Keli Cain of the Department of Emergency Management said Oklahomans are not used to heavy snow.
"In Oklahoma, we don't often get large amounts of snow like what we're seeing, especially up in northwest Oklahoma. We may get a couple of snows a year. So this is definitely not something that we're used to seeing," Cain said.
In preparation, many Kansas school districts already have called off today's classes, as has the University of Missouri-Columbia. And Kansas City, Mo., Mayor Sly James declared a state of emergency Monday.
All government offices and businesses across the region were closed and James urged residents to stay home if they could.
ABC News' Max Golembo, ABC News Radio and The Associated Press contributed to this report.