A Malibu wildfire that has forced people to evacuate and destroyed homes broke out amid a rare weather advisory warning of particularly dangerous conditions, which will remain in place through the afternoon Tuesday.

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?

Red flag warnings are in effect across eight states, including nearly 43 million people in the northeast as fire danger remains elevated.