GUILFORD COUNTY, N.C. - After a winter snow storm, Guilford County Schools is preparing for students to return to class on Monday.

Even though the snowfall is over, the cold temperature is still a concern.

School buses have been parked in the cold since last week due to school closings.

School buses need extra time to get warm when the temperature drops.

Guilford County School's Transportation Director Jeff Harris says school buses take about 15 minutes to get warm.

Bus drivers could be late when it comes to picking up students in the morning if buses do not run properly due to cold temps.

School officials are asking parent to keep an eye on their kids and bring them inside to wait if it's too cold outside.

GCS says mechanics are working and checking buses to make sure everything runs smoothly.

When it comes to making a decision about closing or delaying school, GCS says once there's evidence of snow on the roads the transportation director and staff survey areas throughout the county to determine road conditions.