About 3-ish last night I got up and looked out the window seeing mist.
It seemed quite thick but when I went for a walk at 6 am-ish there was
no trace of it.

Wouldn't the pavement slabs have been damp? Only one or two cars
(parked overnight on the road) showed a little dew.

OK, so it was an adiabatic thing but once there is precipitation or
condensation, it's out of the cycle, no?