PHILADELPHIA (AP) — PHILADELPHIA (AP) — The National Weather Service has posted a dense fog advisory for parts of eastern and east-central Pennsylvania overnight.

Forecasters say the advisory would remain in effect from 7 p.m. Sunday until 7 a.m. Monday. They say the fog will reduce visibility to less than a quarter-mile at times, resulting in hazardous driving conditions.

The fog has been causing some flight delays at Philadelphia International Airport, where spokeswoman Victoria Lupica says some arriving flights Sunday have been delayed for as much as 2½ hours.

The airport is advising travelers to check on their flight status by calling airlines, looking on www.phl.org or calling the toll-free flight information number: 1-800-745-4283.

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