2013 El Reno tornado

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2013 El Reno tornado
View of the tornado from the southeast at 6:28 p.m. CDT (2328 UTC) as it was nearing peak strength

View of the tornado from the southeast at 6:28 p.m. CDT (2328 UTC) as it was nearing peak strength
Date May 31, 2013
Time 6:03–6:43 p.m. CDT (UTC−05:00)
Rating EF3 tornado
Damages $35–40 million (estimate)
Casualties 8 fatalities, 151 injuries
Area affected Canadian County, Oklahoma; especially areas to the south of El Reno

During the early evening of May 31, 2013, the widest tornado in recorded history occurred over rural areas of central Oklahoma. Part of a larger weather system that produced dozens of tornadoes over the preceding days, the tornado initially touched down at 6:03 p.m. CDT (2303 UTC) about 8.3 miles (13.4 km) west-southwest of El Reno. The storm rapidly grew in size and became more violent. Remaining over mostly open terrain, the tornado did not impact many structures; however, measurements from mobile Doppler weather radars revealed extreme winds in excess of 296 mph (476 km/h) within the tornado. As it crossed Highway 81, it had grown to a record-breaking width of 2.6 miles (4.2 km). Turning northeastward, the tornado soon weakened. After crossing Interstate 40, the tornado dissipated around 6:43 p.m. CDT (2343 UTC), after tracking for 16.2 miles (26.1 km), avoiding affecting more densely populated areas near and within the Oklahoma City metropolitan area. A satellite tornado also occurred; such companion tornadoes tend to be observed with especially large and intense tornadoes.[1][additional citation needed]

The tornado killed four storm chasers, the first known deaths in the history of storm chasing.[2] Although the tornado remained over mostly open terrain, dozens of storm chasers unaware of its immense size were caught off-guard. Along Highway 81, well-known storm chaser and researcher Tim Samaras, along with his son Paul and research partner Carl Young, were killed when their vehicle was thrown either by the tornado or by a sub-vortex associated with it. Local resident Richard Charles Henderson decided to follow the storm. He was also killed while chasing the tornado in that same area.[3] Other chasers, including Mike Bettes of The Weather Channel and Reed Timmer, were either injured or had their vehicles damaged. Overall, the tornado was responsible for eight fatalities and 151 injuries.[4]

Alongside rush hour traffic, thousands of residents in Oklahoma City attempted to outrun the storm by taking to the roads in an attempt to drive out of the tornado's path. By attempting to escape the storm by vehicle, in direct contrast to the recommended plan of action, residents put themselves at great risk from the storm; had the tornado maintained itself and passed over the congested freeways, more than 500 lives could have been lost.[5]

Meteorological synopsis[edit]

Phased array radar (reflectivity; click to animate) of the series of supercell thunderstorms that impacted the Oklahoma City metropolitan area on May 31.

On May 31, 2013, a prominent mid-to-upper level trough and closed mid-level low pressure area moved east-northeastward with a lead upper low pivoting over the Dakotas and Upper Midwest region. A moderately strong polar jet moved east-northeastward over the southern Rocky Mountains to the southern Great Plains. With a broad influence of moderately strong cyclonic flow aloft, the air mass was expected to become unstable across much of the southern Great Plains through the upper Midwest and Mississippi Valley by the afternoon.[6]

Dewpoint values had ranged from the upper 60s °F (20 °C) to the lower 70s °F (20–22 °C), with temperatures in the low to mid 80s °F (27–30 °C), and CAPE values ranging from 3500–5000 J/kg. Deep layer wind shear speeds of 45–55 kt would enhance storm organization and intensity.[6] These factors, along with CAPE values in excess of 4000 J/kg and an embedded speed maxima rotating around the southern periphery of the low, made the threat of significant severe thunderstorms increasingly likely.[7] These ingredients were present ahead of a cold front extending from the low from the eastern Dakotas southwestward to western Oklahoma, and ahead of a dry line extending from western Oklahoma southward into western north and west-central Texas.[6]

