Colliding air masses within tornado alley make for exceptional conditions that allow for vigorously rising air, which is essential for thunderstorms. Storms in the Great Plains regularly reach 10 miles (16 kilometers) into the sky because of these conditions: 1  Winds pushing disparate air masses converge in tornado alley. 2  Colliding air, known as fronts, have nowhere to go, therefore they rise.
Apple's fiscal 2011 10-K report showed that the average size of an Apple Store has creeped up to 8,400 square feet per store, but Needham & Company analyst Charlie Wolf says that the retail stores are bulging at the seams and just aren't big enough.
Average per store selling area of supermarkets in the U.S. 2012-2014. Average per store selling area of supermarkets in the United States from 2012 to 2014 (in square feet). 1  Average weekly sales per square feet of supermarket stores in the U.S. 2012-2014 +.his statistic represents the leading U.S. retail stores by segment in 2012, based on the highest sales per square foot. With sales of 3,017 U.S. dollars per square foot, Tiffany & Co. topped the list in the luxury and accessories segment.