Hundreds of people are missing in California's Camp Fire. With each day that goes by, their families refuse to let hope wane.

Due to the wildfires raging in Northern California, San Francisco, Stockton and Sacramento were the world's three "most polluted cities" on Friday morning, according to Berkeley Earth, a nonprofit that aggregates data from air-quality monitoring sites.

Nick Meas lost the Paradise home where he grew up in the Camp Fire that's ravaging Northern California.

Evacuees who fled the Camp Fire in California are facing norovirus outbreaks in shelters. The Butte County Public Health Department said that 145 people have been sick with vomiting and/or diarrhea since the shelters opened to evacuees and 41 people were experiencing symptoms at four different shelters as of Wednesday evening.

Brynn Parrott Chatfield saw the smoke rising above the pine trees near her home in Paradise, California. When she heard the trees blow up and saw the huge pieces of ash, she knew it was time to get out.