It happened about 8:30 p.m. Wednesday on Highway 50 in Benson.
Police said Catherine Renee Hayes, 50, was walking along the road when the car hit her.
The driver remained on the scene and was cooperative, police said.
Investigators blamed patchy fog and Hayes dark clothing for obstructing the view of the driver.
The driver was not speeding, and investigators do not expect to file any charges against the driver.
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