(CNN) The US is facing a major heat wave in the coming days, with two-thirds of the country at risk. The Northeast and Midwest are expected to be hit the hardest, with the heat index expected to reach nearly 115 degrees in some parts of the country.

Officials in the affected areas are warning people to stay cool and hydrated, and of course, not to leave children or animals in hot cars. According to the National Safety Council, an average of 38 children die every year after being left in hot cars.

To demonstrate the danger, staff from the National Weather Service in Omaha, Nebraska, attempted to bake biscuits in the back of a car using only the heat from the sun.

The National Weather Service in Omaha put unbaked biscuits in a car to demonstrate how hot it could get inside.

"If you are wondering if it's going to be hot today, we are attempting to bake biscuits using only the sun and a car in our parking lot," NWS Omaha said on Twitter on Friday. "We will keep you posted with the progress."

The team placed four biscuits on a baking sheet on the dashboard of a car and left it to sit under the sun. After 60 minutes, the pan reached 175.2 degrees and the tops of the biscuits reached 153 degrees. The back seat registered 120.4 degrees in the shade.

Biscuits are starting to get a slightly golden tinge to them. pic.twitter.com/ptL24RHQfs — NWS Omaha (@NWSOmaha) July 18, 2019

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