Observations of the Influence of Hilly Terrain on Tornado Path and Intensity from the Damage Investigation of the 2014 Tornado in Mayflower, Arkansas

摘要

Post-storm damage investigations of the EF4 tornado which struck Mayflower, AR in April 2014 is reported and utilized to study the influence of hilly terrain on the tornado's behavior. Preliminary investigations revealed that the damage in the hilly areas is from EFO to EF3 and in flat areas the damage is rated to be EF2 to EF4. Furthermore, local investigation shows that disruption of the tornadic flow near ground level by the hilly terrain leads to reduction of structural damage. From the observed damage, it is postulated that the hilly regions can effectively produce a sheltering effect, reducing the damage to structures within a region on the leeward side. It is also shown that the tornado's path is diverted by the presence of hills, which the tornado attempts to travel around rather than over.