(CBS News) SILVER SPRING, Md. - Another round of powerful storms rolled through the Mid-Atlantic region overnight, ending a weekend of extreme weather that's being blamed for at least 17 deaths and that left more than two million customers in the eastern U.S. without power.
Even where it wasn't raining, there was record-breaking heat in many places over the weekend. Nashville, Tenn. and Columbia, S.C. both hit all-time high temperatures of 109 degrees.
Nearly 30 cities recorded 100 degrees or higher Sunday.
Punishing heat and no electricity to run air conditioners or anything make a dangerous combination.
Areas from Indiana to Virginia got the worst of the weekend weather.
A violent storm system formed around Chicago Friday and moved east, packing winds up to 90 miles an hour.
Three days later, there are still widespread outages in Virginia, Maryland, Washington, D.C., Ohio, Indiana, West Virginia and New Jersey.
Officials of power companies say some areas may be without electricity for several more days.
Federal offices in Washington will be open today, but non-essential workers will be allowed to stay home.
And Maryland Gov. Martin O'Malley is giving state workers the option of staying home.
Throughout the D.C. area, hundreds of thousands of people were facing a third day of sweltering heat with no electricity Monday.
"We are out of power absolutely, and out of air conditioning, especially," says Gary Heinze.
He charged his computer and cell phone at a sports bar in Fairfax, Va. Sunday. It could be days before his power is fully restored, but he's more worried about his neighbor's son.
"He has bad asthma and he has a respirator sort of thing that he has to use at night, and they're running off a generator now, but who knows how long that will last?" Heinze says.
Across the region, residents did whatever they could to deal with the inconvenience, cramming malls, stocking up on ice and, in some spots, waiting in long lines for gas.
"We went to one gas station. We thought, 'Oh, this is great.' But there wasn't any power," one woman noted.
A violent weather system sparked the outage Friday night. The storm swept in without warning and, in just 10 hours, traveled about 600 miles, packing hurricane force winds.
"The truth is, when a catastrophic event like this hits and when you have 70 mph winds and heavy rains, there are going to be outages," Pepco Region President Thomas Graham observed.
He says his utility crews are working around the clock to restore service to the D.C. and Maryland area, starting with critical facilities such as hospitals and nursing homes.
But that isn't stopping O'Malley, Maryland's governor, from keeping up the pressure.
"Nobody will have their boot further up Pepco's backside then Ii will to make sure that we get there," he vowed to reporters.
To that, Graham remarked, "Does it make me work harder or does it make my company work harder? We're already working hard."
Graham says power crews from as far away as Oklahoma and Canada are chipping in.
Pepco says it's working to make service more reliable in the future, especially during storms.
Over the next five years, the company plans to invest more than $910 million on infrastructure improvements - a big part of that will be tree-trimming.