Power was restored to all San Diego Gas & Electric customers Wednesday after thousands were left without electricity since the beginning of the week.

SDG&E issued warnings to more than 100,000 customers in high-impact areas across San Diego County that their power could be shut off to help prevent wildfires.

While longtime San Diego residents are likely familiar with the term, some may be new to the advisory. So, what exactly does a Red Flag Warning mean and why is it important?