The most intense severe weather activity was expected across the southern Great Plains, specifically central and eastern Oklahoma, during the afternoon hours. As such, the Storm Prediction Center issued a moderate risk of severe thunderstorms during the early morning hours of May 31 from southeastern Missouri to southwestern Oklahoma. The degree of wind shear, moisture and instability within the warm sector favored the development of discrete supercells. Very large hail and tornadoes were expected with the supercells, with the possibility of a few strong to violent tornadoes.[6] A Particularly Dangerous Situation tornado watch was issued at 3:30 p.m. CDT early that afternoon from southwestern through northeastern Oklahoma, surrounding the Interstate 44 corridor.[8][9][10] Thunderstorm activity across Oklahoma during the mid-afternoon hours was largely limited to far northern parts of the state due in part to a capping inversion that did not erode farther south until later in the day, aided by a shortwave trough that pushed into the region from the Texas Panhandle and a stronger trough located over Colorado. A quasi-linear complex of severe thunderstorms began developing near the Highway 81 corridor west of Oklahoma City between 4:00 and 4:45 p.m. CDT.

At 5:33 p.m. CDT (2233 UTC), the southernmost supercell in this complex prompted a tornado warning for Canadian County as it exhibited tornadic circulation.[11] At 6:03 p.m. CDT (2303 UTC), a large tornado touched down 8.3 miles (13.4 km) west-southwest of El Reno.[12] It ultimately attained EF3 intensity during its existence, according to ground surveys.[4] As the tornado passed south of El Reno along Highway 81, it reached an unprecedented width of 2.6 miles (4.2 km), becoming the widest known tornado ever recorded worldwide.[nb 1][12][14] At 6:28 p.m. CDT (2328 UTC), the storm began moving into more densely populated areas while maintaining its intensity. This prompted a tornado emergency for Yukon, Richland, Wiley Post Airport, Bethany, The Village, and eastern El Reno. Within minutes, the tornado turned northeast and soon passed directly over Interstate 40 around 6:42 p.m. CDT (2342 UTC).[15] Shortly thereafter, the tornado lifted as it neared Banner Road. Overall, the tornado was on the ground for 40 minutes along a 16.2 miles (26.1 km) path.[14]

Intensity[edit]

Video of several sub-vortices within the tornado.

The intensity of the tornado has been a subject of internal debate within the National Oceanic and Atmospheric Administration. The agency utilizes the Enhanced Fujita Scale to rate and assess tornado intensity based on the damage left behind. This excludes the use of supplementary measurements, such as those from mobile radar, in concluding a tornado's intensity.[citation needed] Initially receiving an official EF3 rating based on damage, the El Reno tornado was subsequently upgraded to a radar-estimated EF5 rating, the highest on the scale, based on data from a mobile radar. The University of Oklahoma's RaXPol Doppler weather radar, positioned at a nearby overpass, measured winds in excess of 296 mph (476 km/h). These winds are considered the second-highest ever measured worldwide, just shy of the 301 mph (484 km/h) recorded during the 1999 Bridge Creek–Moore tornado.[16][17] These occurred in small sub-vortices along the south side of the main vortex. The two most intense vortices occurred north and east of the intersection of 10th Street and Radio Road, about 3 miles (4.8 km) southeast of El Reno.[18][19] The main funnel is believed to have had radar-estimated EF4 winds, with wind speeds around 185 mph (298 km/h). Radar-estimated EF5 winds were only found aloft and in the smaller vortices that rotated around this funnel at 110 mph (180 km/h).[16]

Rick Smith, the warning coordinating meteorologist at the National Weather Service Weather Forecast Office in Norman, Oklahoma stated that this tornado was among a "super-rare" category within the EF5 ranking, a type of tornado rarely seen. Smith also stated that it was fortunate the tornado did not track into more densely populated areas, "this would have been ... I don't even want to imagine what it would have been."[18] William Hooke, a senior policy fellow at the American Meteorological Society stated that, "[Oklahoma City] dodged a bullet...You lay that path over Oklahoma City, and you have devastation of biblical proportions."[20]

On August 30, the National Weather Service office in Norman once again revised the intensity of the El Reno tornado, downgrading it from an EF5 to an EF3. Keli Pirtle, a Public Affairs worker at the National Oceanic and Atmospheric Administration, stated that, "despite the radar-measured wind speeds, the survey team did not find damage that would support a rating higher than EF3. While the wind measurements from the mobile radars are considered reliable, NWS policy for determining EF-ratings is based on surveys of ground damage."[21] The lack of EF5 damage was likely a result of the rural nature of the area, as the sub-vortices that contained the EF5 wind speeds did not impact any structures.[22]

Storm chaser incidents[edit]

