2/16/2017 In the Eye of the Storm: Perspective From an Engineer, Meteorologist and Storm Chaser by Tim Marshall P.E. Meteorologist Presented at 2017 Tornado Summit Oklahoma City, OK February 14, 2017 1957 Began to position chase April 21, 1967 vehicles Oak Lawn, IL Tornado 1967 -Oak Lawn, IL news 1 2/16/2017 Oak Lawn Tornado Damage Destroyed mobile home park April 21, 1967 April 21, 1967 barograph trace Oak Lawn Tornado Track from Albright Middle School Rated F4 Traveled 16.2 miles @ 60 mph 33 deaths >1000 homes damaged Marvin Zeaman Drops in pressure with Belvidere http://www.weather.gov/media/lot/events/1967_Apr _Tornadoes/OakLawn_Tornado_survey.pdf and Oak Lawn tornadoes. 1969 - Won top award for tornado exhibit at science fair. 1970 – Lubbock, TX Tornado Tornado 2 2/16/2017 1970- Dr. Fujita surveyed the 1970 – Lubbock, TX Tornado tornado damage http://www.lubbocktornado1970.com/pdf /LubbockTornadoes_TetsuyaFujita.pdf Institute for Disaster 1971- Fujita Scale Research was formed at TTU https://swco-ir.tdl.org/swco- ir/handle/10605/261888 Kiesling, Peterson, Mehta, Minor, McDonald DR. TED FUJITA and the 1974- F5 Xenia, OH Tornado SuperOutbreak April 3-4, 1974 I attended his lecture at the 319 fatalities, 5,484 injuries Univ. of Chicago 11-12-74 3 2/16/2017 1974- F5 Xenia, OH Tornado 1974 – N.I.U. Meteorology Prof. Jack R. Villmow Worst damage occurred on Marshall Street ! 1976 – First Tornado Damage Survey 1976 – Lemont, IL Tornado I walked the damage path 1978 – TTU Graduate School 1978 – TTU Graduate School Saw a tornado first day in TX Edmonson, TX – May 27, 1978 4 2/16/2017 April 10, 1979 - Dr. Peterson and I April 10, 1979 – Wichita Falls Tornado prepare to chase storms Mobile home park adjacent to Hwy 287 June 3, 1980 June 3, 1980 Grand Island, NE Tornadoes Grand Island, NE Tornadoes Did aerial and ground surveys 5 2/16/2017 June 3, 1980 June 3, 1980 Grand Island, NE Tornadoes Grand Island, NE Tornadoes http://www.depts.ttu.edu/nwi/Pubs/Rep ortsJournals/ReportsJournals/D6-3-80- Tor-GrandIsland.pdf June 3, 1980 June 3, 1980 Grand Island, NE survey Grand Island, NE Tornadoes House failure modes Paths of roof planks Aug. 1980 – TTU August 10, 1980- Hurricane Allen My first hurricane chase CE student Day before hurricane Day of hurricane 6 2/16/2017 I witnessed the power of 1980- I witnessed the hurricane-force winds power of storm surge April 12, 1981 Warren, OK http://www.depts.ttu.edu/nwi/Pubs/ReportsJournals/ ReportsJournals/D8-10-80-Hurr-Allen.pdf May 22, 1981 – Binger, OK https://stormtrack.org/wordpress/wp-content/uploads/the- mesocyclone-evolution-of-the-warren-oklahoma-tornadoes.pdf 7 2/16/2017 May 22, 1981 – Binger, OK May 22, 1981 – Binger, OK http://www.depts.ttu.edu/nwi/Pubs/ReportsJournals/ ReportsJournals/D5-22-81Tor-Binger.pdf 1982 – Storm Chase Manual Classic Supercell Listed procedures on how to chase storms and film them at close range. NRC contract to study debris