I live on approach to 15R at BOS. Early this morning I heard a craft flying very low and making an unusual noise. I opened a flight tracking app and saw Southwest WN1941 from STL miss its landing. It then flew down to Plymouth and turned. I thought it was going to make another approach to Logan from the south but instead it turned SW and climbed. It was diverted to BWI.
At around this time, other craft landed on 15R.