A Red Flag Warning has been extended for portions of San Diego County ahead of another bout of strong Santa Ana winds.

The National Weather Service has issued a Red Flag waning for a wide swath of Southern California as Santa Ana winds are expected to bring dangerous fire weather to the region later this week.

The alert status for heightened combustion hazards in the county's inland valleys and mountains went into effect at 4 a.m. Wednesday and will last until 6 p.m. Friday.

Another round of Santa Ana winds has moved into Southern California and will spread south through San Diego County late Thursday. The additional dry air also is expected to worsen the region’s already very low humidity levels,

Another round of Santa Ana winds is forecast to sweep into SoCal on Thursday night into Friday morning, putting most of the region under a critical fire risk, as emergency responders battle to contain quickly spreading wildfires.