The polar vortex is headed southward once again, returning dangerously cold air to the Midwest and Northeast in the upcoming days.
The polar plunge that invaded the Upper Midwest on Monday will continue to spread across more of the eastern half of the U.S. through Tuesday night.
While temperatures will drop below freezing as far south as northern Florida on Tuesday night, the core of the cold will center on the Midwest and Northeast.
Highs will be held to the single digits and teens across these two regions once the frigid air takes up residence. Temperatures will even remain below zero during the daylight hours on Tuesday in and around Minnesota and the St. Lawrence Valley.
Temperatures dropping to at least 20 below zero over parts of Minnesota on Monday night, 10 below zero or lower is expected across the entire St. Lawrence Valley on Tuesday night. The entire state of Minnesota was reporting with below zero-degree temperatures by 2:30 a.m. CST.
Record high temperatures stretched across the Plains on Sunday, including in Lincoln, Neb., where it reached 66 degrees. But by 4 a.m. CST on Tuesday, the temperature was already below zero degrees. Temperatures are expected to drop another 5 to 10 degrees across the region.
The good news is that prolonged biting winds will not accompany this cold blast in the Midwest, preventing a repeat of the extremely low AccuWeather.com RealFeel® temperatures that were registered earlier this month.
The Northeast coast will have to endure an extended stretch of brisk and frigid winds in the wake of Tuesday's snow.
The magnitude of this cold blast is still dangerous enough to put residents who do not properly bundle up at risk for frostbite and hypothermia.
Care should also be taken to ensure that livestock and other animals housed outdoors have adequate shelter.
"The cold may be intense enough to cause school closings, frozen pipes and water main breaks," stated AccuWeather.com Expert Senior Meteorologist Alex Sosnowski. "Heating systems may struggle to keep up, people will spend more money keeping their homes and businesses warm and ice will again build up on area rivers."
The Alberta Clipper at the leading edge of the dangerous cold blast will spread snow from the Dakotas to the Ohio Valley, mid-Atlantic and southern New England through Tuesday.
A band of steadier and more disruptive snow will unfold along the spine of the Appalachians to, the Delmarva Peninsula, central New Jersey and Cape Cod. Washington, D.C., Philadelphia and New York City lie within this zone.
A couple of snow showers will even spread as far south as the North Carolina/Virginia border.
Beyond Wednesday, temperatures may slightly rebound, but frigid air should win out for the remainder of the month.
The next shot of arctic air due to reach the U.S. on Wednesday and Thursday will encompass more of the Plains than the early week blast.
Another visit from the Polar Vortex will deliver unseasonably cool air to the Midwest, preceded by rounds of thunderstorms, including severe weather.
Heat-related dangers will be on the rise over the weekend for much of the Northwest as scorching heat settles in.
As the Northeast continues to clean up from destructive storms early this week, more rounds of severe weather and flash flooding loom for early next week.
Parts of the South will get major relief from heat, humidity and storms next week while other locations will be at greater risk for flash flooding.
Yellowstone National Park's Firehole Lake Drive was closed Thursday, July 10, as portions of the roadway's asphalt melted amid the summer's recent heat wave in the Northwest.
Pinellas Co., FL (1992)
A tornado blew a catamaran into a car, injuring six people.
Eastern North Carolina (1842)
Hurricane struck, "the worst in 80 years"; vessels ashore on beaches; village of Portsmouth washed away.
Basin, WY (1900)
114 degrees -- hottest ever for Wyoming.