PROJECT ALERT NOTICE (CA) CA: AR brings heavy and intense precip, causing SoCal flooding

Date: Thu, 06 Dec 2018 19:59:09 EST

Summary: A stronger-than-predicted atmospheric river brought heavy and intense precipitation to parts of southern California today, causing local flooding and triggering mud slides and debris flows.

Los Angeles and surrounding areas in southern California are experiencing flooding, mudslides, and debris flows following heavy and intense rainfall from a stronger-than-predicted AR Storm. This storm was predicted to be a long duration widespread event with rates not expected to create issues for recent burn areas like the Woolsey, Hill, and Thomas Fires in Ventura County; however, the storm intensified bringing 2-4 inches of rain to Los Angeles and surrounding areas of southern California during the past 24 hours. Currently, streamflows are elevated, but only one flood forecast point is expected to rise above flood monitor stage.

Late today, the California Water Science Center deployed 2 crews for flood response from the Redlands, CA (1) and Santa Maria, CA (1) service areas. Additional crews are expected to deploy tomorrow for high flow and recessional measurements. Currently, all streamgages are transmitting data. No gage damage or safety issues have been reported, but an M9 was damaged beyond repair during an attempted high flow measurement at a debris-laden urban flood channel in Los Angeles.