Blizzards can be very dangerous especially if you're out walking in the Blizzard or driving in the Blizzard.
A Blizzard can pile snow up and can cause blinding conditions while driving and the snow could pile up and leave you stranded out in the cold or even cover you completely with snow.
Blizzards can also cause power outages due to the strong winds and weight of the snow.
During a Blizzard or when a Blizzard is forecast don't venture out into the Blizzard unless you have no other choice.
Stay put inside your house or building where it's warm until the Blizzard has gone away and before the blizzard has a chance to get to your place stock up on food and other needed items and make sure you have some other form of heat source should the power go out and your furnace not work.