FRISCO - It's a warning that's hard to miss.
Flashing across billboard-sized electronic signs from Denver to Frisco and back, the new message offering advanced notice of the weekly traffic nightmare on eastbound Interstate 70 Sunday afternoons is reaching drivers loud and clear.
In the weeks since the new messaging has been posted, projecting a two-plus-hour commute to Denver during specific time windows, drivers have reacted accordingly, leaving earlier or later and spreading out congestion.
"It appears to be working," Colorado Department of Transportation engineer Peter Kozinski said of the new messaging. "We haven't had to meter at the Eisenhower Tunnel recently. People seem to be spreading their peaks out a little bit."
Vehicle counts recorded at the tunnel on recent Sundays tell the same story.
At 10 a.m. on the first Sunday in August, there were 500 more cars on the road than the same time on the first Sunday in August, 2011. But at 3 p.m. the same day, the number of cars recorded fell to 1,411 - from more than 2,400 at the same time and date last year. As the day wore on, traffic picked up again. At 9 p.m. the same day, there were 980 cars recorded at the tunnel, compared to 880 cars last year.
"The traffic was heavy at 8 a.m.," said Breckenridge business owner Ken Nelson, who traveled to Denver Sunday. "I'm getting to the Twin Tunnels where there is a lot of backup ... It was surprisingly heavy in there. It wasn't bumper to bumper, but it was definitely 35 mph."
CDOT has tweaked the messaging on the signs from earlier this summer, when they warned of three-hour delays for the better part of the day on Sundays.
Subsequent postings have projected only two-hour delays and shrunk the heavy traffic window from late morning through mid evening to 1-5 p.m.
"We're trying to find that balance," Kozinski said. "We want to let people know there can be delays if they try to return during the peak hours on Sundays, but in the same vein, we're definitely not trying to discourage people from coming to the High Country."
The heavy-traffic time windows posted on the electronic signs were changed after CDOT officials looked more carefully at the timeframe that saw the worst congestion in the past.
Still, local officials expressed concern that the signs were chasing Sunday business back down the hill earlier.
"Certainly, we'd like them to message people in regard to how (traffic) happens on the road, but maybe not direct them to leave so early," Breckenridge Town Councilwoman Jennifer McAtamney said. "I'd rather see them ask people to stay later. If you leave at 2 p.m. it's going to be a three-hour trip to Denver. If you leave at 6, it's going to be your usual hour-and-a-half and you get to have a nice dinner in town."
Lodging representatives in Frisco and Breckenridge said they haven't noticed a big uptick in early check-outs, and some business owners say they're not worried about the impacts.
"I felt like it encourages people to stay around later," said Nelson, who owns restaurants in Breckenridge. "I think frankly people are going to spend their Sunday playing and I hope they appreciate the fact they're getting a heads up that it's going to be bad."
CDOT officials say they have not yet decided whether similar messaging will be posted during the winter.