At least 30 people have died throughout the southern United States after severe storms and tornadoes ravaged entire communities and left half a million Americans without power amid the global coronavirus pandemic, according to reports.

At least eleven people died in Mississippi, and six more were killed in northwest Georgia. Two other bodies were pulled from damaged homes in Arkansas and South Carolina.

Governors in Alabama, Louisiana and Mississippi meanwhile declared states of emergency as residents grappled with stay-at-home orders caused by the pandemic, while also requiring emergency assistance for their damaged homes.

The storms caused extensive flooding and mudslides overnight in mountainous areas, knocking out electricity for about 750,000 customers in a 10-state swath ranging from Texas to Georgia up to West Virginia, according to Poweroutages.us., which tracks real-time data on power outrages across the country.

In Alabama, where Governor Kay Ivey suspended social distancing rules related to the coronavirus pandemic because of the weather threat, people wearing protective masks huddled closely together in a storm shelter.

A suspected twister lifted a house, mostly intact, and deposited it in the middle of a road in central Georgia. In Louisiana, winds ripped apart a metal plane hangar.

The National Weather Service tallied hundreds of reports of trees down across the region, including many that punctured roofs and downed power lines. Meteorologists warned the mid-Atlantic states to prepare for potential tornadoes, wind and hail on Monday as storms continued to batter down parts of the country.

In Georgia, Murray County Fire Chief Dewayne Bain told WAGA-TV that two mobile home parks were severely damaged, with five people killed and five others hospitalised after a line of narrow line of storms left a five mile long path of destruction. Another person was killed when a tree fell on a home in Cartersville, the station reported.

Mississippi's death toll rose to 11 early Monday, the state's emergency management agency tweeted, promising details later in the morning.

Storm Dennis in pictures Show all 40 1 /40 Storm Dennis in pictures Storm Dennis in pictures Flood water surrounds Upton upon Severn in Worcestershire. Severe flood warnings remain in place in the wake of Storm Dennis, with more rain expected to fall in the week PA Storm Dennis in pictures A husky and its owner are rescued by emergency services after flooding in Nantgarw, Wales after Storm Dennis hit the UK PA Storm Dennis in pictures Waves crash against the harbour wall in Isle of Whithorn Getty Storm Dennis in pictures An employee cleans a nail salon on Market street in Pontypridd after Storm Dennis hits the UK leading to widespread flooding PA Storm Dennis in pictures Flooding from the River Wye Getty Storm Dennis in pictures Laura Court and Louise Bedgood mop up the floor of Lougos hair dressers in Oxford Street, Nantgarw EPA Storm Dennis in pictures A Land Rover wades through flooded roads in the Wye Valley, near the hamlet of Wellesley in Hereford Getty Storm Dennis in pictures A rainbow appears over flooded fields in the Wye Valley Getty Storm Dennis in pictures A firefighter carries a dog to safety as part of ongoing rescue operations due to flooding in Nantgarw PA Storm Dennis in pictures Two men cleaning up the street in Pontypridd PA Storm Dennis in pictures Rescue operations continue after flooding in Nantgarw PA Storm Dennis in pictures Flood water surrounds Upton upon Severn PA Storm Dennis in pictures Members of the public start the clean up following flooding from storm Dennis in Newcastleton, Scotland Getty Images Storm Dennis in pictures Local residents remain cheerful as walk through receding floodwater in Mountain Ash, Wales PA Storm Dennis in pictures A car trapped by debris carried by floodwater, on the road outside the Aberdare Hotel in Mountain Ash, Wales PA Storm Dennis in pictures Flood water surrounds Upton upon Severn PA Storm Dennis in pictures Flood water surrounds abandoned cars left in a flooded street in Tenbury Wells, after the River Teme burst its banks in western England AFP via Getty Storm Dennis in pictures A man rescues a floating plant pot from flood water, outside of a flood-bound house in Tenbury Wells AFP via Getty Storm Dennis in pictures Items float in flood water inside a flooded charity shop in Tenbury Wells AFP via Getty Storm Dennis in pictures Flood damage in Bridge Street, Crickhowell, South Wales Reuters Storm Dennis in pictures A digger is used to clear debris, carried by floodwater, from the road outside the Aberdare Hotel PA Storm Dennis in pictures Flood water surrounds abandoned cars left in a flooded street in Tenbury Wells AFP via Getty Storm Dennis in pictures An Environmental Agency Officer gives a briefing as the River Ouse in York continues to rise potentially causing further flooding as Storm Dennis causes disruption across the country Getty Storm Dennis in pictures A man walks through a flooded convenience store in Tenbury Wells AFP via Getty Storm Dennis in pictures Flood water surrounds abandoned cars left in a flooded street in Tenbury Wells AFP via Getty Storm Dennis in pictures Employees of York City Council use sand bags to increase flood defences Getty Storm Dennis in pictures A van is driven through standing water on a road in Tenbury Wells AFP via Getty Storm Dennis in pictures A footbridge in Pontypridd is blocked by debris after Storm Dennis hit the UK PA Storm Dennis in pictures Waves crash over the lighthouse at Porthcawl, South Wales Reuters Storm Dennis in pictures Members of the 4th Battalion Royal Regiment of Scotland erect flood barricades in Ilkley, West Yorkshire AFP via Getty Storm Dennis in pictures Bricks and debris cover damaged cars after part of a building collapsed in Herne Bay AFP via Getty Images Storm Dennis in pictures An empty coach sits abandoned in flood water after the River Teme burst its banks near Lindridge AFP via Getty Images Storm Dennis in pictures Standing water on a road in Tenbury Wells AFP via Getty Storm Dennis in pictures A firefighter carries a dog to safety as part of ongoing rescue operations due to flooding in Nantgarw PA Storm Dennis in pictures A rescue boat is lifted from the water by Mountain Rescue crews after a river patrol on the River Ouse in York Getty Images Storm Dennis in pictures Flood water surrounds grave stones in a graveyard in Tenbury Wells AFP via Getty Images Storm Dennis in pictures One-year-old Blake is carried by a rescue worker as emergency services continue to take families to safety PA Storm Dennis in pictures A dog and its owner are rescued by emergency services after flooding in Nantgarw PA Storm Dennis in pictures A car passes over Teston Bridge near Maidstone in Kent PA Storm Dennis in pictures An aerial view of the Welsh village of Crickhowell which has been cut off Getty Images

Several apparent tornadoes spun up in South Carolina, where dozens of homes appeared damaged in a line from Seneca to Clemson. Emergency officials were working to open shelters in the North Carolina mountains, where up to 5 inches (13 centimetres) of rain fell in a few hours.

In Chattanooga, Tennessee, at least 150 homes and commercial buildings were damaged and more than a dozen people treated, but none of their injuries appeared to be life-threatening, Chattanooga Fire Chief Phil Hyman said Monday morning.

"It's widespread damage that happened extremely fast, " he said. "I advise people to stay in their homes at this point. As far as safety is concerned, we still have active power lines that are down."

Mississippi Governor Tate Reeves declared a state of emergency on Sunday night after he said several tornadoes had struck the state.

Bill Gates warns that a viral outbreak similar to coronavirus could happen every 20 years

"This is not how anyone wants to celebrate Easter," Mr Reeves said on Twitter. "As we reflect on the death and resurrection on this Easter Sunday, we have faith that we will all rise together."

Strong winds late Sunday toppled power lines and blew trees onto several houses in Clarksdale, Mississippi, trapping some people inside, Mayor Chuck Espy said.

"I know these are some tough times and I'm just asking everyone to stay prayed up", Mr Espy said.