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The 1930s Dust Bowl Drought (DBD) in midcontinental North America was a severe environmental event, with large-scale farm failures and ∼500,000 residents displaced during a global depression. Drought conditions were initiated with mode changes in ocean circulation including Pacific Ocean cooling and North Atlantic warming, and concomitant development of a persistent high-pressure ridge over western U.S., weakening the Great Plains Low Level Jet. Drought conditions were further exacerbated by the expansion of cereal crops in the 1920s and drought denudation in the 1930s which increased surface albedo, and decreased evapotranspiration, convection and precipitable moisture. The increase in bare sandy surface soils increased dust loads, which further extended the footprint and severity of the DBD. Agricultural census and remote sensing analyses of 1930s aerial photography show that only 30%–35% of the DBD area was cultivated, consistent with the broader Great Plains, and less, 10%–15% on the western edge. In situ dust emissivity experiments show that there are multiple sources of dust from cultivated and uncultivated surfaces, depending on vegetation and soil conditions. The DBD had >100 dust storms/year lasting hours to days with visibility <100 m, with corresponding PM 10 concentrations >5,000 μg/m 3 , posing a severe health risk. This dust storm occurrence was broadly analogous to contemporary dust events for the most arid areas in Asia and Middle East. DBD dust storms occurred under anticyclonic circulation, predominance of southward meridional flow, with reduced moisture flux from oceanic and gulf sources. Future droughts may be more severe with greater climate variability and hydrometeorological deficits reflecting added drought severity from greenhouse gas warming with new dust sources across the Great Plains, though potentially mitigated by extreme intervening wetter periods, continued irrigation and vegetation changes that can locally enhance evapotranspiration.