![A ghostly-white wall cloud looms over the countryside of western Oklahoma in June. Wall clouds can be precursors to significant tornado activity if rotation is persistent.](https://www.weatherpix.com/img-get/I0000K_rXnkVjGlk/s/860/688/wsi-stm050.jpg)
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A ghostly-white wall cloud looms over the countryside of western Oklahoma in June. Wall clouds can be precursors to significant tornado activity if rotation is persistent.
Filename: wsi-stm050.tif
Copyright Gene Rhoden/Weatherpix
Copyright Gene Rhoden/Weatherpix