Storm spotter tribute to Tim Samaras, Paul Samaras, and Carl Young across the Plains on June 2

The tornado's unusual behavior consisting of these simultaneous occurrences: abrupt changes in direction, rapid enlargement to a width of 2.6 miles in diameter in about 30 seconds, swift increase in forward motion from about 20 mph to as much a 55 mph within a few minutes, multiple vortices within, and an expansive translucent outer circulation without a full condensation funnel whilst being surrounded and obscured by precipitation made it a worst case scenario for storm chasers. Several professional and amateur chasers were caught off guard and impacted by the tornado.[23] Many were located in a region northeast of the tornado, which was both in the direction of travel of the tornado and in an area known as the "bear's cage." Chasers can generally get a clear view of the tornado from that area after traversing precipitation; however, it places them at great risk and with little time to react should the storm take a left turn.[24]

In the case of El Reno, the wrapping rain bands also led not to a narrow corridor of clear air close to the tornado rather these rotating curtains of rain were the outer circulation of the tornado itself. Former Discovery Channel storm chaser Tim Samaras (an engineer), his son Paul Samaras (a photographer), and Tim's longtime chase partner Carl Young (a meteorologist), all professional storm chasers with the TWISTEX project, were caught directly by the tornado and all three died in their vehicle (two were ejected).[25] Normally, Samaras drove a reinforced three-quarter ton truck optimized for hail protection and stability in high winds; however, on May 31 he was driving an unmodified Chevrolet Cobalt, a subcompact vehicle with three 45-lb barometric probes in the trunk likened by one TWISTEX chaser to a "pizza delivery car", making it much less suited to high winds and rain-slicked backcountry dirt roads. It was also underpowered, which hampered their escape in the strong inflow winds.[26] They are the first known tornado-related deaths of either recreational storm chasers or scientific researchers.[27]

Mike Bettes, a meteorologist for The Weather Channel, was also caught in the storm. His sport utility vehicle was severely damaged, having been thrown about 200 yards (180 m); the driver was left with a broken neck, fractured vertebrae, and several broken ribs while Bettes and the other passenger sustained minor injuries.[24][28][29] Meteorologist Emily Sutton and storm chaser Kevin Josefy of Oklahoma City NBC affiliate KFOR-TV (channel 4) were also caught in the path of the storm; their vehicle was damaged by debris hurled by the tornado.[30] Another storm chaser, along with his father and a friend, sought refuge under an overpass (an action strongly discouraged in these situations) when the tornado changed direction.[31] Near Union City, debris from a barn destroyed by the tornado struck the vehicle of Brandon Sullivan and Brett Wright, breaking their windshield; they escaped without injury.[32] The hood of Reed Timmer's Dominator 2, a vehicle allegedly designed for intercepting tornadoes, was torn off.[33] Chaser Dan Robinson received injuries after being enveloped within the outskirts of the tornadic circulation. He escaped and was a few hundred meters ahead of the TWISTEX crew and is believed to be the last person to see the Samaras' and Young.[34] Another vehicle containing three people, including University of Oklahoma meteorology students and a television station employee was also struck by the tornado which lofted their vehicle and ejected one of the occupants.[citation needed]

Response[edit]

In the wake of the storm chaser deaths, Kansas Emergency Management Association president Brian Stone called for there to be regulations put on future storm chasing; however, he stated that there are questions as to how it would actually be implemented. AccuWeather Senior Vice President Mike Smith urged against overreacting to their deaths, citing that they were the first chasers to be killed in 40 years of the practice and that chasing as a whole is a significant source of real-time and research information.[24]

On June 2, dozens of members of the storm chasing community coordinated a tribute to Tim Samaras, Paul Samaras, and 45-year-old Carl Young. Using GPS transponders, they aligned themselves to spell out their initials in North Dakota, South Dakota and Nebraska for many hours.[35] The Discovery Channel scheduled a special tribute episode of Storm Chasers titled Mile Wide Tornado: Oklahoma Disaster on June 5, both honoring the three chasers and covering the events of the EF5-rated tornado that struck Moore and portions of southern Oklahoma City eleven days earlier on May 20.[36] The November 2013 issue of National Geographic, for its featured cover story, paid tribute to Tim Samaras, a National Geographic Explorer funded in part by the Society, and featured a detailed scientific analysis of the tornado itself.[37]

A team of scientists and veteran chasers embarked on a crowd-sourcing survey project to gather storm chaser information, including video and photographic recordings and GPS logs, in order to piece together precisely what happened. It is, as of February 2014, the largest such visual data set ever collected on a tornado. The chaser information is compiled with radar and lightning data and the project is intended to eventually expand to a standardized open access database covering future events.[38]

Casualties and impact[edit]

A destroyed home about 4 miles (6.4 km) west of Highway 81 (southwest of El Reno).

