NAPA (CBS SF) — Napa police issued a warning Monday to local pet owners about the dangers of leaving dogs inside vehicles during the current heat wave.

Authorities said a dog was spotted inside a parked car at the South Napa marketplace on Sunday while the temperature outside was soaring into the triple digits.

They called 911 and Napa police and an officer from the sheriff’s department’s animal services division responded and freed the dog from the car.

A check of the temperature inside the vehicle with a thermometer registered a stifling 136 degrees.

The dog was taken to a local vet where it was under observation. The incident remained under investigation.