Dust Storm 2011, Phoenix, Arizona

• 1930s: A series of dust storms displaced hundreds of thousands of agricultural workers in the central United States and Canada during the Dust Bowl.
• 1934: Just one of many notable storms in the 1930s, the storm of 9–11 May 1934 began in the far north-western Great Plains and proceeded east over the northern tier of states and parts of Canada and was notable for removing the vast majority of the soil deposited since the last Ice Age over some parts of its path.
• 1935: Another major dust bowl storm took place on April 14, which became known as Black Sunday.
• 1954-1991: The multi-year droughts in portions of North America of 1954-56, 1976–78, and 1987-91 were noted for dust storms of the intensity seen in the middle 1930s over some fraction of their coverage and timespan, and more sporadically during the times between. The three multi-year droughts were similar to the 1930s in storms being raised by synoptic scale weather events such as cyclones and cold fronts; otherwise the most common trigger is the outflow from convective activity, known as a haboob. Significant events of the latter variety occurred in Colorado and Kansas in May 2004 with winds to 100 mph, Minnesota and Wisconsin in June 2004 causing significant damage, and the upper Middle West in May 1988, notable for strong electrification and lightning activity and by one estimate reaching 30 000 ft or more. The first and third of this list reached black blizzard intensity, causing total blackout for some period ranging from 90 sec to 10 or more minutes, over some fraction of the ground covered. The 1987-91 drought was especially notable as in the 1930s for the large number of rain of mud events, often generated by dust in suspension and/or carried on upper-level winds.