Hundreds of thousands are still without power and air conditioning from the Midwest to the mid-Atlantic, following a dangerous derecho last Friday. An unforgiving heat wave is making those without power struggle to stay cool.
"A derecho is defined as a widespread and long-lived wind storm that accompanies rapidly moving showers or thunderstorms," AccuWeather Meteorologist Kristina Pydynowski said.
Friday's violent thunderstorms that slammed a 700-mile-long corridor from Indiana to the southern mid-Atlantic coast resulted in extensive straight-line wind damage and millions of power outages. Winds of 90 mph and locally higher were recorded along the path of the storms.
The winds of the derecho were not only strong enough to cause localized damage by downing trees onto power lines, but they were ferocious enough to damage entire power grids.
"The damage was worst than the last hurricane that hit us," Marcus Beal, a senior project manager of Pepco, said. Pepco is a power company that serves Montgomery and Prince George's counties in Maryland and Washington, D.C.
Beal explained that there were more power outages and more damage from Friday's storms than from Hurricane Irene.
"Unlike a hurricane when you have plenty of warning time, there was less warning with these storms," Beal added.
West Virginia and Ohio were hit very hard by the damaging storms resulting in numerous power outages. American Electric Power reports that 45 percent of their Ohio customers were without power during the height of the outages.
"West Virginia was certainly hardest hit. The grid was severely impacted," Tom Kearney, area manager of West Penn Power, said. "The high winds crumpled metal transmissions, which are very well engineered and well built."
AccuWeather Meteorologist Henry Margusity put the damage caused by the derecho in perspective by explaining that it was worse than damage caused by some ice storms. During ice storms, individual lines are snapped by the weight of ice that accumulates or by downed tree branches toppling onto lines. With wind storms like derechos, entire full-grown trees can be uprooted, falling onto homes, roadways or transmission lines.
Difficulties Restoring Power
The first and foremost concern of power companies is to restore downed live wires. People are urged never to touch or move a wire to avoid electrocution. Remember, there is no way to tell just by looking at a line if there is still energy running through it or not.
Damage and downed trees make it extremely difficult and time-consuming to restore power when it comes to wind storms.
Furthermore, high voltage transmission lines are often very remote. Repairing the transmission lines is also challenging. According to Kearney, helicopters must be used to fix transmission lines.
West Penn Power and Pepco are both hoping to restore power to most, if not all, customers by the end of the week. Crews will work straight through July Fourth to get electricity up and running for their customers.
The midwestern United States will be in the crosshairs of potent thunderstorms into Saturday night.
Much of the eastern United States will continue to swelter with above-average temperatures into the end of the month.
Conditions will deteriorate across Hawaii this weekend as Darby delivers locally heavy rain and rough surf. But the tropical storm will provide long-term benefits.
Those looking for a break from the heat across the central United States will be in luck as a slow cooldown is in store starting this weekend.
Lightning killed a teenager on Friday, the second teen lightning death in three days. With thunderstorms continuing to rattle several parts of the nation, more lives will be at risk.
The more than 100,000 people expected to attend the annual Glorious Goodwood festival next week will want to keep a brolly handy.
New Zealand (1995)
Extreme cold - a bay in Littleton Harbor froze for the first time in "living memory".
Simla, CO (1996)
4.5" diameter hail.
Mid-Atlantic Ocean (1788)
(22nd-24th) George Washington Hurricane; After causing ship disasters off SW Bermuda, the storm moved NW over Tidewater, NC and VA to pass right over George Washington's Mt. Vernon plantation. On July 24th, George Washington wrote in his diary: "About noon the wind suddenly shifted from NE to SW and blew the remaining part of the day violently from that quarter. The tide this time rose near higher than it was ever known to do, driving boats, etc. into fields, where no tide had ever been heard of before, and most, it is apprehended, having done infinite damage on their wharves at Alexandria, Norfolk, Baltimore, etc. At home all day."