On Thursday, Wyoming, North and South Dakota, and Minnesota endured blizzard conditions that included heavy rain in some places. Flooding, hail and strong winds also were reported in parts of the two states.
The storm also contributed to the death of Daniel Groves, a Colorado State Patrol officer who was hit and killed by a auto as he helped another driver who had slid off Interstate 76 near Denver. He police said people should be careful during the exit. "It's best, very honestly, to stay home".
Lew warned drivers that conditions would remain precarious at least through Thursday.
On Wednesday up to 1.2 meters of snow and 170-km-per-hour winds blasted Colorado, leaving thousands of motorists stranded and tens of thousands of people without power in Colorado and Texas.
The window-rattling storm brought blizzards, floods and tornadoes, stretching from the northern Rocky Mountains to Texas and beyond. "We're looking at something that will go down in the history books".
Highways were also closed in the Nebraska Panhandle, South Dakota and near the Wyoming border on Thursday due to the storm. And while some flights resumed, the airport was not expected to be fully operational until midday on Thursday as airlines had still had to dispatch more planes to Denver to replace those diverted or canceled earlier, she said.
A day earlier, the blizzard prompted the cancellation of more than 1,300 flights at Denver International Airport, closed government offices, schools and businesses and was blamed for the death of a state trooper. Xcel Energy spokesman Mark Stutz said zero visibility made conditions hard for fix workers, and it could take days to restore power to everyone. And in New Mexico, 36 miners at a nuclear waste repository were trapped underground in an elevator for about three hours because of a power outage caused by the extreme weather.
It was caused by a combination of the jet stream and normal conditions in the wind shadow of the Rockies. "This can happen when a cold air mass collides with a warm air mass, such as air over warm ocean waters", stated the National Oceanic Atmospheric Administration.
"It's like a vacuum cleaner, really", Carbin said. When that much air rushes higher into the atmosphere, it causes severe weather.
Because of the rapid drop of pressure associated with a bomb cyclone, tornado watches have been issued in parts of Arkansas, Mississippi, and Tennessee.
As millions of Americans feel the brunt of a powerful, late season storm, climate experts said the sudden blizzard was no fluke, but a sign of things to come.
A tornado in New Mexico sheared roofs off buildings in the small town of Dexter, about 200 miles southwest of Albuquerque.
"It is a tragic reminder that people's lives are at stake". A dairy euthanized about 150 cows injured by the tornado. At least one tornado was confirmed in the MI community of Vernon, between Lansing and Flint, which damaged at last two homes, snapped numerous telephone poles and ripped a metal roof off of a building according to the U.S. National Weather Service.