What is a black blizzard?
During the drought in 1930s , the unanchored soil turned into dust, which was blew by prevailing winds away in huge clouds that sometimes/often blackened the sky.
These billows of dust were named black blizzards or black rollers.
They traveled across country, reaching as far as the East Coast and striking cities (New York City and Washington, D.C). On the Plains, they often reduced visibility to 1 metre (3.3 ft) or les
Here you can see a black blizzard from 1934 - South Dakota