We’ve never actually tried using a television as a tornado warning device, so we can’t completely vouch for it.
And of course, it’s best to make sure you’re in a safe place before trying it, we’d hate for you to be standing in front of your home entertainment center upstairs instead of huddled in your basement during a tornado warning.
Having said that, here are the instructions as we understand them.
First tune your television to Channel 13 (over the air, not cable) and darken the screen to almost black using your television’s brightness control.
You’re using Channel 13 as a control screen, because it’s said to be the VHF channel least affected by storms.
Next, turn to Channel 2. On the other end of the VHF spectrum, it supposedly is the most susceptible to storm interference.
Lightning will produce momentary colored bands of varying widths across your darkened screen. Ignore them. Watch instead for the screen to suddenly go totally bright.
According to those who claim this system works, this massive interference on your screen means that there’s a tornado within fifteen to twenty miles.
