The name Haboob is the rooted from the Arabic word "phenomena". This form of monsoon occurs from May until September. It's a dust storm moving at a maximum speed of 80kph (50mph), the average speed is 50kph (30mph). The storm can reach up to heights of 3000 feet. They last about three hours, in which they change the desert landscape.
The Haboob wind is caused by thunderclouds in a final phase. Downdrafts in a thunderstorm causes gust fronts, descending air hitting the grond and picking up large amounts of dust. The force moves the dust from above.

In the Sahara there are 2 types of the Haboob. In the south a strong and hot version occurs, creating a common sandstorm. In the north the Haboob is colder and causes less dust storms than in the South.
The Haboob also occurs in the southwest of the US.
Especially in the dry states, suchs as Texas and Arizona.
The photo above is from Lubbock, Texas. This haboob looks really scary, but fortunately it doesn't last long. However, it can wreak havoc in those hours.