I saw a Common Nighthawk over southwest Columbia (Boone Co.) this afternoon about 4 p.m. I wasn't going to post--thinking it a total fluke, but Kansas listserv has sightings for today, too.
Robbins & Easterla note: It is regularly seen, in much smaller numbers (usually only solitary birds are seen after the first week in Oct) through mid-Oct but rarely into the third week of Oct.
Late dates include 1 on 11 Nov 1989, Columbia (G. Perrigo)