Fog is causing flight delays at Philadelphia International Airport this morning.
The airport said delays are averaging 75 minutes.
The flight-tracking website FlightAware shows that dozens of flights to and from the airport have been delayed or canceled.
Earlier this morning, the Federal Aviation Administration issued a ground stop due to the weather conditions. That stop has been lifted, but delays are persisting, according to the airport.
Travelers should contact their airline, call 1-800-PHL-GATE or check phl.org for more information, the airport said.
The National Weather Service says the fog will likely cause low visibility this morning, with rain showers expected later in the day.