The National Weather Service in Mount Holly issued a winter-storm warning for heavy snow and ice in northeastern Pennsylvania and northwestern New Jersey into Monday night, following a winter-weather advisory for the Philadelphia region Sunday.

The Central Bucks School District announced that its schools would be closed Monday “due to inclement weather.”

With snow in some areas potentially falling at about an inch an hour, PennDot has begun deicing roads and activated its command centers. Beginning midnight, PennDot and the Pennsylvania Turnpike Commission are imposing the following restrictions to I-84, I-380, I-81 from the junction with I-80 to the New York border, I-476 north of the Lehigh Valley exit , I-78 and I-80 eastbound from I-81 to the New Jersey border, US-22 from I-78 to the New Jersey border, State Route 33:

  • The speed limit is lowered to 45 miles an hour.
  • Commercial vehicles must drive in the right lane. (New Jersey has a full commercial vehicle ban on I-78 and I-80.)
  • All double trailers are banned, regardless of whether they have chains.
  • Empty trailers are banned.
  • Passenger vehicles pulling trailers are banned.
  • RVs and motor homes are banned.
  • School buses and commercial buses are banned.
  • Motorcycles are banned.

Depending on the weather, the speed limit could be lowered even further, and the restrictions could be expanded to other areas.

The restrictions have no predetermined expiration time.

The latest information on restrictions and conditions for specific routes — including plow truck status — is available through the 511PA service at 511PA.com, the 511PA iPhone and Android apps, or by calling 511.

Inquirer staff writer Ellie Silverman contributed to this article.