Three-year-old Sera Okutani died Saturday after being left alone in a car for more than 1 1/2 hours while her father visited friends at a Pi'ikoi Street apartment, police said, a tragedy child-safety advocates say should not have occurred.

An autopsy today is expected to find cause of death to be hyperthermia-related. The Honolulu medical examiner's office identified the child yesterday.

"The death of the child left in a vehicle in Honolulu was the first in the nation this year but sadly far from the last," said Jan Null, adjunct professor of meteorology at San Francisco State University, who has been actively researching the issue of how hot vehicles get as well as monitoring the tragic instances of children left in hot vehicles.

Although Sera's case is classified by police as an unattended death, it comes under the jurisdiction of homicide investigations.

Detective Ted Coons, acting head of Honolulu police homicide investigations, said the child was left in a booster seat inside her father's car for about an hour and 40 minutes. The father returned to find his daughter unresponsive.

The child was taken to a hospital, where she was pronounced dead. Sera reportedly suffered from cerebral palsy.

Police do not suspect foul play and say there was no immediate indication of a history of child abuse or substance abuse on the part of the father at the time of the child's death.

"It's just very tragic," Coons said.

The National Weather Service's recorded temperature at 2:08 p.m. Saturday at Honolulu International Airport was 81 degrees. Sera was in a car at Makiki, where the temperature was likely a few degrees cooler.

"With a high temperature of approximately 81 degrees, the temperature inside the vehicle would have reached about 115 degrees after 30 minutes and more than 130 degrees after an hour," Null said.

Janette E. Fennell, founder/president of Kids and Cars, a Kansas-based national nonprofit organization dedicated to preventing injuries and deaths that occur when children are left unattended in or around motor vehicles, called the death "truly heart-wrenching but preventable."

Fennell added that children left alone in vehicles have died from being strangled by a power window, inadvertently knocking a car into gear, carbon monoxide poisoning, falling out of a car and being run over, choking on a toy, and from being kidnapped.

Twenty-nine children in the United States died in 2006 after being left alone in vehicles, according to Kids and Cars.

Kids and Cars is supporting legislation introduced by Rep. Marilyn Lee, D-38th (Mililani-Mililani Mauka), to raise public awareness about the dangers of leaving children unattended inside motor vehicles.

Fennell said police now have only two choices when a child is found alone in a vehicle: Find the parent or caregiver and give them a "scolding" or take the child from the parents and turn them over to child protective services, and charge the offender with child endangerment or neglect.

"A scolding will probably not change the dangerous behavior, and the child endangerment or neglect charge may seem too harsh," Fennell said.

House Bill 356, which has advanced from the House Transportation/Judiciary Committee and will be voted on by a similar Senate committee today, would allow an offender to be cited by police, giving the community an opportunity to educate them on the dangers of leaving children alone and unsupervised in motor vehicles.

Reach Rod Ohira at rohira@honoluluadvertiser.com.