FXUS66 KSTO 050600
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
1000 PM PST SAT FEB 4 2012

.SHORT TERM DISCUSSION...

BLOCKING PATTERN OVER THE INTERIOR WRN STATES GAVE INTERIOR NORCAL
ANOTHER SEASONABLY WARM DAY WITH MAX TEMPS ON SAT A FEW DEG WARMER
THAN FRI OVER MOST OF THE AREA. DURING THE DAY ON SUN...HIGH
CLOUDINESS OVER THE ERN PAC WILL SPREAD INLAND...AND THICKEN ON MON.
MINOR SYNOPTIC WARMING WILL LIKELY BE SUPPRESSED BY THICKENING CLOUD
COVER ESPECIALLY ON MON...AHEAD OF AN APPROACHING SPLITTING TROF.
UNTIL THEN...DRY AND STILL SEASONABLY MILD WX WILL CONTINUE WITH
MINIMAL EARLY MORNING FOG.

ENERGY IN THE FORM OF A MODERATELY STRONG CLOSED LOW IS FORECAST TO
SPLIT OFF FROM THE ERN PAC TROF...AND ENCOUNTER RESISTANCE FROM THE
HIGHLY AMPLIFIED RIDGE ALONG THE W COAST. THE GFS/ECMWF/GEM ARE IN
GOOD AGREEMENT OF THE CLOSED LOW DROPPING SEWD AND PARALLELING THE
CA COAST TUE AND WED. RIDGING QUICKLY REBUILDS ALONG THE COAST AS
THE CLOSED LOW MOVES OVER BAJA. THE ASSOCIATED PW PLUME...ALMOST
ORIENTED N TO S ALONG THE CA COAST...IS ALSO FORECAST TO SPLIT ON
TUE. THE TRACK OF THE CLOSED LOW REMAINING OFFSHORE AND THE
SPLITTING PW PLUME DO NOT BODE WELL FOR WIDESPREAD SIGNIFICANT
PRECIP FOR INTERIOR NORCAL. FOR EXAMPLE...THE BUFKIT QPFS RANGE
FROM A .10 INCH AT RDD TO .20 INCH AT BLU TO .30 AT SAC TO .40 AT
SCK TO .80 AT SUU AND AN INCH AT UKI. ONE CAN SEE THAT THE
OFFSHORE TRACK OF THE CLOSED LOW WILL FAVOR HIGHER QPFS OVER THE
FAR WRN AND SRN PORTIONS OF OUR FORECAST AREA IN INTERIOR NORCAL.
LITTLE QPF IS EXPECTED IN THE FAR NRN ZONES AND OVER THE SIERNEV
AS THE MID-LEVEL FLOW WILL PARALLEL THE SIERNEV /NIL-WEAK OROGRAPHICS/.
THUS...THIS SYSTEM WILL NOT HAVE A SIGNIFICANT IMPACT ON NORCAL
RESERVOIRS. JHM

.EXTENDED DISCUSSION (WEDNESDAY THROUGH SATURDAY)

AS THE TUESDAY STORM SYSTEM MOVES SOUTH OF OUR CWA BY EARLY
WEDNESDAY...ANOTHER HIGH AMPLITUDE RIDGE BUILDS INTO NORCAL. THE
ECMWF...GFS...AND GEM MODELS ARE ALL SHOWING GOOD AGREEMENT WITH
THE RIDGE PATTERN FROM WEDNESDAY THROUGH EARLY FRIDAY. THIS WILL
BRING A PERIOD OF ABOVE NORMAL TEMPERATURES AND DRY WEATHER WITH
FAIRLY CLEAR SKIES. ANOTHER STORM SYSTEM APPROACHES THE WEST
COAST ON FRIDAY AND COULD POTENTIALLY BRING SOME LIGHT RAIN TO
INTERIOR NORCAL ON SATURDAY. CONFIDENCE IS NOT HIGH ON THIS SYSTEM
SINCE THE 06Z MODELS HAD VARIED SOLUTIONS, BUT THE 12Z RUNS SHOW
MORE CONSISTENCY. JBB


&&

.AVIATION...

VFR CONDITIONS ARE EXPECTED TO DOMINATE OVER INTERIOR NORCAL FOR
THE NEXT 24 HOURS AS A RIDGE OF HIGH PRESSURE HOLDS IN PLACE
ALONG THE WEST COAST. ONLY EXCEPTION IS THE POSSIBILITY OF PATCHY FOG
WITH MVFR VISBYS IN THE NORTHERN SAN JOAQUIN VALLEY EARLY TOMORROW
MORNING...ALTHOUGH THE PROBABILITY OF FOG FORMING IS A BIT LOWER
THAN YESTERDAY AS CONDITIONS ARE DRIER. LIGHT WINDS <10KTS ARE
EXPECTED THROUGH THE PERIOD. -DVC

&&

.STO WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$



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