What Caused This?

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I went to a Rotary Club mixer recently and was asked about this photograph by Mike Hutmacher of the Wichita Eagle. "How could that one house have been destroyed?!"

The two most likely explanations are that the house had a construction flaw that was not present in the surrounding homes. Or, a "suction vortex" struck the house or both. Here is an explanation of the phenomena.

Many larger tornadoes have multiple, smaller vortices (originally called a "suction vortex" by their discoverer, Dr. Ted Fujita) that rotate around the main funnel. The winds are stronger in those smaller vortices than in the main tornado.

Looking at the tree slightly left of center in the lower foreground, it is more beat up than the trees on either side. It is possible a vortex hit that tree, passed between the two homes then hit the collapsed home head on. There is a second tree behind the destroyed home that is also quite beat up. The vortex (they are short-lived, just seconds usually) may have weakened beyond that point.

Dr. Fujita used to plot the path of these vortices in his damage surveys.
1970 Lubbock Tornado Survey
Without doing an engineering study (paging Tim Marshall), the cause cannot be determined. But, I wanted to offer some plausible explanations.

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