UA 3236 then UA 654 at Houston
Midland → Houston → Washington National
Timetable, Houston time
18:30UA 3236 from Midland at the gate
12:07UA 654 to Washington National leaves the gate
17 h 37 apart on the timetable, overnight
UA 654 leaves 17 h 37 after UA 3236 arrives on the timetable: more than half a day, so not a connection we count.