A preliminary investigation shows the 26-year-old -- missing since July 10 -- was driving on Woodhaven Road, near where improperly negotiated a curve, went down to the culvert, airborne, up and over a guardrail and crashed into a tree 30 feet into the air, CBS3 reports.
She is believed to have been ejected through the sun roof, and flooding from a July 12 storm may have moved her body to a nearby creek, authorities told the outlet.
Johnston's boyfriend Mike Bastik penned a heartbreaking tribute to her on Facebook Sunday, hours after her body was found.
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