Traffic in and around I-93, I-393, and State Route 106 will be significantly altered this weekend due to the NASCAR race at New Hampshire Motor Speedway in Loudon. The race is scheduled for Sunday, Sept. 21, at 2 p.m., with an expected turnout of approximately 15,000 vehicles. As in past years for the race, New Hampshire State Police and the Department of Transportation are making several temporary lane changes for these state routes and interstates. The I-93 Exit 14 southbound off-ramp to Loudon Road and the I-93 Exit 15E southbound off-ramp to I-393 eastbound will be closed. At the I-393 and I-93 interchange, the I-93 northbound off-ramp to I-393 west (Exit 15W) will be closed.