5 years later: A look back at the 2012 Derecho

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ROANOKE, VA Hours after the historic wind storm moved through on June 29, 2012, the term "Derecho" (pronounced "deh-RAY-cho"), became a household name.

It has been five years since the rare wind storm barreled into the region, after a day of record, triple-digit heat.

THE DAY OF THE EVENT
The region had seen several days of extremely hot temperatures. The morning of June 29th, the overnight low was 84º, and had we not cooled down after the wind storm moved through, it would have been record-setting.

The afternoon high of 104º did set a record, a tie for the hottest June temperature on record, and the warmest June day in over two decades.

The extreme heat helped provide the fuel for the storm complex that started near Chicago early in the evening, then expanded and got stronger, moving through southwest and Central Virginia between 8 p.m. and 9:30 p.m. that evening.

The mountains did manage to weaken the storms some, but not enough to keep it from producing an 88 mph wind gust in White Sulphur Springs, West Virginia. As the storms moved east of the Highlands, Roanoke recorded a wind gust of 81 mph at the airport.

The storm complex continued eastward, gradually getting weaker before exiting the eastern seaboard.

POWER OUTAGES
More than 4 million customers lost power due to the multi-state wind event. This was the largest non-hurricane outage on record, which left many customers without electricity for a week or more. Not to mention, the outage came during a time when the region was experiencing some of the hottest weather since the early 1900s.

DEATHS
More than a dozen died as a result of the wind event itself, mostly from trees falling onto homes or vehicles. Another 34 died from heat-related illnesses due to the lack of electricity in the days that followed.

THE FORECAST
Unlike many major tornado outbreaks in the recent past, this particular event was not forecast well in advance. Warm-season derechos, in particular, are often difficult to forecast and frequently result from subtle, small-scale events that are difficult to predict less than 12 hours in advance.

With better data and model improvements, more recent wind events have been better predicted with up to 18 to 24 hours notice.

According to a National Weather Service assessment of the Derecho, overall, lead times (advanced warning) were greater than 30 minutes and all deaths occurred within severe thunderstorm warning polygon boundaries.

The bigger issue was getting those warnings out to those in the path.

WDBJ COVERAGE AND NEW WAYS TO WARN
Several hours before the Derecho struck, meteorologist Brent Watts was on-air with cut-ins, giving a "heads-up" that the storms may approach later in the evening. As the line of storms reached central West Virginia, continuous coverage on TV resumed until the event cleared the entire region.

Social media was another way to reach those in the path, but due to the algorithms used by Facebook, not everyone received the warnings.

After the Derecho, WDBJ7 invested in cutting edge technology for its weather app. The technology uses geo-fencing, or targets specific hometowns. This allows the meteorologist to send out area-specific alerts and custom videos to warn of approaching weather events using the WDBJ7 Weather App.

"We are currently the only local station to utilize this technology," explains Chief Meteorologist Brent Watts. The technology developed by The Weather Company and IBM, was used extensively during the recent tornado outbreaks and flooding events. "We are committed to using every piece of technology possible to keep our viewers informed of dangerous weather, and ultimately keep them safe."