In 1977, the San Joaquin Valley—the swath of agricultural land that runs through central California—was designated a disaster area. Record-low runoff and scant rainfall had created drought conditions. At the beginning of Christmas week, the weather was normal in Bakersfield, the city at the Valley’s southern end, but in the early hours of December 20th a strong wind began to blow from the Great Basin through the Tehachapi Mountains. Hitting the ground on the downslope, it lofted a cloud of loose topsoil and mustard-colored dust into the sky.
The plume rose to five thousand feet; dust blotted out the sun four counties away. Traffic on Highway 5, the state’s main artery, stopped. At a certain point, the anemometers failed; the U.S. Geological Survey estimated wind speeds as high as a hundred and ninety-two miles an hour. Windows on houses were sandblasted to paper thinness.
The Tempest from Tehachapi, as one researcher called it, spread dirt over an area the size of Maine. Twenty hours afterward, the dust reached Sacramento, four hundred miles north of Bakersfield, in the form of a murky haze that hung in the air for another day, stinging the eyes and noses of the residents. On the twenty-first, it started raining in Sacramento, which turned the dust to mud, coating the cars and sidewalks, and marked the end of the drought.
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