In my experience, you still can't tell what you are seeing in the lightening flash. Especially rain wrapped funnels. Just flash light and blackness.
In a strange twist of fate, I found myself evacuating to my basement shelter at 3:00 AM last night with the tornado siren blaring. I did look out. Couldn't see squat with trees, howling wind and sheets of rain. It was the leading wall edge w/ no lightening yet. No tornado touched down, but some of the Bradford Pears were snapped off and other limbs snapped.