Snow and ice make winter driving hazardous, especially along I-235 and I-35/I-80 near Des Moines. However, Iowa’s traffic statistics reveal a surprising contrast: Warmer months can see fewer crashes, yet summer can record more traffic deaths.
Understanding the difference between crash frequency and fatalities can help you recognize the dangers of driving in either season.
What do Iowa’s seasonal crash statistics reveal?
A study of 728,442 Iowa crashes from 2009 through September 2022 found that spring and summer averaged about 15% fewer crashes than fall and winter. Crash numbers also varied more from November through February, likely due to severe weather.
However, Iowa Department of Transportation data reveals a different pattern in traffic deaths. In 2025, the state recorded 90 fatalities during summer, including 26 in June, 28 in July and 36 in August. By comparison, January and February each recorded 17 deaths, while December had 11, totaling 45 across the three winter months.
Summer recorded twice as many deaths as the selected winter months. These figures compare months within one calendar year and do not establish which season had a higher fatality risk per mile traveled.
Why do driving hazards differ between seasons?
Summer and winter create different risks on Iowa roads. During warmer months, you may encounter:
- Heavy traffic: Vacation travel can increase congestion, particularly along I-80.
- Speeding: Higher speeds increase the risk of severe injuries and fatal crashes.
- Construction zones: Lane closures and sudden stops can create hazards near Des Moines interchanges.
Winter presents different challenges, including:
- Snow and ice: Slippery pavement reduces traction and increases stopping distances.
- Poor visibility: Snowstorms can make nearby vehicles and road hazards harder to see.
- Icy bridges: Overpasses can freeze before surrounding roads, creating unexpected hazards.
Higher-speed collisions involve greater impact forces, increasing the risk of fatal injuries. Although drivers may slow down during winter storms, icy roads can cause crashes even at low speeds. These differences help explain how crash frequency and severity can vary between seasons.
What should you remember about seasonal crash risks?
Iowa’s statistics show why both seasons deserve your attention. Adjusting your speed, maintaining a safe following distance and checking road conditions can help reduce your risk.
If you suffer crash-related injuries, legal guidance can help assess possible negligence and explain your options for seeking compensation.