It's the commuter's constant question: Stay the course despite the traffic jam or stray in search of a faster route?

Winter weather only ups the ante.

Routine and gut instinct, plus a well-timed radio traffic report, used to be our guides.

Then the smartphone-turned-navigator came along, giving us real-time traffic updates with the tap of a touch screen. Apps like Waze and Google Maps highlight the fastest routes based on traffic data, while MnDOT's 511 app posts traffic and road conditions.

But computers aren't always the best co-pilots, especially in a Minnesota snowstorm. The technology can provide a nifty snapshot of the present, but can't say with absolute certainty what will come next.

Elisa Poquette found that out on a recent snowy morning. According to Google Maps, her trip from south Minneapolis to her Wayzata office should have taken 45 minutes.

"It took me over an hour just to get to the basilica," she said. "It was just absurd how wrong it was."

So is our faith in such apps misplaced? Our hope for technology too high? Will we be stuck in traffic forever?

"[Apps] can tell you what may happen in the near future, assuming that nothing out of the ordinary takes place," said John Hourdos, director of the Minnesota Traffic Observatory. "During your trip, a billion unexpected things can happen that are going to push your experience out of the ordinary. It's quite unpredictable, bottom line."

Inside the apps

The Minnesota Department of Transportation has been tracking traffic in real time for decades. The department uses sensors on freeways and many state highways in the metro area to figure out where traffic's moving and where it's jammed.

Construction updates, road conditions (reported by snowplow drivers), plus hazards or crashes reported by the State Patrol have long been available to traffic reporters and the general public by calling 511 or checking www.511mn.org.

That wealth of public data is often the basis for other navigation apps.

Google Maps, which displays real-time traffic flow with red, yellow and green lines, also draws data from the GPS coordinates of Android phone users who have opted to anonymously share their locations.

Waze, purchased by Google last year for a reported $1 billion, is even more fervent about crowdsourcing. Its millions of users worldwide, all tracked by their phones' GPS, update the Waze map in real time just by driving. They can also report specific incidents, from slow traffic to police car sightings, with voice commands. Waze added the hands-free controls so people wouldn't be tapping while driving. The MnDOT 511 app asks users to agree not to use it while driving.

Before setting out on snowy mornings, Diane Kulseth checks three different apps.

She uses MnDOT for winter road conditions, Google for a quick overview of traffic flow and Waze to pick a route from her home in Maplewood to work in Eagan, based on travel time.

"It's been a little bit of a tossup. There have been a couple times where it's been great and I've ended up cutting off a good chunk of time," she said.

Yet even without a 100 percent success rate, Kulseth recommends Waze to friends. "The more people use it, the better it will get," she said.

Better than nothing

Waze had nearly 50 million users when Google bought the Israel-based app in July. Julie Mossler of Waze said there are about 200,000 registered users in the Twin Cities. That doesn't mean they're all active, but she said the area is relatively well-populated, and therefore keeps maps up-to-date.

But sometimes people would just rather get their traffic updates from a real human.

Ken Olson, who does on-the-air radio traffic reports for 1500 ESPN My Talk 107.1, boasts nearly 8,000 Twitter followers who pepper his @MSP_Traffic account with inquiries.

"I receive tweets from people in bed. I receive tweets from people just leaving, especially in the afternoon," he said. " 'How's the drive in St. Paul look? How's the drive in Bloomington look?' "

He bases most of his tweets on the information provided by MnDOT, with occasional updates from people who report from the road.

While tech-fueled traffic updates aren't always accurate, they can help people adjust their expectations, said David Levinson, a civil engineer at the University of Minnesota who specializes in transportation.

"If it's going to be 15 or 30 minutes because of some incident and you can't change it, then you can notify people or feel much more comfortable about accepting it," Levinson said. "You feel better about the situation when you have more information about it."

But sometimes more information about one traffic jam can lead to another elsewhere. If a lot of drivers opt for the same alternate route — suggested by Google, Waze or some other app — it may get clogged, too. The apps that update in real time will pick up on that secondary congestion, but not until it happens.

"The more people that you have listening to this information, the higher probability that they're all going to follow the suggestion of the computer and they're going to end up in the same place as everybody else and therefore creating [a new] problem," said Hourdos.

It's a Catch-22.

Still, he said, it's an improvement. Hourdos uses Waze when driving unfamiliar routes at rush hour. "Before, we were totally blind," he added.

But when the snow flies, Hourdos said, it's tough for an app to keep up: "Anything, especially anything with traffic lights, is not going to be a good choice — no matter what Waze says."

Katie Humphrey • 612-673-4758