Remembering the Derecho of 2012
HARRISONBURG, Va. (WHSV) -
June 29 marks 8 years since the 2012 derecho that left a quarter of a million people without power here in the Shenandoah Valley.
Homes and businesses were damaged, trees and power lines were knocked down, and millions from the Midwest to the East Coast were left dealing with record-setting heat in the aftermath of powerful winds.
The damage looked fairly similar to that of a tornado.
The National Weather Service defines a derecho as, ”a widespread and usually fast-moving windstorm associated with convection. Derechos include any family of downburst clusters produced by an extratropical MCS, and can produce damaging straight-line winds over areas hundreds of miles long and more than 100 miles across.”
Simply, it’s a large complex of storms that is typically fast moving, and leads to severe wind damage across hundreds of miles. A derecho is not just any severe storm. A storm is classified as a derecho if it travels at least 240 miles (the 2012 derecho traveled 700 miles). A derecho will also produce nearly continuous or widespread severe wind damage. Winds can often exceed 60-100mph!
Highs on the day of June 29, 2012. Temperatures has been heating up through the week. Highs on the day of the derecho reached near or more than 100° across the area.
|Downtown Harrisonburg||Charlottesville||Winchester||Moorefield, WV||Petersburg, WV||Luray||Waynesboro||Upper Tract, WV||Woodstock|
|105°||104 °||103 °||102 °||100 °||100 °||100 °||99 °||99 °|
If you look at the archive radar image from that evening, even though the storms didn’t start to move across the Allegheny mountains until after about 8 p.m., the severe winds raced out ahead of the storm. That’s one thing that can make radar images look deceiving. You’re only looking at the rain intensity, but often in strong and severe storms the high winds will race out before the rain starts. What made these storms so bad, was the wind didn’t last several minutes as in a typical storm. Strong winds lasted 30-60 minutes.
Here are the peak wind gusts from some weather stations across the area:
|Roanoke||Elkins, WV||Afton Mtn||Winchester||Weyers Cave (SHD)||Big Meadows (SNP)||Woodstock||Charlottesville||Upper Tract, WV|
|81 mph||64 mph||64 mph||61 mph||60 mph||59 mph||55 mph||54 mph||52 mph|
In the Shenandoah Valley, more than a quarter million people lost power and had to survive the blistering hot temperatures for days. Highs remained in the 90s for the 10 days following the storm.
Energy companies worked hard in the heat to restore power, and have since made improvements to help prevent as many outages as they can if such a storm were to hit again. They have better communication with their customers to help pinpoint outages, and have moved conductors underground in the most outage-prone areas
Dominion Energy describes the derecho of 2012 the third worst storm to hit Virginia after it knocked out power to one million people.
While you may not have heard of a derecho before June 29, 2012- it’s not a new type of storm and yes it has happened in the past, and has happened since 2012.
In mid June, 2013, there was another derecho that affected our area. Multiple trees came down through the entire region. Here’s a look at the progression of radar from the 2013 event.
Most recently, in May of 2018 there was another derecho event and this was more of what Meteorologists consider a low-end derecho event. It still led to numerous wind damage reports from southern Ohio, through West Virginia and Virginia.
Remember, even though in Meteorological terms we called this one a “low-end” derecho overall, a damaging storm is a damaging storm. If you had damage from this event, you probably didn’t think it was very “low-end.” Here’s a tweet on the satellite from the May, 2018 event.
Not all lines or clusters of storms are derechos. Often we can’t classify them as a derecho until after an event. What’s important is to pay attention to all severe thunderstorm warnings. On June 29, 2012, a severe thunderstorm warning was issued just like any other time a thunderstorm becomes severe. (Severe wind is wind gusts 58mph or greater).
Not every derecho event is similar. If you compare the three that were mentioned in this article by the wind damage reports, you can clearly see how the June 2012 event was an extreme event.
Remember that it doesn’t take a derecho or a tornado to cause severe wind damage, though. Always take severe thunderstorms seriously and stay weather aware when you plan outdoor activities.
If you have any saved photos or video of the derecho or damage, you can submit them through the link below:
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