The state just got back to me and the mystery is solved, an error is corrected, and it turns out there wasn't an entire tire to blame.

A state police spokesman tells me Dorothy Lovenbury, 51, of Dunbarton, NH, was driving the white Kia pictured below on Interstate 495 near exit 33 in Chelmsford when the tread from a dump truck tire came off the tire and struck her car windshield.

As you can see, it did a fair amount of damage.

Lovenbury was taken to Lowell General Hospital with minor injuries to her hands.