Winter truck load increases will begin Friday on unrestricted highways in the central frost zone, according to the Minnesota Department of Transportation.

The frost zones can be found on the MnDOT load limits map. Winter load increases have already begun in the north and north-central zones.

Vehicles will be allowed to operate up to 10 percent over the standard legal maximum loads on unrestricted highways during the winter load increase period. However, trucks must comply with current registration weight laws and not exceed registered gross weight tolerances.

Drivers should check with local agencies before increasing any weights on city, county and township routes. The sign erected on the roadway governs the load limit in effect. A winter weight increase permit is required to take advantage of the 10 percent weight increase on interstate highways only; a permit is not required for state trunk highways.

For questions about over legal weight/size “heavy haul” trucking, call MnDOT’s Freight and Commercial Vehicle Operations – Oversize/Weight Permits at 651-296-6000 or email ofcvopermits.dot@state.mn.us.

For questions about enforcement, call the Minnesota Department of Public Safety, State Patrol Commercial Vehicle Enforcement at 651-405-6196.

The start and end dates for winter load increases are based on how weather is affecting roadway strength.

These dates are established by monitoring roadway strength as weather conditions change. The end date for winter load increases is variable and drivers should check for updates throughout the year. Vehicle operators are required to check with MnDOT for the exact start and end dates.

All changes are made with a minimum three-day notice.

For the most current information, go to MnDOT’s automated 24-hour message center at 800-723-6543 for the U.S. and Canada, or 651-366-5400 for the Minneapolis/St. Paul area. This information is also published on the MnDOT seasonal load limits website at www.dot.state.mn.us/materials/.

For updated road condition information, call 511 or visit www.511mn.org.