A Burlingame mother left her 2-year-old son in a 125-degree vehicle Thursday with only a two-inch gap in one window while she dashed into a grocery store, according to prosecutors who charged her with one felony count of child endangerment.

Barbara Stepaniuk, a Burlingame resident from Poland, was arrested outside the Redwood City grocery store after passers-by heard a child crying from a white Chevrolet Corvette with black interior and its top up, said Chief Deputy District Attorney Steve Wagstaffe.

One of the people reached an arm into the car through a two-inch gap left in one window and was able to free the baby boy who was strapped into a car seat. Medics called to the scene declared the child medically fine but officers found the temperature inside the vehicle alarming. The outside temperature was 92 degrees while inside the vehicle — a measurement taken 10 minutes later — was 125 degrees, Redwood City police reported.

Stepaniuk told police she was gone for about 20 minutes.

Prosecutors charged Stepaniuk with felony child endangerment, a charge that can carry up to six years in prison. She has no prior criminal convictions in San Mateo County.

On Friday, Stepaniuk pleaded not guilty and Judge John Schwartz set bail at $50,000. By the end of the day she was still in custody.

Stepaniuk returns to court Sept. 5 for a Superior Court Review conference followed by a preliminary hearing Sept. 13.

Michelle Durand can be reached by e-mail: michelle@smdailyjournal.com or by phone: (650) 344-5200 ext. 102.