After Montana’s Record Heat: Crucial Car Safety Tips

Billings reached 111 degrees on Sunday, breaking the city's previous all-time record of 108 degrees set in 2002, according to the National Weather Service's daily climate report. Miles City topped out at a preliminary 115 degrees, shattering its own old mark of 111 set in 2012. Cities all over the state experienced extreme heat, and forecasters expect highs in the upper 90s to low 100s through Monday and Tuesday before any real relief arrives.

Heat like we had the last couple of days doesn't just make driving miserable. It puts real strain on tires, cooling systems, and batteries, and it raises the odds of getting stranded at the worst possible time.

How Extreme Heat Affects Tire Pressure and Car Safety

For every 10-degree jump in temperature, tire pressure increases by about 1 PSI, according to AAA. During a heat wave like the one we just experienced, that can add up to roughly 5 PSI of extra pressure, enough to push properly inflated tires into overinflation, which wears tread unevenly and can affect handling. AAA recommends checking all four tires, plus the spare, when they're cool rather than right after driving, and adjusting to the pressure listed on the driver's door jamb rather than the number printed on the tire itself.

Checking Car Coolant and Engine Fluids to Prevent Overheating

AAA advises flushing and refilling coolant on the manufacturer's recommended schedule, typically every two to five years, and checking hoses and belts for cracking or soft spots before a heat wave hits, according to AAA. Low coolant or degraded fluid reduces the engine's ability to shed heat, which raises the risk of a roadside breakdown on a day when sitting on the shoulder is its own hazard.

What to Pack in a Summer Car Emergency Kit

AAA recommends keeping extra water and snacks in the vehicle for everyone riding along, including pets, as well as a charged cell phone, in case of a breakdown or delay, per AAA's guidance. If your car overheats or you're stopped on the shoulder, AAA also recommends turning on hazard lights immediately and pulling as far off the road as possible.

The Danger of Hot Cars: How Fast Interior Temperatures Rise

On an 80-degree day, a car's interior can reach 99 degrees in the first 10 minutes and 123 degrees within an hour, according to research cited by the Arkansas Center for Health Improvement. Rolling the windows down or parking in the shade does little to slow that rise, according to NHTSA's heatstroke prevention campaign. A child's body temperature climbs three to five times faster than an adult's, and heatstroke can begin once core body temperature hits 104 degrees. NHTSA reported 31 child heatstroke deaths in vehicles in 2025, bringing the total to more than 1,000 since 1998.
Never leave a child, senior, or pet alone in a parked car, even for a minute or with the windows cracked.

Best Ways to Cool Down a Hot Car Quickly

Before running the air conditioning at full blast, open the doors on one side of the vehicle first, then use the door on the opposite side to fan out the trapped hot air. Once you're driving, switch the air conditioner to recirculate mode so it cools the air already inside the cabin rather than pulling in more hot air from outside. A windshield sunshade and parking in the shade when possible both help keep the interior from reaching peak temperatures in the first place.

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If you're heading out anywhere over the next few days, checking tire pressure and coolant levels before you leave takes a few minutes and can be the difference between a normal drive and a call to roadside assistance in triple-digit heat.