As a spring snowstorm barreled toward Denver on Thursday, airlines canceled more than 140 flights scheduled to arrive at or depart from DIA that evening and Friday morning.
The only problem: The storm skipped over the Mile High City, meaning the flights likely could have gone ahead as scheduled. In the meantime, an estimated 10,000 passengers were left trying to reschedule their flights.
Is this the new airline policy in which flights are canceled at the hint of snow? And how does this bode for a city that can often be blanketed in snow?
"There is no exact science to canceling flights," said Darryl Jenkins, a Virginia-based airline consultant. "You can never forecast with 100 percent accuracy, so this becomes an incredible experiment in making decisions under uncertainty."
Airlines, heavily criticized this winter after several high- profile incidents in which passengers were stranded on planes for hours and at airports for days, admittedly are increasingly canceling some flights ahead of potentially severe storms, industry observers say.
The strategy can help airlines minimize weather disruptions. But this week's example in Denver shows it doesn't always work as planned, highlighting the fine line airlines walk in such situations.
Airlines say the strategy, which they call canceling flights "proactively," helps thin out crowds and ease congestion when a severe storm does hit.
"When we take out nine, 10 flights in the same time frame, we have more flexibility if there is a weather event," said Frontier spokesman Joe Hodas.
It saves some passengers a trip to the airport if there's a high probability their flight will be canceled. And it helps carriers position their planes in other cities - rather than getting stuck at a particular airport - allowing them to recover more quickly when the storm lifts.
But airlines will always have to deal with an element of uncertainty.
On Thursday, United proactively canceled 80 evening flights into and out of Denver - before the first snowflake fell. It also grounded 40 flights scheduled for Friday morning. Frontier axed 18 Friday morning departures and arrivals, and other airlines bagged a handful of flights as well.
The Denver area, though, received just a light dusting -midafternoon on Thursday.
The difficulty, aviation officials say, was that weather projections were all over the board.
"I don't know that anybody agreed on what this storm was going to look like," said DIA spokesman Steve Snyder. "Some forecasts said we might get 6 to 8 inches, others said a foot or more."
Denver has had several storms since the December blizzard and subsequent big storm without any major disruptions at the airport. This week's near miss wasn't expected to be a run-of-the-mill storm.
Even so, the cancellations represent only a fraction of the roughly 3,000 daily departures and arrivals scheduled at DIA over the two-day period. And the carriers said most - if not all - passengers were rebooked on flights Friday.
Airlines will feel a financial impact, although it will be minimal relative to the size of the companies. United's canceled flights could cost the company $1.5 million, while Frontier could take a $342,000 hit, according to some estimates.
Observers also say airlines have become extremely cautious after a winter in which they came under fire for how they handled some storms.
In Denver, thousands of passengers were stranded at DIA in December after their flights were canceled amid back-to- back storms, one of which closed the airport for nearly two days.
"If we had anticipated that the airport was going to close, we would've been a lot more aggressive at proactively canceling flights," Hodas said. "As a result, we ended up canceling flights when we had passengers already at the airport."
United was to open its check-in area at 2 a.m. today, about two hours earlier than usual. It's also putting plans in place to fly workers into Denver from other hubs.
The state's response to every major storm has to be evaluated to assure access to Colorado's signature winter playgrounds.
After a 20 year absence due to high fees, Southwest is again flying from DIA.