Module 2Case study 2

EF4 Strong Tornado Case

Hallam, Nebraska

Brian E. Smith

National Weather Service

Valley, NE

Aerial Photo over

Hallam.

11

22

33

4 4

5 5

One or Two Family Residence• DODs• 1• 2• 3• 4• 5• 6• 7• 8• 9• 10

Return to the aerial photo

Metal Building System• DODs• 1• 2• 3• 4• 5• 6• 7• 8

Return to the aerial photo

Manufactured Home Single Wide

• DODs• 1• 2• 3• 4• 5• 6• 7• 8• 9

Mobile Home FrameMobile Home Frame

Return to the aerial photo

One or Two Family Residence

One or Two Family Residence• DODs• 1• 2• 3• 4• 5• 6• 7• 8• 9• 10

Return to the aerial photo

Hardwood Trees

Hardwood Trees

• DODs

• 1

• 2

• 3

• 4

• 5

Return to the aerial photo

One or Two Family Residences

One or Two Family Residences

• DODs• 1• 2• 3• 4• 5• 6• 7• 8• 9• 10

Return to the aerial photo

One or Two Family Residences

Closeup of the Home• DODs• 1• 2• 3• 4• 5• 6• 7• 8• 9• 10

Norris School

Junior or Senior High School

Roof off classrooms

Large Span Roofs Collapsed

Junior or Senior High School

• DODs• 1• 2• 3• 4• 5• 6• 7• 8• 9• 10• 11

Summary

• Case Study of the Tornado that struck Hallam, Nebraska on May 22, 2004

• Identify the Appropriate Damage Indicator

• Assess the Degree of Damage

• Assign a final EF Scale Rating (EF4)

• Identify Construction Quality variances and adjust DOD or wind speeds accordingly

Additional Information

• Storms Prediction Center EF-Scale Website: www.spc.noaa.gov/efscale

• Texas Tech Wind Science Engineering Center: www.wind.ttu.edu/EFScale.pdf