The Pennsylvania Department of Transportation and the Pennsylvania Turnpike Commission are "strongly urging motorists to avoid all unnecessary travel in eastern Pennsylvania, including the area from Harrisburg north to the New York border, east to the New Jersey border and south to the Maryland border" in an alert issued at midday.

The National Weather Service says there's still a chance of heavy rain in Lehigh and Northampton counties this afternoon.

As of 12:15 p.m. Thursday, Interstate 80 was closed in both directions from Exits 232 to 236 and Interstate 81 was closed in both directions between Exits 90 and 100. Also, hundreds of secondary roads are closed. 

The Delaware River continues to rise in Easton and is expected to crest around 8 a.m. Friday at a level that will put it among the city's top 10 worst floods. That forecast may change depending on additional rainfall. Flood waters reached Larry Holmes Drive this morning.

The Susquehanna River is causing extreme flooding in northeast Pennsylvania towns and mandatory evacuations are under way in cities such as Wilkes-Barre.

PennDOT says, "Many roads that are open are experiencing extremely high traffic, resulting in gridlock in many regions. In addition to flooding, mudslides and downed trees continue to pose safety risks along roadways in the rain-drenched regions."

Motorists can check road conditions on state roads by calling 511 or visiting www.511PA.com. 511PA, free and available 24 hours a day, provides traffic delay warnings, weather forecasts, average traffic speeds on urban interstates and access to more than 500 traffic cameras.

Follow PennDOT on Twitter at www.twitter.com/PennDOTNews.