Since the tornado remained over mostly open terrain, damage was relatively light (although still significant in isolated locations) in comparison to its extreme intensity. Surveys from the National Weather Service revealed that structures in its path sustained EF3-level damage at most.[39] The El Reno campus of the Canadian Valley Technology Center was largely destroyed, with damage from the school's four buildings estimated at $35–40 million.[40][41] The Oklahoma City West Livestock Market was regarded as a "war zone," sustaining extensive damage. One farmstead, consisting of a large barn, a cattle barn, three machine sheds, granaries, and the owner's home, was completely destroyed.[42] At least 29 buildings and 40 vehicles were damaged by the tornado, with repairs in El Reno expected to take at least a year.[43]

On June 1, the American Red Cross set up a shelter at the Redlands Community College in El Reno for victims of the storm.[44] The following day, Oklahoma Governor Mary Fallin toured damaged areas of El Reno. Due to the previous tornadoes on May 20, a state of emergency was already in place for the affected areas, allowing residents to quickly obtain emergency assistance.[45] Residents left homeless were provided with temporary housing constructed from shipping containers. Each container was fitted with a kitchen, bedroom, living room, and bathroom.[46]

Overall, eight people lost their lives as a result of the tornado, all of whom were killed in vehicles.[47] Local hospitals in Oklahoma City, including OU Medical Center and INTEGRIS Southwest Medical Center, and Mercy Hospital in El Reno, reported receiving at least 115 injured, including five critical patients.[48][49] Overall, 151 injuries were attributed to the tornado.[4]

Evacuations[edit]

Satellite image of Oklahoma City on June 2 depicting the ground scar left behind by the tornado.

As the tornadoes approached the Oklahoma City metro, thousands of residents decided to leave the area for safety, possibly due to the still fresh memories of the devastation caused by the May 20 Moore tornado.[49] Already congested with rush hour traffic, Interstates 35, 40, 44 and 240, became "parking lots" as the storms neared.[49][50] Residents reported the highways to be a scene of chaos, "people were going southbound in the northbound lanes. Everybody was running for their lives."[49] It has been suggested that the evacuation was partially caused by a controversial call to action on-air by KFOR-TV chief meteorologist Mike Morgan, who suggested on-air that residents without underground storm shelters or safe rooms get into their cars and evacuate south of the track.[28] This advice was contrary to the recommended plan to go to an interior room, bathtub or closet with no windows if no underground shelter is available, such as a basement. These locations are typically much safer than an automobile in tornadic winds.[51] Dr. Jeff Masters of Weather Underground stated that had the tornado tracked directly over one of the congested highways, the death toll could have easily exceeded 500.[5]

See also[edit]

Notes[edit]

  1. ^ Though the El Reno tornado officially ranks as the widest on record, Doppler on Wheels measurements of the 1999 Mulhall, Oklahoma tornado indicated that it may have been 4.3 mi (6.9 km) wide.[13]

References[edit]

