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000
FXUS66 KSTO 142200
AFDSTO

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

.SHORT TERM DISCUSSION...

WEAK UPPER TROUGHING CONTINUES OVER NORCAL TODAY WITH SOME
ASSOCIATED HIGH CLOUDINESS. SURFACE HIGH PRESSURE EXTENDS FROM THE
EPAC THROUGH OREGON INTO THE GREAT BASIN. RELATIVELY TIGHT N-S LOW
LEVEL PRESSURE GRADIENT THIS MORNING HAS WEAKENED THIS AFTERNOON
ALLOWING CANCELLATION OF THE RED FLAG WARNING. AFTERNOON TEMPS
RUNNING UPWARDS OF 7 DEGREES WARMER THAN 24 HOURS AGO AND HIGHS
WILL TOP OUT IN THE UPPER 80S TO LOWER 90S IN THE CENTRAL VALLEY.

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 STRATUS MAY MOVE
INLAND TO AROUND VALLEJO LATE TONIGHT. NORTHWEST WINDS AROUND 10
KT ACROSS THE VALLEY THIS AFTERNOON WILL BECOME GENERALLY LIGHT
TONIGHT. NEAR THE DELTA...SOUTHWEST WINDS AROUND 10 KT WILL
INCREASE TO 20-25 KT THIS EVENING AND TONIGHT.

DANG


&&

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

$$