The wind chill will feel like 15 to 20 below zero, according to the National Weather Service.
Schools are getting a head start on the weather this week. The expected frigid temperatures and black ice are prompting early calls for closures and delays.
A wind chill advisory will be in effect in the area from midnight tonight to 6 a.m. Wednesday, according to the National Weather Service. Temperatures will feel like 15 to 20 degrees below zero. A hazardous weather outlook is in effect through Sunday.
The extremely cold weather is also expected to push electricity demand to a new winter record, said the region's power grid operator, PJM Interconnection.
We'll continue to update this post tonight, so refresh and come back often.
CLOSURES
Bethlehem Area School District will be closed.
Clinton Township schools morning pre-kindergarten and kindergarten are canceled.
Easton Area School District has canceled all classes.
Nazareth Area school district will be closed.
Salisbury Township schools are closed, but the office will operate on a one-hour delay.
Saucon Valley school district is closed.
Parkland School District is closed. Offices will be open.
East Penn School District will be closed, and offices will also be closed.
Southern Lehigh School District is closed. Officers will be open with regular schedule.
DELAYS
Alpha Public School: 90-minute delay. School will begin at 9:30 a.m., and students may enter the building upon their arrival.
Bethlehem Township (N.J.) School District: two-hour delay.
Clinton Township schools will open two hours late due to the temperatures and possible black ice. Morning pre-kindergarten and kindergarten are canceled.
Greenwich Township School District: 90-minute delay
Hackettstown public schools are on a 90-minute delay.
North Hunterdon and Voorhees high schools: two-hour delay
North Warren Regional School District: two-hour delay.
Phillipsburg schools are reporting a 90-minute delay on Twitter.
For another list of updating delays and cancellations, click here.