A 14-month-old girl has died in Long Island after police said her grandmother had forgotten to drop her off at a daycare center — and instead left her alone inside her sweltering hot SUV for eight hours.

Suffolk County police officers were called to Redwood Lane near the Long Island Rail Road station in Smithtown around 4:20 p.m. Monday for a report of an unresponsive child.

The toddler was rushed to Saint Catherine of Siena Medical Center, where she died.

An investigation has determined that the baby’s grandmother, a 54-year-old woman from Greenlawn, was supposed to take her granddaughter to a daycare Monday morning

Instead, the woman headed straight to work, “leaving the child in a car seat in a back seat,” the Suffolk County Police Department said in a press release.

About 8 hours late, the grandmother went to pick up the tot at the daycare on Redwood Lane, only to realize that she had left her grandchild inside her maroon 2018 Jeep Cherokee.

The grandmother, who has not been named, was not charged in the girl’s death on Tuesday. But police told The Post the investigation is ongoing.

Temperatures in Smithtown reached 83 degrees during the day Monday, according to AccuWeather.com.

When the outside temperature is around 80 degrees, the in-car temperature could reach a scorching 123 degrees after just one hour.