The sharp leading edge of a derecho means weather can transform from peaceful to perilous in seconds.
ONLINE BONUS IMAGE: Immense damage was caused by falling trees, as at this house on Cleveland Avenue.
Jeanne Nicholson Siler
It seemed to come out of nowhere on Friday, June 29– a storm that would devastate the state, leaving millions without power for days and six people dead– two in Albemarle County. Now, we know what it's called: a derecho.
Aptly named for the Spanish word meaning "straight," a derecho is a windstorm blowing from the front of a rapidly-advancing– and very straight– storm line. Photos of such storms– pronounced deh-REY-cho– show the crisp edge of such fronts, and on the ground, that straight storm line means instantly changing weather conditions.
"In this case, it started off in Illinois in the afternoon and rolled through Virginia during the nighttime hours," says Sterling-based meteorologist Brian Lasorsa with the National Weather Service, noting that such fronts move rapidly, with this one advancing at an average speed of 75mph. He says the fierce winds are fueled by the combination of heat and humidity and that when rain cools that air it creates a series of microbursts– large areas of wind crashing down– like the ones that wreaked havoc on Charlottesville in 2010.
Fortunately, Lasorsa says, derechos are relatively rare, with Virginia's last widespread derecho occurring in 2008.
Across the state, residents were taken by surprise Friday night by the sudden wall of winds often topping 60 mph but bringing little rain. The damage was tremendous, as 10 main power transmission lines across the state came down.
In Charlottesville, 10,610 of 23,688 Dominion Virginia Power customers lost power while Albemarle was even harder hit with 28,494 out of 40,571 losing power. That's 70 percent of county customers, and some Ivy and Crozet residents have been told it could be Saturday the 7th of July– eight days after the outage– before their power gets restored.
In addition to destroying property, falling trees killed two in Albemarle. John Porter, 64, of Decca Lane, died after he stepped on his deck and was crushed by a falling tree. Fifty-two-year-old Catherine Ford, was also killed by a falling tree when she got out of her car seeking phone service on Scottsville Road. Despite efforts by witnesses to assist Ford, she was pronounced dead at the scene.
As this paper goes to press on Tuesday, July 3, four days after the storm hit, more than 9,000 Dominion customers in Albemarle remained powerless, while in Charlottesville, 649 customers were still in the dark, as food spoiled and daytime temperatures remained near triple digits. The Department of Health warns that any perishable food that rises above 41 degrees for four hours should be discarded.
The town of Crozet canceled its 4th of July celebration due to damage to Claudius Park. There are several cooling centers open, and UVA offered its fitness center showers to the public.
With temperatures and humidity expected to remain high in coming days, the potential for more storms exists, but the National Weather Service's Lasorsa says any new storms are unlikely to match the magnitude of the derecho.
"We don't expect it to be as widespread," he says, "more like typical thunderstorms, but they could still contain gusty winds."
Let's hope not too gusty.