Meteorologists upgraded the strength of the tornado that ripped through Moore, Okla. to a category E-F5, the highest level; the storm harbored vastly more energy than the atomic bomb dropped on Hiroshima. 

Monday's E-F5 twister that ravaged the Oklahoma City suburb ranged from eight to more than 600 times as powerful as the Hiroshima bomb, according to calculations by five separate meteorologists contacted by the Associated Press. Most of the estimations for the energy released during the 40-minute storm were towards the high end of the spectrum. Calculations were based on energy measured in the air and then multiplied over the size and duration of the storm.

Tuesday the National Weather Service upgraded the storm to an E-F5 for wind speed and breadth, as well as severity of damage. The storm was 1.3 miles wide and 17 miles long. Winds speeds were estimated to be as high as 210 mph and the death toll so far is 24, including at least nine children. The number of deaths is expected to rise as bodies are recovered from the wreckage.

The U.S. sees an average of one E-F5 strength tornado a year; Monday's E-F5 was the first in two years. An E-F5 tornado generates the strongest winds on earth, stronger than a hurricane. In 1999 an E-F5 that also struck Moore had wind speeds measured by radar as high as 302 mph, the strongest winds ever measured, Jeff Masters, meteorology director for Weather Underground, told the AP.

America's Great Plains is the "best place on Earth" for the formation of violent storm systems, Pennsylvania State University meteorology professor Paul Markowski told the AP. The cold, low pressure weather systems coming from the Rocky Mountains collide with warm, moist air travelling up from the Gulf of Mexico, creating the perfect conditions for tornadoes.

Of the 60 E-F5 tornadoes since 1950, Oklahoma and Alabama have been struck seven times each, according to the AP.

The New York Daily News has published stunning before and after aerial photos that show entire blocks of houses completely decimated by the power of the storm.