By Dana Ford and Holly Yan, CNN
(CNN) — The calendar may say spring, but the weather speaks for itself.
Winter storm warnings were in effect Sunday for areas in roughly half a dozen states, from Missouri on east to Pennsylvania.
It’s the same storm that has already rolled over parts of Kansas and Nebraska and is expected to continue barreling east, possibly as far as Washington, by Monday.
In many places, the storm starts as rain before temperatures cool and it changes to snow. Some places might even get sleet.
Add winds gusting up to 40 mph, and you get one wintry mess.
Stranded in St. Louis
The storm dumped at least 3 to 7 inches of snow in the St. Louis region, CNN affiliate KTVI reported, with more expected to fall.
The white stuff forced cancellations and caused delays at Lambert-St. Louis International Airport.
“Right now, it’s just going to be a long day, sitting around waiting. I’ve had one flight canceled and then rerouted, and that’s looking iffy if it keeps snowing,” Cathy Rutherford told KTVI.
Just to the northwest of St. Louis, in St. Charles, the storm was causing problems for travelers on the road as well.
Cars struggled on hills that proved too much for some drivers.
“It’s crazy. I’m just sick of all the snow. Like, I was so ready for it back at Christmas, but now I’m over it,” said motorist Jaci Nezum, the affiliate reported.
According to the National Weather Service in Pittsburgh, Pennsylvania, the storm will bring 4 to 6 inches of snow to the metro area. Elsewhere in the region, as much as 12 inches is forecast.
The heaviest snowfall is expected after midnight through dawn on Monday, which will likely spell hazardous travel conditions for the start of the workweek.
The heavy snow could also knock down trees and power lines.
“If you must venture out at all … use extreme caution,” the weather service warned.