generated by tornadoes https://stormtrack.org/wordpress/wp-content/uploads/storm-chase-manual-1998-edition.pdf May 9, 1982 Dawn, TX May 16, 1982 Silverton, TX 8 2/16/2017 May 19, 1982 Pampa, TX #2 May 19, 1982 Pampa, TX #4 May 19, 1982 Pampa, TX #6 May 19, 1982 Tornado Tracks https://stormtrack.org/wordpress/wp- content/uploads/storm-scale-of-the-pampa-storm.pdf 1983 – Haag Engineering Co. Ice Ball Launcher 9 2/16/2017 HAIL Making Ice Balls SIZE DAMAGE THRESHOLD (IN) 1 Lightweight comp shingles 1-1/4 Heavy weight comp, wood shingles 1-1/2 Medium wood shakes 1-3/4 Concrete tiles, modified bitumen 2 Smooth built-up roofing, EPDM Ballasted built-up roofing, EPDM, metal 2-1/2 panels https://ams.confex.com/ams/pdfpapers/45858.pdf FM 4473 – Ice impact test Wood and Comp Pictorials http://haageducation.com/books-tools/ 1986 - First “portable” computer 1986 STORMTRACK MAGAZINE Lasted 25 years Now online at: http://www. stormtrack.org Getting SAO’s with my PCjr – 64K no hard drive, 8 pin dot matrix printer and 300 baud modem. 10 2/16/2017 May 1, 1988 - Carson Eads Chase Van 1996- “TWISTER” movie with star Bill Paxton At OKC premiere with Don Burgess and Jim Bellville with Oprah Winfrey Involved in the development 1978-2016 chase statistics of the new EF-scale Upgrades the ~ 800 chase days (2.1 years) original Fujita ~ 400 days of severe storms (50%) Scale using 28 damage ~ 300 tornadoes indicators. ~ 100 tornado days Adopted by the ~ 500,000 miles (625 mi/chase) NWS in 2007. ~ 10,000 hours chasing (416 day hours) http://www.depts.ttu.edu/nwi/Pubs/FScale/EFScale.pdf Does not include hurricane chases or air miles. 1978-2016 Tornado Days and Surveys My Tornado Library Over 30,000 slide images of tornadoes, chasing, and damage. Thousands of hours of video and tape recordings of chases in formats from Super8, VHS, SVHS, HiHiHi-Hi---8,8, MiniDV, and SD. Birmingham UK Tornado Thousands of papers, books, and Survey newspaper articles on tornadoes. 11 2/16/2017 Chase logs and hand drawn maps are Books, videos and files kept in notebooks – oh my! Tornado Room “Ring of Honor” Slides are labeled and sleeved Tornadic Winds: In-situ and Radar measurements at Low levels (TWIRL) 5 pods in THE 2016 SCOUT 3 TWIRL PROJECT http://www.cswr.org Team: Brandon Molyneaux, Jacob DeFlitch, and Katie Griffith 12 2/16/2017 The instrumented pod cost 6K each 2016 TWIRL PROJECT 3 DOWS Dr. Josh Wurman Dr. Karen Kosiba 3 SCOUTS Dr. Josh Wurman inside DOW-7 2016 TWIRL PROJECT 2016 TWIRL PROJECT 13 2/16/2017 I-35 4:05p HWY SULPHUR, OK 177 WYNNEWOOD CHASE SCOUT 3 MAY 9, 2016 SM DAVIS Rt. 7 SULPHUR 4:07 PM Multi-vortex I-35 4:05p tornado SW HWY 177 WYNNEWOOD SCOUT 3 DAVIS Rt. 7 SULPHUR 4:07PM – POD L deployed I-35 4:11p HWY 177 WYNNEWOOD SCOUT 3 1m DAVIS Rt. 7 SULPHUR 14 2/16/2017 I-35 4:11p 4:15 PM Pod M deployed HWY 177 WYNNEWOOD SCOUT 3 1m DAVIS Rt. 7 SULPHUR I-35 4:18p I-35 4:18p HWY HWY 177 177 WYNNEWOOD WYNNEWOOD SCOUT 3 