2013 El Reno Tornado Damage Survey

Image of vegetation damage near the location where the highest doppler velocities were recorded more than 400ft above the ground. The tornado was given an EF5 rating less than 36 hours after dissipating solely due to mobile doppler radar velocities between 290 and 336mph, possibly the strongest ever recorded (AMS, 2013). The tornado was later downgraded to an EF3 due to a lack of EF5 damage indicators.

□ On May 31, 2013, a train of violent supercell thunderstorms erupted in the sky to the west of Oklahoma City. In the city suburb of Moore, rain began to fall over the tangled remains of homes and businesses obliterated less than two weeks earlier by a catastrophic EF5 tornado. Meteorologists at the National Weather Service recognized the tell-tale signs of a rotating mesocyclone on radar, and reports from storm chasers near the community of El Reno quickly verified the presence of a large, nebulous mass of clouds that had spun down to the ground. A rare tornado emergency was issued for the area a second time.

An unusually large number of storm chasers, both amateur and seasoned, drove down the perfect grid of county roads to the south of El Reno to film the ensuing storm. Like many large tornadoes, the El Reno storm began with a series of transient funnels beneath a rapidly rotating mesocyclone. Heavy rain left few good angles to film the storm, so most chasers concentrated near Highway 81 just northeast of the tornado. As the storm progressed slowly to the east-southeast it underwent a period of explosive strengthening. The already large tornado suddenly doubled in size in less than one minute (many say less than 30 seconds) to over two miles in width. Footage from multiple storm chasers showed a sudden increase in surface winds well away from the visible funnel. Near the intersection of Choctaw Avenue and SW 15th Street, two vehicles were engulfed by the storm, killing both drivers. One of the men killed, Richard Henderson, became the first amateur storm chaser fatality in history.

Storm chaser Richard Henderson sent this photograph to a friend several minutes before he was killed by the tornado on SW 15th Street. The same friend was on the phone with Henderson when debris began to strike the chaser’s car. Moments later, the line went dead (Kelly, 2013).

Trees along SW 29th Street were damaged and a piece of timber pierced 11 inches (measured) into the ground. The distance of visible damage along Highway 81 was 2.5 miles, although extreme straight line winds blurred the distinction. All of the damage visible from Highway 81 was in the EF0 to EF2 range, although wide spacing between buildings and trees left few reliable damage indicators.

A Weather Channel vehicle driving on Highway 81 was impacted by a violent wind feature, causing it to tumble through an adjacent field (initial reports stated the car travelled 200ft while later broadcasts reported 200 yards). All of the vehicle’s passengers were injured to some degree but most were able to walk away from the wreckage. Around this time, the tornado was completing an unexpected turn to the northeast. Highly knowledgable storm chasers were caught off guard by the storm’s size and unpredictability. A motorist due east of the Weather Channel crew was killed by the tornado at the intersection of Alfadale Road and Reno Street. Along SW 10th Street, a white car carrying three professional storm chasers was swept off the road west of Radio Road. Unlike the Weather Channel vehicle, the car driven by Tim Samaras was hurled 650 yards through the air at a high rate of speed (AMS, 2013). The three chasers, likely with cameras in hand, were all killed in the “unsurvivable” wreck. Several minutes later, the tornado swept across the I-40, killing a young mother and her infant son in a car hurled from the freeway. Forty minutes after first forming, the tornado weakened and dissipated.

I surveyed the damage from the El Reno tornado and interviewed local residents on June 4th and 5th. Photographs from my survey are shown below, and my final analysis can be found at bottom.

*In August of 2013, the El Reno tornado was officially downgraded to an EF3 by the National Weather Service (Querry/NWS, 2013).

A home just south of SW 15th Street along Highway 81 experienced EF1 damage despite being near the geographic center of the storm. The tornado’s multi-vortex nature meant that most of the damage swath encountered winds in the EF1 and EF2 range. The tornado’s first two fatalities occurred in two vehicles a mile west of Highway 81 along SW 15th Street (KFOR, 2013).

