Deadly summer storms rain down on US: Twenty-one dead in the South as NYC is put on 'red alert'

Texas, Arkansas, Kentucky, Missouri and Tennessee were all hit over the weekend by a bevy of twisters, heavy winds and flooding.

The storms, so far, have killed at least 21 people, after tornadoes and severe weather struck the central and southern United States.

Among them were four children, spurring a statewide emergency declaration in Kentucky, as the mass of severe weather is set to move east Monday.

More than 100million across the East Coast are thus at risk, including the Tristate - where thunderstorms and possibly even a tornado are in the forecast.

Seven are already dead in northern Texas, eight in Arkansas, two in Oklahoma and four in Kentucky - with a fifth person 'fighting for their life,' the Blue Grass State's governor revealed in a press conference called Monday.

'Sadly we can confirm that we have lost at least four Kentuckians from last night's storm,' Gov. Andy Beshear said at the emergency conference from the Kentucky Emergency Operations Center.

'That means we know that there are at least four families this morning that have suffered the loss of a loved one less than 24 hours ago that are hurting 

'We ought to rally around them and do everything we can to carry them and the days the weeks and the years to come,' he added - before revealing the uncertain fate for the fifth person is 'fighting for their life.'

The four fatalities, he said included a 67-year-old woman in Mercer County, a 62-year-old woman in Hardin County, a 48-year-old woman in Hopkins County, and a 34-year-old man in Jefferson County - all of whom went unnamed.

The update brought the nationwide death toll over the Memorial Day Weekend up to 21, after a woman and two of her children saw their home struck by a tornado Saturday night in Valley View, Texas, killing all three.

'It was a really terrible thing,' Benito Esparza, the sole survivor's brother, told CNN in Spanish Monday, of the fate of sister-in-law Laura Esparza and her children Marco, 10, and Miranda, 16. 

His brother, Refugio Esparza, survived the tornado, but suffered a broken leg and pelvis. 

'He lost three people, his wife and two kids,' Benito Esparza said. 'It's not easy.'

He added how two of Refugio's older children were not at the home at the time of the tornado, which first surfaced outside the Dallas-Fort Worth area overnight Saturday, and saw at least seven were killed. 

That made it the deadliest tornado in state history since 2015 - leaving residents to dig through the tons of rubble and debris left behind.

That distinction was not lost on Benito, who spent Monday morning sifting through the remains of his brother's home for what was left.

'It's a very big disaster for everyone, as you can see,' said Esparza of storm's ongoing effect, as recovery efforts to continue.

He further recalled how his three family members  died after their trailer was thrust across a street - a scene that was sadly not unique across the country Saturday and Sunday.

There were more than 20 tornado reports within that span ranging from Texas to Missouri, bolstered by several detailing the damage left behind and, of course, the casualties.

Elsewhere in Texas, violent storms overtook 18-wheelers, destroyed homes, and brought down power lines - even crushing a Shell station in Cooke County.

This left 125 people trapped for a period Saturday night, officials said - revealing how all miraculously were retrieved uninjured.

There, the storms inflicted some of their worst damage  - in a region spanning from north of Dallas to the northwest corner of Arkansas.

 The system then threatened to bring more violent weather to parts of the Midwest, affecting counties in Arkansas, Oklahoma, and Kentucky.

A slew of deaths in those states were recorded Sunday, mostly from falling trees.

One such death was confirmed in Mercer County early Monday, before the governor confirmed four overall had died.

That person was pronounced dead along with another in Louisville, where Mayor Craig Greenburg confirmed it was a storm-related death. 

Hours later, the state's governor revealed the tally was up to four - a number that very well could still rise, he said.

The trees and homes damaged in those states were hit not only by tornados, but by winds that reached 135mph in some places, leaving some 500,000 without electricity across Arkansas, Oklahoma, Kentucky, and Texas.

Out of the 21 who died, seven of the storm-related deaths came from Cooke County, Texas, as well as eight across a range of areas in Arkansas.

Another two were recorded in Oklahoma's Mayes County, where trees have been uprooted by twisters all over town, with powerlines down and structures flattened.

In Arkansas, The National Weather Service in Tulsa said a survey team found EF-3 damage near the town of Decatur, where at least one tornado hit.

Another two hit Beaver Lake and others in Benton County, where three of the eight casualties were recorded. 

A 26-year-old woman, moreover, was found dead outside a destroyed home in Olvey, as recovery efforts in all four states continue.

In addition to the incident described by Esparza, the dead in Texas included two other children, ages 2 and 5, and three other family members also found together in a tornado-struck home in Cooke County.  

The severe weather, meanwhile, is not over, after it pushed east into the Midwest and the Ohio Valley over the course of Sunday.

Missouri was the state hit hardest Sunday, where residents of Mehlville reported a violent storm and possible tornado that destroyed dozens of houses.

This saw cities like Chicago, Indianapolis, Nashville, Tennessee, St. Louis, and Cincinnati hit by strong showers and damaging winds, but no tornados, as of writing.

It is set to finish off today over the East Coast, where risk of severe weather was issued to mid-Atlantic strongholds such as Baltimore; Washington, D.C.; and Charlotte and Raleigh, North Carolina.

There, 27 million people are at risk of strong to severe thunderstorms, with ore than 110 million people are at risk of severe weather in general.

That includes south of New England, where there is a level 2 out of 5 threat. 

Meanwhile, Philadelphia, Baltimore and Washington, DC, are at risk for tornadoes, but the chances for any to develop are low, officials said.

The travel hubs of Atlanta, New York, and Philadelphia will also have to contend with the prospect of damaging storms, and even the odd tornado.

This will likely lead to delayed or canceled flights Monday, as Memorial Day winds to a close.

Travelers are urged to check the current weather conditions of the states they are heading to. 

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