The National Weather Service in Valley says steam generated by two Norfolk plants helped produce snow ended up traveling several miles to the south on Monday.
Meteorologist Brian Barjenbruch tells NewsRadio 1110 KFAB says the conditions were just right for the steam to add moisture and warmth to the ice already in the clouds. That produced a band of snow that stretched as far south as Seward on Monday afternoon.
"It just set up a scenario where this extra steam is able to produce a plume of snow and it's very similar to lake-effect snow that you might see around the Great Lakes."
Barjenbruch says the snow was in a narrow band about 20 miles wide that blew from Norfolk down toward Lincoln and Seward. He says the light snow and ice pellets that fell in Omaha on Monday was unrelated to the steam generated snow.
He says it's a pretty rare event, but has happened before. "There are even some meteorological research papers that have been written about it, even back in the 1970's, Barjenbruch says. "It's not terribly common, and the atmosphere has to be just perfect in terms of temperature and moisture."