What to KnowA Red Flag Warning is issued for San Diego's mountains and valleys from 4 a.m. Wednesday to 6 p.m. Thursday due to elevated fire weather conditions. A high wind warning is in effect for the coast starting at 4 p.

The National Weather Service has issued a Red Flag Warning for San Diego County due to high winds and low humidity.

San Diego County — in the midst of one of the driest periods on record — will be lashed by unusually cold and expansive Santa Ana winds early Wednesday that could spark wildfires, snap trees and knock out power,

Cal Fire says it’s preparing for critical fire risk across San Diego County by shifting resources from northern areas and canceling days off as Southern California faces dangerous Santa Ana winds and a red flag warning.

Santa Ana winds will create extreme fire danger and bring the possibility of damaging winds not seen in 10-plus years for some areas.

In the face of what's predicted to be an intense Santa Ana windstorm, additional firefighting resources will be deployed throughout San Diego County for the remainder of the week, it was announced Monday.