Monster storm sweeps toward East Coast with 120 million Americans in its path as flash floods swallow homes and force immediate evacuations

Flash flood warnings have already been issued as millions prepare for a giant storm sweeping across 23 states starting today.

Heavy downpours are expected to move through the Southeast Thursday morning, triggering alerts for life-threatening floods along the Georgia-Tennessee border, where several inches of rain led to local evacuations overnight.

The National Weather Service warned: ‘This is a particularly dangerous situation. Seek higher ground now! Life threatening flash flooding of low water crossings, small creeks and streams, urban areas, highways, streets and underpasses.’

Homes in Fannin County, Georgia and Polk County, Tennessee were seen being overrun by overflowing waterways as over six inches of rain fell early Thursday morning. 

That massive low-pressure system will quickly sweep into the Mid-Atlantic and Northeast throughout the day on Thursday, generating thunderstorms in the Carolinas and steady rain showers from Virginia to Maine.

Approximately 120 million Americans are in the path of the storm, and AccuWeather meteorologists warn that severe downpours along the East Coast will likely cause travel disruptions and dangerous flooding in multiple coastal cities through Saturday.

That includes parts of eastern Virginia, most of Delaware, southern New Jersey, the New York City metropolitan area, Connecticut, Rhode Island and Boston, Massachusetts.

AccuWeather meteorologist Tyler Roys warned in a statement: ‘It doesn’t take a torrential downpour to create dangerous driving conditions. Even relatively light rain can make roads surprisingly slick after weeks of dry weather.’

Forecasters believe the storm will stall once it reaches the East Coast as winds higher up in the atmosphere slow down and stop pushing it across the US.

Another smaller weather disturbance known as a shortwave is also expected to move through and help reinforce the rainstorm, causing the system to linger instead of racing away.

This will keep the heaviest rain focused in a relatively narrow band for days along most of the East Coast, drenching millions in cities such as New York, Boston, Atlantic City, Hartford and Norfolk.

AccuWeather Senior Meteorologist Brett Anderson said in a statement: ‘This is the type of setup that can quickly lead to flash flooding as heavier rain cells may continuously move over the same areas.’

Drivers in Georgia and Tennessee were already told to stay off the roads unless they are evacuating a flooded area. 

AccuWeather senior meteorologist Alex Sosnowski explained that the extremely dry conditions along the East Coast over the last three weeks will make roadways even more dangerous as the downpours arrive.

The rain will mix with a thick buildup of oil and dust on the pavement to form a slippery combination that tires have trouble gripping to. Drivers have been urged to drive slower than normal and stay off any roads covered in water. 

‘Turn around, don`t drown when encountering flooded roads. Most flood deaths occur in vehicles,’ NWS added in a statement.

As the storm barrels into the Northeast, forecasters revealed that the first impacts of the polar vortex collapse will hit the US by Friday night.

Temperatures during the rain blast are expected to plummet into the 40s and 50s, with wet snow possible in higher elevations in Maine, New Hampshire, Vermont, New York, Michigan, Ohio and Pennsylvania.

The polar vortex is a powerful band of winds swirling high above the North Pole, helping to keep extremely cold air trapped over the Arctic Circle.

During major disruptions, like the one currently taking place, those winds weaken or even reverse direction, sending temperatures in the upper atmosphere soaring.

These changes can destabilize the normally tight jet stream over the Arctic, causing the vortex the tilt and plunge south, bringing bitter cold to parts of Canada and the northern US.