A few things I gathered from an archived ATC recording:
AC624 requested maximum aerodrome light intensity early in the approach, it was 4/5 at the time, supposedly going up to 5/5 later but it's hard to tell from the recording.
When the tower controller cleared AC624 to land, he reported winds 010 20G30. Nothing out of the ordinary for CYHZ. The visibility was probably the dominant weather factor, 1/2sm or less due to the blowing snow.
My ATC recording stops presumably when the aircraft contacted the power lines, knocking out the local scanner.
The aircraft certainly did not touchdown before the power lines, it would have nosed into the embankment leading up to the antenna array. Otherwise the story would have been much worse.
CYHZ has a reputation for frequent IFR conditions. Maybe it's a good time to install a proper ILS system on both ends of its longest runway.
I'll have popcorn ready for the explanation of going below the MDA.