Forecasters have highlighted Southern California, including downtown Los Angeles, for a rare “high risk” of flash flooding on Sunday and Monday due to a potent atmospheric river.
Forecasters have highlighted Southern California, including downtown Los Angeles, for a rare “high risk” of flash flooding on Sunday and Monday due to a potent atmospheric river that promises to dump several inches of rain across the region.
California Gov. Gavin Newsom even declared a State of Emergency for several counties in Southern California to support storm response and recovery efforts.
The “high risk” is the highest rung on NOAA’s flash flood threat scale and is only issued under the most dire of flooding forecasts.
The storm has already lashed northern and central sections of the state, and snow is already accumulating along the Sierra Nevada.
“The high risk was also expanded south to cover all of Los Angeles County to the south of the Transverse Range as per coordination with (the National Weather Service office in Los Angeles),” NOAA’s Weather Prediction Center (WPC) said. “Life-threatening flash and urban flash flooding possible in the high risk area.”
The WPC warned that this is a Category 5 atmospheric river, the top category.
The Golden State mobilized and prepositioned a record 8,500 emergency responders ready for flooding, landslide and travel emergencies, according to the Governor’s office.
The State of Emergency included Los Angeles, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo and Ventura Counties.
The National Weather Service office in Los Angeles continues to use strong language in its forecasts, indicating a significant threat of widespread and dangerous flash flooding through Monday.
Forecasters warned that flooding issues would not be confined to the usually prone areas in the foothills, mountains and burn areas and that numerous mudslides and debris flows are expected.
Additionally, moist, unstable air will likely trigger scattered strong to even a few severe thunderstorms along and just off the Central California coast.
Some storms could spawn waterspouts Sunday across the central and southern coastal waters from the Santa Barbara channel north past Santa Cruz.
