In the forties there used to be a piece of kit in Air Traffic called a 'Porka'. This was a miniature motar and would fire a flare vertically when required.
Should the airfield be socked in with fog then an aircraft would get steers to the airfield at 1,000ft. Just before he reached the overhead they would fire the Porka so that the pilot would see where the tower was. He would pass it and carry out a timed circuit: Rate one turn/one minute/descending Rate one turn, that hopefully would have him on finals at 2/300 ft. in a position to see the runway.
They were out of date when I started but we were still taught timed circuits. Seemed to work OK.