Blizzards affect people by shutting down cities and transportation systems, damaging property, hurting the economy and causing injuries and loss of life. Blizzards affect the environment by damaging or destroying trees, plants and crops and causing flooding when large amounts of snow melt.
The amount of snow deposited by a blizzard can make it difficult or even impossible for people to move freely. Roads blocked with snow can make transportation impractical, and the loss of power can make it difficult for businesses and other organizations to function. When workers cannot get to work and businesses cannot run, the local economy is damaged.
Blizzards can also cause massive property damage due to roof collapses, windows breaking and damage to cars and houses from falling trees. The inclement conditions caused by blizzards are also hazardous to humans, and the cold temperatures can even prove fatal.
In terms of environmental damage, blizzards can wreak havoc on plants and trees, damaging natural features and killing crops due to extreme cold. Even after a blizzard ends, flooding can occur due to excess snowfall. If temperatures increase significantly after a blizzard, snow turns to water faster than the land can absorb it, causing flooding.