  1. ^ Wurman, Joshua; K. Kosiba, P. Robinson, T. Marshall (January 2014). "The Role of Multiple-Vortex Tornado Structure in Causing Storm Researcher Fatalities". Bulletin of the American Meteorological Society 95 (1): 31–45. doi:10.1175/BAMS-D-13-00221.1. Retrieved March 24, 2014. 
  2. ^ Ian Livingston; Mark Ellinwood (June 3, 2013). "The storm chaser dilemma and choice to sit out the May 31 Oklahoma City tornadoes". The Washington Post. Retrieved February 22, 2014. 
  3. ^ Nolan Clay (June 3, 2013). "Oklahoma storms: Amateur storm chaser took photo of tornado that killed him". The Oklahoman. Retrieved June 4, 2013. 
  4. ^ a b c Mark Johnson (September 1, 2013). "Historic El Reno, OK tornado is downgraded by National Weather Service". NewsNet5. Retrieved September 1, 2013. 
  5. ^ a b Jeff Masters (June 1, 2013). "A Night of Tornado Chaos in Oklahoma City: 9 Killed, 71 Injured". Weather Underground. Retrieved June 1, 2013. 
  6. ^ a b c d "May 31, 2013 0600 UTC Day 1 Convective Outlook". Storm Prediction Center. May 31, 2013. Retrieved August 4, 2013. 
  7. ^ Dial (May 31, 2013). "Mesoscale Discussion 908". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved June 1, 2013. 
  8. ^ "Particularly Dangerous Situation (PDS) Tornado Watch 262". Storm Prediction Center. May 31, 2013. Retrieved February 4, 2014. 
  9. ^ "Special Weather Statement: Tornado Watch". National Weather Service Norman, Oklahoma. May 31, 2013. Retrieved August 4, 2013. 
  10. ^ "Special Weather Statement: Tornado Watch". National Weather Service Tulsa, Oklahoma. May 31, 2013. Retrieved August 4, 2013. 
  11. ^ "Special Weather Statement: Tornado Warning". National Weather Service Office in Norman, Oklahoma. Iowa Environmental Mesonet. May 31, 2013. Retrieved June 1, 2013. 
  12. ^ a b "Central Oklahoma Tornadoes and Flash Flooding – May 31, 2013". National Weather Service Office in Norman, Oklahoma. National Oceanic and Atmospheric Administration. June 1, 2013. Retrieved June 1, 2013. 
  13. ^ Wurman, Joshua; C. Alexander, P. Robinson, and Y. Richardson (January 2007). "Low-Level Winds in Tornadoes and Potential Catastrophic Tornado Impacts in Urban Areas". Bulletin of the American Meteorological Society (American Meteorological Society) 88 (1): 31–46. Bibcode:2007BAMS...88...31W. doi:10.1175/BAMS-88-1-31. Retrieved June 4, 2013. 
  14. ^ a b "Update On May 31 El Reno Tornado". National Weather Service Office in Norman, Oklahoma. National Oceanic and Atmospheric Administration. June 4, 2013. Retrieved June 4, 2013. 
  15. ^ "Special Weather Statement: Tornado Warning". National Weather Service Office in Norman, Oklahoma. Iowa Environmental Mesonet. May 31, 2013. Retrieved June 1, 2013. 
  16. ^ a b Jeff Masters (June 4, 2013). "Largest Tornado on Record: the May 31 El Reno, OK EF-5 Tornado". Weather Underground. Retrieved June 4, 2013. 
  17. ^ "Doppler On Wheels". Center for Severe Weather Research. 2010. Retrieved June 4, 2013. 
  18. ^ a b Bryan Painter (June 4, 2013). "El Reno tornado is 'super rare' national record-breaker". Norman, Oklahoma: News OK. Retrieved June 4, 2013. 
  19. ^ A. Edwards (June 4, 2013). "El Reno, Union City tornado widest tornado on record". KFOR-TV. Retrieved June 4, 2013. 
  20. ^ Sean Murphy (June 4, 2013). "El Reno, Oklahoma Tornado Believed To Be Widest Twister On Record". Associated Press. Oklahoma City, Oklahoma: Huffington Post. Retrieved June 5, 2013. 
  21. ^ Nate Johnson (August 31, 2013). "NWS releases statement about El Reno tornado rating". Digital Meteorologist. Retrieved September 21, 2013. 
  22. ^ "Storm Events Database: May 31, 2013 Tornado". National Climatic Data Center. National Oceanic and Atmospheric Administration. May 31, 2013. Retrieved February 25, 2014. 
  23. ^ Sean Murphy and Solleen Slevin (June 3, 2013). "Storm Chasing Critical, Profitable and Dangerous". Associated Press. Oklahoma City, Oklahoma: ABC News. Retrieved June 4, 2013. 
