Sandstorms occur in very dry regions that have poor vegetation, such as deserts, northern China, and the Great Plains in the US.
The intensity of the winds varies by region, ranging from what we call dust lifting to sandstorms themselves, with winds that can exceed 100 km / h.
Thunderstorms or dust lifting interfere with greater or lesser visibility.
When visibility is reduced to 1.5 km to 10 km, dust is said to form. When it is reduced to less than 1.5 km, dense dust or storm formation is said to occur.
Sandstorm in Phoenix City, Western United States, Year 2011