Hot days make for hotter cars
By Jared Shelton News-Press NOW meteorologist
After a blistering end to July, heat is continuing to make headlines across the heartland with the start of August, perhaps unsurprisingly, as late summer is prime time for slow-motion heat waves to roll across the central United States.
This season has certainly delivered thus far, especially over the past week, with heat-related alerts posted from the Gulf Coast to the Dakotas for several days consecutively. In fact, all of the mid-Missouri River Valley was under Excessive Heat Warnings through the final days of July, the highest tier of heat-related alert.
Excessive Heat Warnings and Heat Advisories serve to bring attention to the dangers of high temperatures and oppressive humidity, which can result in extreme heat indices. The criteria set in place for the issuance of these messages are based on outdoor temperatures and heat indices. However, temperatures within enclosed spaces without ventilation, such as automobiles, can quickly eclipse outdoor temperatures by 20 degrees or more.
To test how quickly temperatures rise inside a car on a hot summer afternoon, I placed an old-fashioned mercury thermometer on the back seat of my vehicle on a 95-degree day. The car was parked in an open lot without shade, but the thermometer was not in direct sunlight. For the sake of being realistic, I also cracked the sunroof for a bit of ventilation.
At 3:07 p.m. the temperature read 95 degrees. By 3:13 p.m., the mercury was surpassing 110 degrees, and by 3:17 p.m., the thermometer read 120 degrees. That’s a full 25-degree temperature increase in only 10 minutes! Because my thermometer stopped at 120 degrees, longer increments of time were not able to be tested, although they most definitely can lead to temperatures as extreme as 130- to 140-plus degrees over longer time spans.
It may seem like common sense that scorching hot car temperatures can be dangerous, yet over 900 children have died inside hot automobiles across the U.S. since 1998, according to the National Weather Service. While most deaths were due to children being left in hot cars, some resulted from children accessing parked cars without supervision.
In addition to all of the typical heat-related precautions like hydration, shade, lightweight clothing and circulating air, always look before you lock. That goes for children and pets as well, which can also succumb to extreme heat inside vehicles quicker than you may think.
Notably, it’s important to understand that hot car deaths are not reserved for the hottest of summer days. The National Weather Service has found that roughly one-third of hot car deaths in the U.S. occur outside the summer months, when outdoor temperatures are toasty and not necessarily extreme.
