Tuesday morning's commute is expected to be sloppy, thanks to a spring snowstorm that forecasters said has the potential to dump up to a foot of snow in the Boulder area.
And St. Vrain Valley, Adams 12, Denver Public Schools and at least four other Front Range school districts on Monday night had already declared Tuesday as a snow day.
The University of Colorado announced Tuesday morning that it would not shut down the Boulder campus, and, as of 5:40 a.m. Tuesday, the Boulder Valley School District has not announced any closures or delays.
The National Weather Service issued a winter storm warning that's in effect through Tuesday night.
The temperature in Boulder dropped rapidly, from the afternoon high of 62 degrees to 32 degrees by 10 p.m. Rain turned to snow overnight Monday.
How much snow Boulder and other areas get will depends on how quickly the snow started and where the predicted brief periods of heavy snowfall end up, said Boulder meteorologist Matt Kelsch.
He said the forecast for Boulder is 6 to 12 inches by Tuesday evening, with the higher end being more likely. The same holds true for Broomfield and Louisville, while Lafayette and Longmont may see less. Nederland is expected to get at least a foot.
Overnight, according to the National Weather Service, there was the potential for a brief period of heavy snowfall and near-blizzard conditions, with an inch or more of snow falling an hour. Tuesday, the forecast calls for steady and more widespread snow.
Because the temperatures are expected to be in the teens and low 20s, the Weather Service warned that travel will be dangerous as roads may become icy and snowpacked with blowing and drifting snow. Visibility also may be reduced to less than a quarter-mile because of snow and blowing snow.
"The morning commute will be the worst," Kelsch said. "People should expect the morning commute to be pretty messy."
While it's likely the sun will have a chance to melt some of the snow during the day, he said, any water and slush is likely to freeze quickly once the sun goes down. High winds also are forecast.
He said this spring storm will be colder than most, with highs in the 20s Tuesday. Overnight Tuesday, he said, temperatures could drop into single digits.
At Denver International Airport, the airlines reported a total of 26 flight cancellations Monday. A few flights due to arrive at DIA were diverted to Colorado Springs on Monday night due to the high winds.
Tuesday's forecast calls for 3 to 5 inches of accumulation, with snow generally ending by evening. New snow accumulation of less than a half inch is predicted overnight. Wednesday's forecast calls for partly sunny skies with a high near 38.
The University of Colorado planned to tell faculty members and students by 5:30 a.m. Tuesday if classes will be delayed or canceled with a text message to registered users and an online post at colorado.edu. If classes aren't canceled, CU officials said, campus employees can request the day off if "personal health or safety" is an issue.
The Conference on World Affairs panels will go on as scheduled at CU, unless the CU campus is closed because of the weather, according to organizers.
The Boulder Valley School District expected to decide on delays or closures by early Tuesday morning. Check for updates at bvsd.org.
As of 10:30 p.m. Monday, at least seven metro-area school districts -- St. Vrain Valley, Adams 12, Aurora, Cherry Creek, Douglas County, Jefferson County and Denver Public Schools -- had canceled classes.