It happened just before 1:30 p.m. on Thursday, Aug. 8 in Smithtown.
The woman, 79-year-old Patricia Schmidt, was driving a 2001 Honda Accord, making a right turn out of the parking lot at Stop & Shop at 291 West Main Street (Route 25) to head westbound, when the vehicle veered off the roadway, Suffolk County Police said.
The car then went down an embankment and into the woods, said police.
Detectives believe she may have suffered a medical event.
Schmidt, 79, of Elayne Court in Smithtown, was transported to St. Catherine of Siena Medical Center in Smithtown where she was pronounced dead.
The Honda was impounded for a safety check.
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