Weather Forecast for the Week of January 17 to 23...
... A MAJOR PATTERN CHANGE IS EXPECTED NEXT WEEK WITH THE POTENTIAL FOR EXCESSIVE RAINFALL AND STRONG WINDS...
A MAJOR CHANGE IN THE UPPER LEVEL PATTERN IS EXPECTED TO BEGIN ON SUNDAY AND CONTINUE THROUGH NEXT WEEK. A VERY POWERFUL WEST TO EAST JET STREAM SAGGING SOUTHWARD THROUGH THE PACIFIC WILL BREAK DOWN THE PERSISTENT RIDGE ACROSS THE WEST COAST. THIS WILL ALLOW STORM SYSTEMS TO TRACK INTO SOUTHERN CALIFORNIA WHILE MAINTAINING A RICH SOURCE OF SUBTROPICAL MOISTURE.
CONFIDENCE IS GROWING THAT SIGNIFICANT AND POSSIBLY EXCESSIVE RAINFALL WILL OCCUR OVER SOUTHWESTERN CALIFORNIA FROM SUNDAY THROUGH MOST OF NEXT WEEK... BUT THE EXACT DETAILS OF TIMING ARE STILL UNCLEAR. AT THIS TIME... IT APPEARS THERE WILL BE THREE OR FOUR SEPARATE STORM SYSTEMS MOVING INTO THE AREA BETWEEN LATE SUNDAY AND FRIDAY. FOR THE ENTIRE WEEK... THERE IS THE POTENTIAL FOR RAINFALL TOTALS OF 4 TO 8 INCHES IN COASTAL AND VALLEY AREAS... AND 8 TO 16 INCHES IN THE FOOTHILLS AND MOUNTAINS. LOCAL RAINFALL AMOUNTS OVER 20 INCHES WILL BE QUITE POSSIBLE ACROSS FAVORED SOUTH FACING COASTAL SLOPES.
THE STRONG SOUTHERLY WINDS THAT ARE PROJECTED AT TIMES NEXT WEEK COULD BRING SIGNIFICANT OROGRAPHIC ENHANCEMENT OF RAINFALL ACROSS SOUTH FACING SLOPES. RAINFALL RATES OF AROUND ONE INCH PER HOUR WILL BE POSSIBLE DURING THE PEAK TIMES OF HEAVIEST RAINFALL... WHICH CURRENTLY APPEAR TO BE MONDAY... AS WELL AS LATE WEDNESDAY INTO THURSDAY. EARLY INDICATIONS ALSO SHOW THE POSSIBILITY OF EMBEDDED THUNDERSTORMS AT TIMES DURING THE WEEK... WHICH COULD BRING LOCALIZED RAINFALL RATES IN EXCESS OF ONE INCH PER HOUR.
http://www.weather.com/weather/alerts/l ... 4071b4f4fc

