A wind-driven wildfire charred dozens of acres in the sparsely developed northeastern reaches of San Diego County, damaging structures and forcing pre-dawn evacuations before crews could gain the upper hand on the flames Wednesday.

Millions of California residents were placed under a red flag warning through Thursday amid threats of further fires with looming winds in the forecast, according to multiple reports.

A rare Particularly Dangerous Situation warning has been issued for Southern California as a powerful and potentially damaging Santa Ana wind event​ is expected.