  24. ^ a b c Stan Finger (June 4, 2013). "Storm chasers’ deaths in Oklahoma tornado prompt questions, calls for regulation". The Kansas City Star. Retrieved June 4, 2013. 
  25. ^ Padilla, Anica (June 2, 2013). "Colorado storm chaser Tim Samaras killed in Oklahoma tornado along with son, longtime partner". KMGH. Retrieved June 2, 2013. 
  26. ^ Brantley Hargrove (August 29, 2013). "Legendary Tornado Chaser Tim Samaras' Last Ride". Miami New Times. p. 2. Retrieved August 31, 2013. 
  27. ^ Kelly B. Kissel and Thomas Peipert (June 3, 2013). "3 veteran storm chasers killed by Oklahoma tornado". San Francisco Chronicle. Retrieved June 4, 2013. 
  28. ^ a b Samenow, James (June 1, 2013). "The day that should change tornado actions and storm chasing forever". The Washington Post. Retrieved June 1, 2013. 
  29. ^ "Weather Channel vehicle tossed by tornado". WVVA. May 31, 2013. Retrieved May 31, 2013. 
  30. ^ A. Edwards and Emily Sutton (May 31, 2013). "Emily Sutton, photographer Kevin Josefy have very close call with El Reno tornado". KFOR-TV. Retrieved June 4, 2013. 
  31. ^ Sarah Stewart (June 3, 2013). "Amateur storm chaser survives tornado under overpass". KFOR-TV. Retrieved June 4, 2013. 
  32. ^ Beth Stebner (June 1, 2013). "‘Duck down!’ Daredevil storm chasers get too close to tornado, struck by debris from destroyed barn". New York Daily News. Retrieved June 5, 2013. 
  33. ^ B. White (June 1, 2012). "The Weather Channel’s "Tornado Hunt 2013" vehicle flips over while chasing May 31 tornadoes". KFOR-TV. Retrieved June 4, 2013. 
  34. ^ Hargrove, Brantley (Aug 29, 2013). "The Last Ride of Legendary Storm Chaser Tim Samaras". Dallas Observer (Dallas, TX). Retrieved 2013-08-29. 
  35. ^ Adam Taylor (June 2, 2013). "Storm Chasing Community Pays Tribute To Tim Samaras". Business Insider. San Francisco Chronicle. Retrieved June 2, 2013. 
  36. ^ Chiderah Monde (June 4, 2013). "‘Stormchasers’ tribute episode to honor stars killed in Oklahoma tornado". New York Daily News. Retrieved June 5, 2013. 
  37. ^ Robert Draper (November 2013). "The Last Chase". National Geographic Society. Retrieved February 20, 2014. 
  38. ^ El Reno Survey "El Reno Survey - A Survey of the tornado of 31 May 2013". 2014. Retrieved February 20, 2014. 
  39. ^ Bryan Painter and Silas Allen (June 4, 2013). "El Reno tornado is 'super rare' national record-breaker". The Oklahoman. Retrieved June 5, 2013. 
  40. ^ Manny Fernandez (June 2, 2013). "Oklahoma Campus, Ravaged by a Tornado, Draws Attention to Storm Shelters". El Reno, Oklahoma: The New York Times. Retrieved June 4, 2013. 
  41. ^ "Rebuilding Starts In El Reno". KOKH-TV. June 13, 2013. Retrieved June 14, 2013. 
  42. ^ "OK Insurance Commissioner Tours El Reno Damage". KOKH-TV. June 3, 2013. Retrieved June 5, 2013. 
  43. ^ Heather Hope (June 21, 2013). "El Reno Mayor Foresees Long Road To Recovery After May Tornado". News 9. Retrieved June 23, 2013. 
  44. ^ "Red Cross Opens Shelters For Storm Victims". KOKH-TV. June 1, 2013. Retrieved June 5, 2013. 
  45. ^ "Fallin tours El Reno damage". KOKH-TV. June 2, 2013. Retrieved June 5, 2013. 
  46. ^ "El Reno tornado victims get unusual temporary housing". El Reno, Oklahoma: KOCO. June 19, 2013. Retrieved June 23, 2013. 
  47. ^ "Annual U.S. Killer Tornado Statistics". Storm Prediction Center. National Oceanic and Atmospheric Administration. June 10, 2013. Retrieved June 14, 2013. 
  48. ^ "12 Dead in Aftermath of Destructive Tornadoes". News West 9. June 1, 2013. Retrieved 1 June 2013. 
  49. ^ a b c d "Body of 4-year-old boy found in river after Oklahoma tornado outbreak". Associated Press. Fox News. June 2, 2013. Retrieved June 2, 2013. 
  50. ^ "As tornadoes neared, drivers hit the road – with deadly results". NBC News. May 31, 2013. Retrieved June 1, 2013. 
  51. ^ Roger Edwards (2013). "Tornado Safety". Storm Prediction Center. National Oceanic and Atmospheric Administration. Retrieved June 1, 2013. 

External links[edit]