Heavy, sustained winds across Tennessee likely a derecho, NWS said

Mariah Timms
The Tennessean

Middle Tennessee was likely touched by a rare weather event on Friday evening: a derecho. 

If the name is unfamiliar, it is because only a few of the storms occur nationwide each year, according to Dan Hawblitzel, a meteorologist with Nashville's National Weather Service team. 

"The Midwest is where these storms most often occur," Hawblitzel said. 

What is a derecho?

A derecho is specific type of weather event that includes strong winds and a line of rapidly moving thunderstorms.  Derechos also include wind gusts of at least 58 mph sustained through the storm, and higher gusts of 75 mph wind. 

The storm Friday included those elements through parts of southern Illinois, Kentucky and northern Tennessee, Hawblitzel said.

Did Tennessee get hit by a derecho?

"So far it does appear to get close to that when it picked up steam and moved across our area," Hawblitzel said. "We have measured reports across that path."

The storm originated in Nebraska, but the strength waned over much of Missouri, before regenerating over St. Louis as the front moved eastward. 

The NWS said that although a derecho can produce destruction to a similar degree as tornadoes, the damage typically occurs along a relatively straight swath.

As a result, the term "straight-line wind damage" sometimes is used to describe derecho damage.

More storms incoming, but another derecho unlikely

Damage and a downed tree are seen after severe storms Friday night near Glenrose Avenue and Thompson Lane in Nashville.

Reports of trees down, tangled power lines and outages were widespread on Friday evening after the severe storm front moved through. 

More storms are forecast for midmorning Saturday, Hawblitzel said, but will be less severe — as long as they stay early.

"If they move in earlier, they're less likely to be strong," he said, because the later in the day the front comes through, the more time the atmosphere will have had to build up energy. 

As of 11 p.m. Friday, the best guess for the storm's arrival was 9 or 10 a.m., which was a good sign. 

Reach reporter Mariah Timms at mtimms@tennessean.com or 615-259-8344 and on Twitter @MariahTimms