Christmas travel could be affected by flood threats in California and heavy snow in New England

Residents of Los Angeles spent the day before Christmas under rain showers and winds of around 40 mph, while the New England area braces for heavy snow later in the week.

Residents of Los Angeles spent the day before Christmas under rain showers and winds of around 40 mph, while the New England area braces for heavy snow later in the week.

More than 40 million people were under flood alerts Wednesday morning, including most of California, as well as parts of southern Nevada and western Arizona. The heavy rain triggered numerous flash flood warnings in and around Los Angeles County.

California Gov. Gavin Newsom declared a state of emergency for Los Angeles, Orange, Riverside, San Bernardino, San Diego and Shasta counties.

He said the order will "activate emergency authorities and preposition resources to keep our communities safe."

"We're expecting continued impacts into the weekend," Courtney Carpenter, a meteorologist with the National Weather Service office in Sacramento, said in a video shared by the state's emergency agency.