Lessons Learned: How Changes in Code, Construction and Preparedness Affected Tornado Damage in Moore, Oklahoma, 1999 to 2013

On May 3, 1999, an F5 tornado struck Moore, Oklahoma causing loss of life and destruction of property. On May 8, 2003, an F4 tornado struck Moore, Oklahoma. On May 20, 2013, Moore was struck by an EF-5 tornado with a similar path to the 1999 and 2003 twisters. This paper will compare our observations of damage caused by the 2013 tornado event to the damage documented by available sources during the 1999 and 2003 outbreaks. This paper will also review the history of the local building codes and ordinances and discuss their impact on the damage observed. The scope will include a summary of case studies of detailed damage evaluations in which construction defects and code variations may have contributed to the observed damage.