Why Do Tornadoes Strike in the Same Place?
Monday’s tornado was the fourth to hit the area since 1998. While the winds of a tornado and the path that it follows might seem random, the unfortunate truth is that tornadoes are more common in some areas than in others. Moore is in ‘Tornado Alley,’ – the town experienced a tornado with winds over 300 miles per hour in 1999: the strongest winds ever recorded.
Why Moore? Tornado Alley is the area that extends from the Rockies to the Appalachians. Even though you can’t normally see it, in between these mountains is an area that’s like a river of wind. The Rocky Mountains block the moist Pacific air that would otherwise move east. Instead, cold Arctic air moves downward from the north, meeting with warm, moist air from the Gulf of Mexico.
When the warm and cold air meet, the winds that result lead to wind shear. Add some moisture, and you get the conditions for thunderstorms that are the other precursor to a tornado. It just so happens that the United States has mountains that make the perfect air funnel, and it lies between areas of cold and moist, warm air – the perfect set up for creating the majority of the world’s tornadoes.
Fewer Tornadoes in 2012/2013?
Interestingly enough, this year and last have experienced fewer tornadoes overall, which may be due to the lack of moisture, as the areas in Tornado Alley have also been in drought conditions. April and May tend to be the peak season for tornadoes, leading to the hope that the Moore tornado might be the intense finale of this year’s relatively quiet tornado season in the United States.
CBC News. Oklahoma Residents Begin to Return Home After Deadly Tornado. (2013). Accessed May 22, 2013.
Toothman, J. Tornado Science. (2013). Discovery Channel. Accessed May 22, 2013.
NOAA. Fujita Tornado Damage Scale. Accessed May 22, 2013.
Seattle Times. Key Ingredients Led to Oklahoma Tornado. (2013). Accessed May 22, 2013.
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