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000
FXUS66 KSTO 150444
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
940 PM PDT FRI JUN 14 2013

.SHORT TERM DISCUSSION...

INCREASING SWLY/ONSHORE FLOW WILL PROVIDE AN AMELIORATING INFLUENCE
ON TEMPS/HUMIDITY LEVELS THIS WEEKEND. MAYBE A CHANGE UP TO 2 DEG
COOLER ON SAT AND POSSIBLY AGAIN ON SUN OVER MANY LOCALES. WEAK
SHORT WAVE MOVING THROUGH SWLY FLOW ASSOCIATED WITH PATCHES OF
CIRRUS NOTHUS CLOUDS. WITH THIS FEATURE MOVING THROUGH THE AREA...A
CLEARER SKY EXPECTED ON SAT. VERY WEAK RIPPLE EMBEDDED IN SWLY FLOW
PASSING NORTH OF OUR CWA MAY TRIGGER SOME BUILDUPS OVER TRINITY ALPS
IN THE AFTERNOON.

.PREVIOUS DISCUSSION...

LOOKING UPSTREAM...UPPER LOW CURRENTLY INVOF 48N 138W IS
DIGGING AND DEEPENING IN RESPONSE TO NEAR 100 KT JET STREAK DROPPING
INTO WEST SIDE OF LOW. SYSTEM PROGGED TO REMAIN QUASISTATIONARY OVER
THE WEEKEND WITH DRY SOUTHWEST FLOW ALOFT OVER NORCAL. DELTA BREEZE
FORECAST TO STRENGTHEN SATURDAY AND CONTINUE MODERATE INTO SUNDAY.
SLIGHT COOLING EXPECTED OVER THE WEEKEND WITH NEAR TO SLIGHTLY ABOVE
NORMAL TEMPS.

MODELS SLOWLY PROGRESS LARGE OFFSHORE UPPER LOW TOWARDS THE WEST
COAST EARLY NEXT WEEK SHIFTING IT INLAND ACROSS THE PACNW WED INTO
THU. THIS WILL BRING INCREASING ONSHORE FLOW THROUGH MIDWEEK WITH
SYNOPTIC COOLING FOR INTERIOR NORCAL. MAIN DYNAMICS AND MOISTURE
REMAIN NORTH OF THE CWA BUT MAY BE ENOUGH INSTABILITY TO BRING A FEW
SHOWERS TO THE MOUNTAINS OF SHASTA COUNTY TUE/WED. LOW 80S PROGGED
IN THE CENTRAL VALLEY BY TUE/WED WITH 60S TO 70S FOR THE MOUNTAINS
AND FOOTHILLS.

PCH

.EXTENDED DISCUSSION (TUESDAY THROUGH FRIDAY)

THE UPPER LOW GRADUALLY SHIFTS INLAND THROUGH NEXT WEEK. THE MAIN
EFFECT WILL BE TO COOL TEMPERATURES TO BELOW NORMAL LEVELS AT
LEAST THROUGH MID WEEK. THERE IS ALSO A SLIGHT CHANCE OF RAIN
SHOWERS OVER THE MOUNTAINS OF SHASTA COUNTY. SOME WARMING IS
POSSIBLE BY THE END OF THE WEEK DEPENDING ON THE DEPARTURE SPEED
OF THE LOW. HIGHS COULD REACH SLIGHTLY ABOVE NORMAL LEVELS BY
FRIDAY. EK/DANG

&&

.AVIATION...

MAINLY VFR CONDITIONS THE NEXT 24 HOURS. IFR CIGS DUE TO STRATUS MAY
MOVE INLAND TO AROUND VALLEJO LATE TONIGHT. INCREASING ONSHORE FLOW
EXPECTED TO INCREASE SWLY AND UP VALLEY FLOW OVER TAF SITES THIS
WEEKEND.

&&

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

$$