An excellent explanation of why this has occurred was explained in the BirdCast site.
Here in Massachusetts, the first sightings were on Nantucket Island, and I was contemplating traveling out to see the Northern Lapwing.
However, a report showed up on Massbird that told me that there was a Lapwing near to my house, so I could just drive to the location.
I immediately got my equipment together and left then drove to the Cumberland fields (an important birding area) and joined the observers that were already there. First thing that I did was to look through one of the observers spotting scopes and identify the lapwing, that way I could enter it on my life list. Then out came the camera lens and tripod to capture this “lovely” bird for posterity