Wheat crop was blown to the ground in swaths approximately 50ft wide a half mile east of Highway 81 on SW 15th Street.

Fence posts adjacent to homes that experienced EF1 and EF2 damage were generally only lightly damaged. In other areas they were bent to the ground or removed entirely. In some instances, metal stakes were twisted due to bursts of winds from various directions.

A home on Alfadale Road suffered severe internal damage but was left largely standing, like most of the homes in the area. One survivor who was staying with a relative on SW 29th Street said that the tornado “lasted about five minutes, but the worst of it happened in the first 30 seconds when every window shattered at the same time.”

A home on Alfadale Road experienced EF2 damage. A motorist in a vehicle at this intersection became the storm’s third fatality.

A blizzard of dry plant materials was caught by standing fences along Radio Road.

View northeast at the intersection of Radio Road and 10th Street, where the most intense winds were recorded by mobile doppler radar. While analysis is ongoing, velocities between 290 and 336mph were recorded as a single, exceptionally powerful sub-vortex slingshotted around the south side of the tornado at 177mph. The peak winds occurred on the eastern edge of the vortex where all of the rotational velocities combined. While of record intensity, the peak winds were found 110 yards above the surface and would have impacted a standing structure for only half a second (AMS, 2013).

10th and Radio Road was marked by a sign placed after the tornado to direct local traffic.

The only tree near the intersection of 10th and Radio Road was stripped of leaves and damaged in a fashion consistent with past EF4 tornadoes.

Vegetation was blown to the ground and strewn with small pieces of debris, including fragments from destroyed vehicles. Metal fence posts were bent to the east-northeast or absent entirely from the ground. The gravel along 10th Street was blown almost completely away in areas affected by sub vortices. This is where a vehicle driven by Tim Samaras was recovered.

A fence was ripped from its posts and left in a tangled mass a half mile northeast of 10th and Radio Road.

A vehicle carrying storm chasers Tim Samaras, Paul Samaras and Carl Young was swept off 10th Street approximately 545 yards west of Radio Road. The car was thrown more than 650 yards, killing the three occupants (AMS, 2013). According to ABC News, Tim Samaras was found in the front seat whereas the other two passengers were ejected from the vehicle and found up to a half mile away. DOW observations at the time indicated that an intense sub-vortice with a forward speed of 177mph impacted the vehicle unexpectedly from the north (AMS, 2013). (Image by Jason Morris)

Area near 10th Street where the chase vehicle was swept off the road.

Flattened wheat crop just south of 10th Street.

Tree damage near where the chase vehicle was overtaken by the storm. Trees 100ft to the north on the other side of 10th Street were damaged but not defoliated. Flooding carved deep ditches into areas that were previously flat fields.

A quarter mile south of the I-40, an RV company was severely damaged in the tornado. A vehicle from the facility was thrown several hundred yards. Most of the powerlines along N2880 Road were snapped just above ground level.

Some of the most severe vegetation damage appeared to be along the I-40, north of where the peak doppler velocities purportedly occurred.

A livestock trailer was blown over 300 yards to the south from a complex across the freeway and left tangled in the remains of a fence.

View of the destroyed OKC West Livestock Market where the trailer originated.

Debris in a wind-damaged field just south of the I-40.

Tree damage just south of the I-40 near the OKC West Livestock complex. The tornado’s massive size and slow movement would have exposed many areas to tornadic winds for greater than five minutes, though peak velocities occurred only in suction spots.

Extremely heavy rainfall on the day of the tornado led to widespread flooding in the affected areas. Visible here is the OKC West Livestock Market and a pool of water that trapped large pieces of debris, including sections of broken powerlines.

Closer view of the destroyed livestock complex. Dozens of large animals were killed throughout the tornado’s path, leaving the smell of rotting flesh several days later.

Heavy tree damage just north of OKC West.

Deep impact mark on a hillside adjacent to the I-40. Several vehicles were swept from the freeway in this area, resulting in two fatalities.

