You Don't Have To Be Hit By A Tornado To Receive Tornado Damage

Schematic of a tornado-producing thunderstorm from NOAA.
Click on the link to make it bigger and easier to see.
The blue down arrow behind (just to the left of the tornado
in the image) can cause as much damage as the actual tornado.

There was proof Friday, as if any experts needed any, that a tornado doesn't have to actually directly hit something to cause tornado damage.

In a remote part of western Texas near the town of Orla, halfway between El Paso and Midland-Odessa, a tornado, apparently a strong one, touched down on Friday. It pretty much went over remote scrubland, so it didn't cause much direct damage.

However, a nearby RV park had some serious damage, and one person was injured.  The tornado did not hit the RV park. The culprit? Something called a rear-flank downdraft. 

A rear-flank downdraft is an area of often very strong winds near and mostly to the back side of a tornado or rotating wall cloud, which is often called a mesocyclone.  (The wall cloud or mesocyclone is often but not always a precursor to a tornado).

It's created by a strong downdraft behind the mesocyclone that hits the ground, with great force, spreading out and causing strong straight-line winds.

That's why if you receive a tornado warning but the tornado itself seems to be heading to a point near, but not over your house, take your tornado safety precautions anyway.

For one thing, the tornado could unpredictably change course and run you over.  Or the tornado could miss, but you'd still be in the rear flank downdraft.

In the case of the Orla, Texas rear flank downdraft, the wind hit speeds of 100-130 mph, equivalent to an EF-2 tornado, notes the the National Weather Service in Midland-Odessa, Texas.  That's why thre was so much damage there.

The video below shows a very close miss by the big tornado in Tuscaloosa, Alabama in 2011.

You'll see the tornado pass by basically across the parking lot from the videographer at about 1:10 to 1:22 into the video. The very strong left to right winds immediately following the tornado starting at about 1:22 or so is the rear flank downdraft. As you can see, the winds in the downdraft seem at least as strong as at the edge of the tornado itself.

The rear flank downdraft winds wane a little, but still continue very strong for at least another two minutes after the tornado.

Watch: