ALLENTOWN, Pa. — Hundreds of members of the Pennsylvania National Guard are being called up to help deal with a winter storm that's expected to dump more heavy snow on parts of the state.

Guard spokesman Sgt. Matt Jones says the first 350 troops were activated about 8 a.m. today and assigned to storm duty in northeastern and southwestern Pennsylvania. Jones says they'll put in a 12-hour shift, then be relieved by 350 fresh troops.

Earlier today, PennDOT dispatched a special response team in Western Pennsylvania to help treat Interstates 84 and 380 in the Poconos. Six plows, a snowblower, and 14 workers were sent to supplement local PennDOT equipment.

The storm has prompted hundreds of schools to close across eastern Pennsylvania, where snowfall totals of more than a foot are possible.

Forecasters say that winds could reach 45 mph across a swath of the Northeast from central Pennsylvania to coastal Maine.

Combined with a wet, dense snow falling in Pennsylvania, New York and New Jersey, that could mean toppled trees and power lines.

Hundreds of commercial airline flights in the region have already been canceled.