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An '''updraft''' is a current of rising [[air]].<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref>
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An '''updraft''' is a current of rising [[air]].<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref>. Updrafts can vary in speed, from a few feet per second to 6000 feet per minute.<ref>U.S. Department of Transportation, Federal Aviation Administration. ''Balloon Flying Handbook''; p. 4-25, (2008) [http://books.google.com/books?id=khgsAq5voHMC&lpg=SA4-PA25&dq=updraft%20balloons&pg=PR2#v=onepage&q=updraft&f=false]</ref>
    
==References==
 
==References==
 
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[[category:meteorology]]
 
[[category:meteorology]]
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