Draft final report, National Institute of Standards and Technology (NIST) Technical investigation of the May 22, 2011 tornado in Joplin, Missouri

Number of Warning Information Sources and Decision Making During Tornadoes

“…4,5 Total fatalities caused by tornadoes from 1950 to 2011 in the U.S. amount to 5,641, more than those by hurricanes and earthquakes combined. 6 Taking proper protective actions upon receiving tornado warnings, such as taking shelter, is a key factor to reducing casualties. 7,8 With continuous improvements in technology allowing for longer lead time, a better understanding of social mechanisms and individual behaviors centering on responses to warnings is especially important.…”

Some Considerations for the Use of High-Resolution Mobile Radar Data in Tornado Intensity Determination

“…Since there are wind speeds associated with the EF scale, damage assessors use the relevant damage indicators (DIs) and degree of damage (DoD) levels to arrive at an EF-scale category and, typically, an estimate of maximum wind speed. These ratings have been used for the study of tornado climatology across the United States and the correlation of environmental parameters with the occurrence of tornadoes of particular intensity (e.g., Kerr and Darkow 1996;Brooks and Doswell 2001;Brooks et al 2003; Thompson et al 2003Thompson et al , 2007Brooks 2004;Mead and Thompson 2011;Garner 2012); the EF scale ratings are of interest to meteorologists as well as to those in many other industries (e.g., Womble and Smith 2009;Womble et al 2009Womble et al , 2011Thampi et al 2011;Kuligowski et al 2013). For a general discussion on the history, development, advantages, and limitations of the EF scale, readers are referred to Doswell et al (2009) and Edwards et al (2013).…”

“…In addition, the EF-scale rating for a tornado ''should represent an estimate of the highest wind speed that occurred during the life cycle of the tornado'' (WSEC 2006, p. 12). Assessing damage in the field can be extremely difficult, even if there are a sufficient number and ''type'' of DIs to allow one to estimate the maximum winds that occurred; for the more intense tornadoes, there may not be adequate DIs to assess confidently an upper bound to the estimated wind speed (e.g., Kuligowski et al 2013). Since there often may be limited or no damage from tornadoes in rural areas relative to more populated locales, the frequency of violent tornadoes within tornado climatology is likely underrepresented.…”

“…The duration, variability, and full three-dimensional structure of winds of a particular magnitude, as well as debris loading (e.g., Gong et al 2006;Lewellen et al 2008), can modify the amount of damage produced by a tornado (e.g., Federal Emergency Management Agency 2012; Kuligowski et al 2013). In an examination of visual, in situ, and radar observations of a tornado that occurred in Wyoming in 2009, Wurman et al (2013) noted that very similar structures failed at significantly different wind speeds.…”

Urban downburst vulnerability and damage assessment from a case study in Argentina

“…Trees are not reliable indicators of the wind speed at failure because of differences in species, growing conditions, and heights, but they are helpful to determine the overall damage pattern of the downburst and the directions of the winds (see Kuligowski et al 2014). The downburst caused extensive damage to the tree canopy layer in Bell Ville.…”