SCOUT 3 DAVIS Rt. 7 SULPHUR DAVIS Rt. 7 SULPHUR 4:19 PM Tornado crossed Meridian Rd. 4:17 PM POD N deployed The tornado went south of all 3 pods 15 2/16/2017 4:44 PM – Multi-vortex 4:25 PM Tornado lifts and destroys house tornado forms south HWY HWY 177 4:50p 177 4:50p WYNNEWOOD WYNNEWOOD SCOUT 3 SCOUT 3 SULPHUR SULPHUR DAVIS Rt. 7 DAVIS Rt. 7 I-35 I-35 4:52 PM – Wedge just south 4:55 PM – Wedge just south 16 2/16/2017 Quickly deployed pod in Reality duplicates Hollywood front of wedge tornado V O R T E X 2 S P E C I A L E D I T I O N SCOUT 3 Thanks to Scott Peake V HWY HWY 177 4:57p 177 4:57p WYNNEWOOD WYNNEWOOD SCOUT 3 SCOUT 3 SULPHUR SULPHUR DAVIS Rt. 7 DAVIS Rt. 7 I-35 I-35 Courtesy of CSWR 1 m/s = 2.237 mph 5:00 PM Tornado approaching us. Pod hit. 89 mph 17 2/16/2017 Courtesy of CSWR Courtesy of CSWR 1 km 1 km Courtesy of CSWR Courtesy of CSWR 1 km 1 km Courtesy of CSWR Courtesy of CSWR 78mph 1 km 1 km 18 2/16/2017 Courtesy of CSWR Courtesy of CSWR 1 km 1 km Courtesy of CSWR FIRST POD HIT FOR CSWR 1 km TORNADO TRACKS by NWS I- 3 OKC Area 5 Damage KATIE SULPHUR TORNADO TORNADO Surveys 9 MILES 17 MILES LONG LONG 21 MINUTES 43 MINUTES RATED EF-4 RATED EF-3 19 2/16/2017 1999, 2003 and 2013 PATHS May 3, 1999 – Moore, OK 1 SQ. MILE Still images from video by Tim Marshall Variation of damage: F0 to F5 F-scales overlaid on aerial photo 117 118 CRITICAL CONNECTIONS Problems with foundation attachment 20 2/16/2017 Types of connections to slab Typical connection of wall to slab F indicates likely failure areas Straight-nailed studs pulled away from Studs pulled out from strapped bottom plate (May 1999) bottom plate (May 1999) Bottom plate had been secured with Scrape in slab where cut nail moved shot pins (May 1999) (May 1999) 21 2/16/2017 Cut nails were all that was left of this I returned to Moore in August 1999 and house (May 1999) examined 40 homes under construction… Five homes were bolted to their foundations (12.5%). Six homes were strapped to their foundations (15%). 29 homes were nailed or pinned to their foundations (72.5%). Building Code Anchor Bolt Placement Requirements Wood bottom plates on exterior walls shall be bolted to the foundations a maximum of 6 feet apart. A nut with washer must be tightened on each bolt. There shall be a minimum of TWO bolts per plate section. 130 12.5% foundations had bolts ( Aug. 1999) Properly bolted wall plates (Aug. 1999) 22 2/16/2017 15% of foundations had straps (Aug. 1999) Oops. Strap outside wall insulation board (Aug. 1999) 72.5% of walls were to be nailed or pinned to their foundations (Aug. 1999) Oops #2 – Straps outside of insulation board (Aug. 1999) Use of cut nails on perimeter walls Shot pinned wall plate to slab (Aug. 1999) was a code violation (Aug. 1999) 23 2/16/2017 How deep does a cut nail extend into the slab? Problems with wall attachment About a half inch if it doesn’t spall the concrete! Let-in brace helps stiffen wall (Aug.