NATIONAL WEATHER SERVICE SACRAMENTO CA 940 AM PST THU FEB 10 2011
REGARDING THE PATTERN CHANGE NEXT WEEK...THE 12Z GFS CAME IN WITH LOWER 1000-500MB THICKNESSES MONDAY NIGHT...547 DM...MEANING SNOW LEVELS COULD START OUT NEAR 5500 FEET. THE ECMWF IS A BIT SLOWER WITH THE ONSET OF PRECIPITATION...BUT HAS THE SAME GENERAL SCENARIO DEVELOPING NEXT WEEK. THE CURRENT STORM NEAR THE GULF OF ALASKA FLATTENS THE UPPER RIDGE THIS WEEKEND AS THE FLOW ALOFT TURNS SOUTHWESTERLY. WE SEE A BIG RIDGE BUILD OUT NEAR THE DATELINE CARVE OUT A DEEP TROF DOWNSTREAM ALONG 140W. A COLD FRONT WILL MOVE INTO THE REGION AFTER MIDNIGHT MONDAY NIGHT...POSSIBLY BRINGING STRONG WINDS WITH VALLEY RAIN AND MOUNTAIN SNOW TO THE REGION. THE LONG WAVE TROF MAY SLOWLY SHIFT INLAND THROUGH MID-WEEK AS RE-ENFORCING SHOTS OF ENERGY ROTATE THROUGH IT. THE GFS HAS A 982MB SURFACE LOW OFF THE OREGON COAST EARLY TUESDAY...SO IT COULD BE WINDY IN THE VALLEYS AS WELL. ADDITIONALLY THE GFS AND ESRL EXPERIMENTAL RE-ANALYSIS PRODUCTS INDICATE A BOMB OF A SURFACE LOW COMING OFF EAST ASIA AROUND VALENTINES DAY. THIS ENERGY COULD BECOME ENTRAINED INTO THE JETSTREAM AND CAUSE AN ADDITIONAL ROUND OF COLD AND WET WEATHER TOWARD THE END OF THE WEEK. WATCH FOR A SPECIAL WEATHER STATEMENT REGARDING THE PATTERN CHANGE THIS AFTERNOON. SG
