TUESDAY, Dec. 28, 2004 (HealthDayNews) -- As anyone who's tried to navigate the roads during a winter storm knows, snow spells trouble for drivers. But not every stormy day is equal: New research suggests that drivers face the most danger on the first day of snowfall.
"It's quite a bit more dangerous in terms of crashes of all severity levels," said study co-author Daniel Eisenberg, an assistant professor of health management and policy at the University of Michigan. Senior citizens are at especially high risk -- they're more than 30 percent more likely to get in an accident during the first snowfall of the season compared to other snow days.
However, researchers found that there are actually fewer fatalities on snowy days than on good-weather days, perhaps because fewer people drive when it's snowing.
According to federal statistics, bad weather contributes to about a third of all crashes and 20 percent of fatal highway wrecks, accounting for an estimated 7,000 deaths a year.
Eisenberg and colleagues examined federal accident statistics from 1975 to 2000 and linked the 1.4 million fatal crashes to weather conditions in the 48 states where they occurred. (Alaska and Hawaii were not included in the study).
The findings appear in the January issue of the American Journal of Public Health.
Researchers found that fatal accidents were 14 percent more likely on the first snowy day of the season compared to subsequent ones. However, fatal accidents were 7 percent less likely on snowy days compared to good-weather days. But when researchers looked at 17 states in the 1990s, they found that nonfatal accidents were more common when it snows.
Why the discrepancy -- fewer fatalities but more nonfatal accidents on snow days?
"The most obvious answer is that people are driving a lot slower, so the consequences of getting in a crash are much less severe on average," Eisenberg said. Also, while the study didn't look at the number of people on the road, "it's undoubtedly true that there are fewer people on the road when it snows. That's another reason why fatal crashes go down."
At the time of the first snowfall, drivers may not have had time to change their habits, he added. "It may take a couple of snowfalls for people to start curtailing their driving," he said.
It's no secret that snow makes driving more difficult. But people don't always realize just how much harder it is and may assume that features like antilock brakes will protect them, said Tim Hurd, spokesman for the National Highway Traffic Safety Administration.
"They help you control the car better and steer, but you're not able to stop any quicker," he said, which is an important thing to remember on slick, icy roads.
"There's no substitute for reducing speed. If the conditions get too bad, just get off the road," he added.
Eisenberg said the study findings suggest that officials need to give people more warning about the hazards of the first snowfall of the year.
"Maybe we should consider having electronic signs that alert people of the elevated risk on those days," he said, adding that driver education programs could also include information about potential hazards.
Russ Rader, spokesman for the Insurance Institute for Highway Safety, emphasized that caution isn't just for snowy days.
"Most fatal crashes happen when the weather is fine," he said. "Deaths from crashes go on relentlessly every day."
Get tips about driving in the snow from the Wisconsin Department of Transportation.