How Do We Solve the Interstate Pileup Problem?

They happen again and again every winter season. Interstate pileups. But after the destruction, after the casualty report, and after the accident investigation is complete, the spotlight on these nasty weather-related accidents quickly fades. Outside of official documentation from the NTSB, there seems to be little follow-up discussion and reporting on why the pileup occurred and how it can be avoided in the future.

January 9, 2015 radar loop from southwest Michigan showing lake-effect snow bands flowing over I-94 (Credit: The Weather Channel)

Lake-effect snow squalls or frontal squalls are the main contributors to these awful multiple-vehicle accidents. Bands of snow develop quickly in varying snowfall rate intensity and flow over major state thoroughfares reducing visibility to near zero in a moment’s time.

Example of very poor visibility when driving in a snow squall

Driver error within the squall — anywhere from overly cautious driving to panic-stricken driving — can easily lead to a vehicular accident. Let’s call that initial accident, the “trigger.” Cars, buses, and tractor-trailers approaching the “trigger” all try to avoid the carnage by braking, swerving, or purposefully driving off the road. But with visibility so low, it’s just too late to take appropriate action and a massive chain-reaction of awful and sometimes deadly crashes occurs.

Credit: The Weather Channel

A recently published graphic from The Weather Channel states that cars traveling at 70 mph in snowy road conditions yields roughly 550 feet of braking distance. The necessary braking distance is simply too long when squall visibility can be next to zero. Stalled or stopped vehicles in front only become visible when you have already passed the braking distance threshold. It’s too late, you’re going to crash.

100–150 car pileup on Michigan’s I-94 on January 9, 2015

Some will say it’s strictly human error that causes the pileup. Others will blame the weather conditions as the number one cause. It’s the combination of both. But are these pileups inevitable? Just another thing in this world we have to deal with and can’t avoid? I don’t think so and I believe there are solutions.

Solving the Problem

There needs to be some sort of enhanced relationship among the local offices of the National Weather Service and the state’s Department of Transportation. A relationship that includes perhaps a staff meteorologist stationed at the state DOT headquarters or at least one that is fully dedicated to travel conditions at the NWS local office during poor weather conditions. This close partnership could provide a way to quickly alert drivers in real-time of drastically changing weather conditions; such as a snow squall, thickening dense fog, or torrential rain from a passing summertime thunderstorm.

Solution Update 1 (Posted on 1/15/2015):
Since publishing, I've come to understand that many state DOTs are already closely working with meteorologists although not necessarily from the government sector but the private meteorology firm sector. Private companies like Weathernet and Meridian act as a 24/7 meteorological operations support for clients that depend on the weather forecast; i.e. construction companies, the aviation industry, and government agencies such as the DOT. So with this new knowledge, my point and solution remains the same. The close partnership providing nearly instantaneous weather knowledge already exists. Now let's take this potential life-saving information such as extreme poor visibility on a given stretch of interstate and act on it and transmit it to those that would benefit in a timely fashion.

Of course how to message the drivers is another communication hurdle but I think it’s one that could likely be solved in today’s advancing GPS, mobile, and car WiFi technology. An alert is transmitted to a car with internet capability within a specified GPS coordinate and a given outward radius.

A less-sophisticated communication technique would involve the addition of numerous DOT signs along roadways of known poor-visibility problem areas that would flash and alert the driver that danger lies ahead. Yet another less sophisticated but intriguing idea would to line roadways with track lighting (similar to road reflectors) that would light up red or blue or whatever color when an immovable and stopped obect(s) is blocking the roadway up ahead. That latter idea came from the January 13th episode of the “The Boomer and X” podcast (31 min 20 sec mark).

Diagram of moving object detection from Nissan (Source:

Outside of quick communication, another solution is to look toward car technology such as Nissan’s “moving object detection.” Of course in this scenario we would be talking about “massive roadblock detection”. At the recent 2015 Consumer Electronics Show convention, object detection and self-driving cars were popular topics and both will continue to be in the coming years. I believe it’s this technology that could potentially be manipulated to offer not just near-object detection but also detection that will surpass the aforementioned braking distance threshold. Detection that could save countless lives.

Solution Update 2 (Posted on 1/15/2015):
Since I’ve published this article, I’ve become aware that people are in fact working on solutions! One person in particular is Sheldon Drobot who works at NCAR as a scientific program manager. His specialty includes the impacts of weather on roadways and surface transportation systems. He recently was interviewed at the 2015 AMS Annual Meeting in Phoenix, Arizona. I highly recommend viewing his interview.
After years of research, he and his team are getting closer to bringing a device or mobile app (or both) to the the car manufacturer and the driver (consumer) — a vehicle data translator (VDT). The VDT will collect data from the car including wiper blade movement and ABS/traction sensors and transform that data into actionable information such as VDT-based weather alerts. Alerts that would notify the driver of imminent weather hazards and provide re-routing alternatives. I look forward when this sensor capability enters into our passenger vehicles.
Slide from NCAR “Connected Vehicles and Weather” Presentation
Slide from NCAR “Connected Vehicles and Weather” Presentation