The Federal Aviation Administration issued a ground stop Wednesday at the San Diego International Airport as a gray haze of fog closed in on downtown San Diego and its surrounding areas .

The ground stop was issued at about 7:15 a.m. and lasted until 8:30 a.m. due to low ceilings at the airport, the FAA said.

The aviation agency estimated anywhere from 30-60 flights could be affected by the ground stop. According to the flight tracking website FlightAware, 32 flights were delayed as of 8:30 a.m. with no cancelations when the stop was lifted.

A dense fog advisory issued by the National Weather Service was set through 9 a.m. Low visibility was possible up and down the San Diego County coastline with visibility in some areas less than a quarter-mile, the NWS said.

The same weather pattern was expected to continue through Friday.

This is a developing story. Details may change as information is released.