Chilly, Yes; Not so Much Rain or Wind?

OK, the Bay Area NWS has moved the pattern-change thinking ahead quite a bit tonight, at least according to this amateur's interpretation of the fresh forecast disucssion. It's not going to be very wet in the Sacramento-Folsom corridor Sunday morning, if at all, but it will be chilly. The middle of next week California will be slammed with heavy rain and strong winds.

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA CA
910 PM PST TUE DEC 1 2009

...NO SIGNIFICANT WEATHER EXPECTED THROUGH SATURDAY. A MAJOR PATTERN CHANGE BY EARLY NEXT WEEK WILL PRODUCE A PERIOD OF STORMY WEATHER WITH A CHANCE FOR HEAVY RAINFALL.

... ECMWF AND GFS ARE NOW COMING INTO BETTER AGREEMENT ON HOW THE PATTERN WILL INITIALLY EVOLVE FROM DRY TO WET. BOTH MODELS INDICATE THAT A PIECE OF ENERGY FROM THE SYSTEM CURRENTLY BETWEEN 140 AND 150W WILL BREAK OFF AND MOVE OVER THE TOP OF THE RIDGE DURING THE NEXT 48 HOURS...INGEST SOME COLD CANADIAN AIR...AND FORM A CLOSED UPPER LOW OVER OR NEAR THE PAC NW BY FRIDAY AFTERNOON. MEANWHILE A WETTER AND MORE POWERFUL SYSTEM IS POISED TO BREAK UNDER THE RIDGE AND APPROACH CA FROM THE DUE WEST BY LATE IN THE WEEKEND. MOST RECENT MODEL OUTPUT INDICATE THAT THE COLD SYSTEM OVER THE PAC NW WILL SAG FAR ENOUGH SOUTH TO DEFLECT MOST OF THE MOISTURE FEEDING IN FROM THE WEST...AND THAT SOUTHERN CALIFORNIA WILL GET THE BRUNT OF THE PRECIP FROM THE FIRST SYSTEM EARLY NEXT WEEK. WE`LL LIKELY SEE SCATTERED SHOWERS SOMETIME LATE IN THE WEEKEND AND INTO MONDAY. FOR OUR AREA... THE HIGHEST RAINFALL TOTALS WITH THIS FIRST SYSTEM WILL LIKELY BE ACROSS OUR SOUTHERN-MOST COUNTIES...THE AREA CLOSEST TO THE BEST MOISTURE INFLUX. BUT RAINFALL AMOUNTS DO NOT LOOK OVERLY IMPRESSIVE ANYWHERE IN OUR AREA THROUGH MONDAY. MUCH MORE SIGNIFICANT RAINFALL IS LIKELY TO FOLLOW FROM THE MIDDLE OF NEXT WEEK ONWARD AS A STRONG AND WET FLOW ACROSS THE PACIFIC BREAKS FULLY THROUGH AND DELIVERS PERIODIC RAIN EVENTS (LIKELY HEAVY) FROM TUESDAY NIGHT OR WEDNESDAY ONWARD. PERIODS OF STRONG WIND AND HEAVY SEAS WILL OCCUR AS WELL BEGINNING AROUND THE MIDDLE OF NEXT WEEK. THE HAZARDOUS WEATHER STATEMENT WILL BE UPDATED SHORTLY TO MORE ACCURATELY REFLECT THE MOST RECENT FORECAST GUIDANCE.