Severe Thunderstorm Warning 12, NWS Sacramento, CA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
925 AM PDT SAT MAY 3 2003

INTERESTING SIGHT LOOKING EAST OUTSIDE OUR WINDOW AS MODERATE CU ARE
FORMING RAPIDLY UNDER AN AC DECK.  LATEST LAPS DATA SHOWED
ESTIMATED SURFACE CAPES HAVE JUMPED TO 660 J/KG OVER EASTERN SAC
COUNTY.  VISIBLE SATELLITE SHOWING SOME TCU BREAKING THROUGH THE AC
LAYER OVER THE MOTHERLODE.  UPPER LOW...WITH ASSOCIATED SHORTWAVE
ROUNDING THE BOTTOM OF LOW...CONTINUES TO DRIFT EASTWARD JUST OFF
THE CENTRAL CA COAST.  WITH SOME BREAKS IN THE OVERCAST THIS
MORNING...COULD SEE SOME DEVELOPMENT OF HEAVIER SHOWERS OR
THUNDERSTORMS OVER AREA.  THIS IS ESPECIALLY TRUE OVER THE EASTERN
SIDE OF THE VALLEY AND ADJACENT FOOTHILL REGION WHERE SKIES HAVE
GONE BROKEN...AND ALONG THE DEFORMATION ZONE OVER THE INTERIOR
COASTAL RANGE AND NORTHERN SAC VLY.

PRECIPITATION OVER THE NORTHERN SIERRA SHOULD INCREASE LATER TODAY
AS UPPER LOW IS PROGGED TO OPEN UP.  THIS WILL RESULT IN BETTER
OROGRAPHICS OVER THE WEST SLOPES OF THE NORTHERN SIERRA. TROF WILL
RAPIDLY MOVE EASTWARD AS NEXT STRONG SHORTWAVE IS CURRENT DIVING
RAPIDLY OFF THE BC COAST.  THIS SYSTEM WILL BRING ANOTHER ROUND OF
RAIN IN THE VALLEY THIS EVENING AND MORE MOUNTAIN SNOW THROUGH THE
NIGHT.  12Z ETA MODEL CONTINUES THE TREND OF MOVING THE TROF THROUGH
NORTHERN CA EARLY SUNDAY. THUS...PRECIPITATION CHANCES WILL DECREASE
BY NOON SUNDAY OVER THE VALLEY AND NORTHERN INNER COASTAL
RANGE...BUT MAY CONTINUE THROUGH THE AFTERNOON HOURS OVER THE
NORTHERN SIERRA. A BREAK IN THE UNSETTLED WEATHER STILL LOOKS GOOD
FOR MONDAY AND TUESDAY.  LAM

.STO...SNOW ADVISORY SATURDAY AND SATURDAY NIGHT FOR
       WESTERN PLUMAS COUNTY INCLUDING LASSEN PARK...AND THE
       WEST SLOPES OF THE NORTHERN SIERRA NEVADA.

CAZ013>019-063-064-066>069-041400-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SACRAMENTO CA
700 AM PDT SAT MAY 3 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR INTERIOR NORTHERN CALIFORNIA.

.DAY ONE...TODAY

UPPER LEVEL LOW PRESSURE SYSTEM CENTERED NEAR THE CENTRAL CALIFORNIA
COAST WILL CONTINUE TO BRING RAIN SHOWERS TO THE INTERIOR OF NORTHERN
CALIFORNIA AND SNOW TO THE HIGH COUNTRY. ISOLATED THUNDERSTORMS ARE
ALSO POSSIBLE TODAY AND THIS EVENING. ANOTHER DISTURBANCE FROM THE GULF OF
ALASKA WILL HELP TO BRING ADDITIONAL HEAVY SNOW AND LOWER SNOW
LEVELS TONIGHT ACROSS THE SIERRA NEVADA. A SNOW ADVISORY IS IN
EFFECT FOR THE WEST SLOPES OF THE NORTHERN SIERRA NEVADA...WESTERN
PLUMAS COUNTY AND LASSEN VOLCANIC PARK FOR TODAY AND TONIGHT. (SEE
WWUS46 KSTO - WSWSTO FOR DETAILS).

.DAYS TWO THROUGH SEVEN...

NO HAZARDOUS WEATHER IS EXPECTED THROUGH THE REMAINDER OF THE
FORECAST PERIOD.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS TO THEIR LOCAL NATIONAL WEATHER SERVICE.

THE LATEST WEATHER INFORMATION IS AVAILABLE ON THE INTERNET
AT (LOWER CASE): HTTP://WWW.WRH.NOAA.GOV/SACRAMENTO

TARDY

CAZ017>019-040100-
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SACRAMENTO CALIFORNIA
250 PM PDT SAT MAY 3 2003

...FUNNEL CLOUDS POSSIBLE THIS AFTERNOON ACROSS PORTIONS OF THE
CENTRAL VALLEY...

A LOW PRESSURE SYSTEM MOVING ACROSS NORTHERN CALIFORNIA THIS
AFTERNOON IS CREATING AN UNSTABLE ATMOSPHERE THAT IS RESULTING IN
SCATTERED SHOWERS AND THUNDERSTORMS. SOME OF THESE STRONGER STORMS
MAY PRODUCE BRIEF HEAVY RAIN...SMALL HAIL...AND POSSIBLY EVEN A FEW
FUNNEL CLOUDS. AT 240 PM...THE PUBLIC REPORTED A FUNNEL CLOUD NEAR
BRENTWOOD IN EASTERN CONTRA COSTA COUNTY THAT WAS MOVING INTO
WESTERN SAN JOAQUIN COUNTY. KEEP AN EYE TO THE SKY THIS AFTERNOON...
AND IF THREATENING WEATHER APPROACHES MOVE INDOORS.

DFR