It could be several more days before electricity is restored to areas hit by vicious storms that killed at least 13 people and left 3 million power customers to negotiate sweltering temperatures without air conditioning.
Massive storms sweeping across the Eastern U.S caused the deaths of two young cousins camping with their families in New Jersey after a tree fell on their tent.
Across a swath from Indiana to New Jersey and south to Virginia, officials warned the heat wave could take a toll on the elderly, young or sick.
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A child looks at a house struck by a tree after a violent thunderstorm ripped through the area on Saturday evening, in Falls Church, Virginia
Severe weather warning: The orange shading shows the areas on Heat Alert
Problems from the storms during the triple digit heat wave ranged from a damaged prison in Illinois to tree-strewn train tracks that stranded 232 Amtrak passengers for more than 20 hours in West Virginia.
The storm that whipped through the region Friday night was called a derecho (duh-RAY'-choh) , a straight line wind system that sweeps over a large area at high speed.
The storm, which packed wind gusts of up to 90 mph, began in the Midwest, passed over the Appalachian Mountains and then drew new strength from a high pressure system as it hit the southeastern U.S., said Bryan Jackson, a meteorologist with the National Weather Service.
Emergencies have been declared in Maryland, West Virginia, Ohio, the District of Columbia and Virginia, where Gov. Bob McDonnell said the state had its largest non-hurricane outage in history, as more storms threatened. 'This is a very dangerous situation,' the governor said.
Power officials said the outages wouldn't be repaired for several days to a week.
Sweltering: The hot weather is set to continue into next week forcing the three million without power to seek refuge in public places with air conditioning
Lighting flashes Saturday morning, June, 30, 2012 in Hebron Maryland
A downed tree takes out two vehicles in Upper Deerfield, New Jersey on Saturday as violent storms swept across the eastern U.S
Mike Wolfe's pickup truck lies under a fallen tree in front of his house after a severe storm in Falls Church, Virginia. Visible is a tongue-in-cheek 'for sale' sign
The storm did damage from Indiana to New Jersey, although the bulk of it was in West Virginia, Washington and the capital's Virginia and Maryland suburbs.