
PATTERN.

&&

.DISCUSSION...
THE COLD UPPER TROF IS MAKING ITSELF FELT ACROSS CENTRAL CA NOW.
SAT PIX SHOW THE CENTER OF THE UPPER LOW OVER NORCAL AND MOVING
SE. THE ASSOCIATED ARCTIC FRONT IS MOVING SOUTH ALONG THE COAST
AND IS NEARING THE NORTH BAY AREA. IT WILL CONT TO SWEEP SOUTH AND
EAST DURING THE DAY WITH SHARPLY LOWERING SNOW LEVELS. MADE A FEW
MINOR TWEEKS TO THE WSW BUT OVERALL THE PREV FCST LOOKED FINE.
REMOVED THE CENTRAL SJV FROM IT THOUGH...AS SNOW ON THE VALLEY
FLOOR LOOKS HIGHLY UNLIKELY UNLESS A FEW SNOW FLAKES MIX IN WITH
THE RAIN WITH THE FRONT. ADDITIONALLY THERE WILL NOT BE THE
STRONG WINDS ASSOCIATED WITH THE PREVIOUS WINTER WX ADVISORY.

THIS SYSTEM WILL MOVE QUICKLY EAST...AND BE OUT OF CENTRAL CA
LATER THIS EVE. IN ITS WAKE WILL BE COLDER TEMPS...WITH THE USUAL
LOW CLOUDS ON THE EAST SIDE AND SOUTH END OF THE VALLEY AND
ADJACENT FOOTHILLS. HOWEVER...WHEREVER CLOUDS DISSIPATE TONIGHT
TEMPS WILL TUMBLE INTO THE 20S AND HAVE UPGRADED THE FREEZE WATCH
FOR THE VALLEY TO A WARNING. CLEAR TO PARTLY CLOUDY SKIES TUES
NIGHT WILL BRING A FREEZE ONCE AGAIN...WITH TEMPS AT OR SLIGHTLY
LOWER THAN THOSE OF TONITE.

DRY BUT COOL WX WILL DOMINATE THRU AT LEAST WED...AND PROBABLY
THURS. IN THE MEDIUM RANGE...MODELS ARE HAVING THE USUAL
DIFICULTIES IN WHEN OR HOW STRONG TO BRING UNDERCUTTING SOUTHERN
STREAM SHORTWAVE TROFS TO THE COAST. THE EURO HOLDS OFF ON ANY
PRECIP UNTIL THURS OR THURS NITE WITH ON-AGAIN/OFF-AGAIN PRECIP
INTO THE WEEKEND. BASICALLY KEPT A CHANCE OF PRECIP THROUGHOUT AND
NOT AS COLD. CONFIDENCE IN ANY GIVEN MODEL FEATURE OR WHICH DAY IS
PRETTY LOW.

&&

.AVIATION...
A COLD STORM SYSTEM TRACKING THROUGH THE REGION WILL SPREAD 
INCREASING AREAS OF MVFR AND LOCAL IFR CONDITIONS IN RAIN AND SNOW 
ACROSS THE CENTRAL CALIFORNIA THROUGH 08Z TUESDAY...THEN
CONDITIONS ARE EXPECTED TO BEGIN SLOWLY IMPROVING BETWEEN 08Z
TUESDAY AND 12Z TUESDAY. FREEZING AND/OR FROZEN PRECIPITATION
COULD FALL AS LOW AS THE VALLEY FLOOR IN THE MERCED AREA BY THIS
AFTERNOON.

&&

.AIR QUALITY ISSUES...
NONE

&&

.HNX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL MIDNIGHT PST TONIGHT FOR CAZ093>097.

FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM PST TUESDAY FOR 
CAZ089>092.

FREEZE WARNING FROM 10 PM TUESDAY TO 9 AM PST WEDNESDAY FOR 
CAZ089>092.

&&

$$

PUBLIC...BINGHAM
AVN/FW...DS
SYNOPSIS...BSO

WEATHER.GOV/HANFORD