2017 August 16
Seasonal Variations of Multiple Muons at the MINOS Near Detector (ND) and Far Detector (FD) are reported. The features of the data differ from the single-muon seasonal variations seen by both detectors and many other underground experiments. A satisfactory explanation for this result has not been put forward. A preliminary analysis of multiple-muon seasonal variation in the NOvA ND, located near the position of the MINOS ND, supports the MINOS observations.