Personal Damage Survey Conclusions:

Due to my belief that the Enhanced Fujita Scale grossly underestimates winds in violent tornadoes, the wind ranges I utilize are based on my research, discussions with wind engineers and comparisons between known surface readings and adjacent damage indicators in past tornadoes. My wind estimates are significantly higher than those employed by the National Weather Service.

Peak Intensity: EF4 (≈220mph)

□ The most intense damage occurred to vegetation in a swath of varying width from an area commencing just west of the intersection of 10th Street and Radio Road and ending at the I-40. Steel fence posts were bent to the ground by winds alone and not debris impacts. Powerlines were sheared just above ground level, vehicles were thrown over 200 yards and surface crops were severely damaged and bent to the east-northeast. The most intense structural damage likely occurred to the OKC West Livestock Market just north of the I-40 and several homes west of Highway 81. The most intense structural damage was consistent with winds in the EF3 range. The scarcity of trees and buildings left few reliable damage indicators, but no EF5-level vegetation damage was noted.

□ While the tornado has been deemed the “second strongest” in recorded history due to extreme doppler velocities, this claim is completely unfounded. Few violent tornadoes are ever tracked by mobile doppler radar, so the available readings are not an objective method of classification.

□ While the tornado is being called the “widest” in history, this claim is also unfounded. The 1999 Mulhall tornado likely left a significantly wider damage path. In terms of violent tornado damage, the damage swath from the 2013 El Reno tornado was narrower than many documented tornadoes, including the 2011 Joplin tornado.

The width of EF0+ damage along Highway 81 was 2.55 miles in width, as measured by the distance between the northernmost and southernmost instances of missing shingles and downed tree branches. The southern margin was 300 yards south of SW 29th Street and northern margin was just north of 10th Street. Straight line wind damage was found in areas unaffected by the tornado, so the exact damage contours were impossible to ascertain.

The vegetation damage from the El Reno tornado was noticeably less intense than the damage caused by the 2013 Moore tornado. Few trees were debarked in El Reno, whereas all of the trees in the core damage path of the Moore tornado near County Edge Drive were completely stripped of bark and branches.

The List of the Strongest Tornadoes Ever Recorded (Pre-1970): Part II

Vehicle damage is one way to ascertain the intensity of historical tornadoes, particularly since cars built pre-1960 were significantly heavier than modern light-weight vehicles. At left, extreme vehicle damage following the 1953 Beecher tornado (Image from the Flint Public Library). At center, a destroyed car after the 1956 Hudsonville tornado (Image by Thelma Bakker). At right, a truck stripped to its frame following the catastrophic Udall tornado of 1955.

□ While nowhere near definitive, objectivity is attempted through the use of damage photographs, reliable survey reports and fatality statistics. Unverified accounts, vague newspaper descriptions and damage figures are not considered. Tornadoes that occurred before 1880 and tornadoes that caused less than 10 deaths are excluded to eliminate the thousands of rural storms that failed to attract significant media attention. Little to no photographic evidence makes the inclusion of some past tornadoes unfeasible without further information.

Click to see Part I.

The list of the strongest tornadoes from 1880 to 1969:

1. Sherman, Texas – May 15, 1896

2. De Soto/Murphysboro/West Frankfurt, Illinois – March 18, 1925

3. New Richmond, Wisconsin – June 12, 1899

4. Beecher, Michigan – June 8th, 1953

5. Hudsonville, Michigan – April 3, 1956

6. Tupelo, Mississippi – April 5, 1936

7. Udall, Kansas – May 25, 1955

8. Pomeroy, Iowa – July 6, 1893

9. Woodward, Oklahoma – April 9, 1947

10. Scott County, Mississippi – March 3, 1966

11. Ruskin Heights, Missouri – May 20, 1957

12. Snyder, Oklahoma – May 10, 1905

13. Colfax, Wisconsin – June 4, 1958

14. Gans, Oklahoma – January 22, 1957

15. Winston County, Alabama – April 20, 1920

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7. Udall, Kansas – May 25, 1955

The Udall tornado caused the highest death toll in a US town with a population under 1,000. The town’s block-long business district was wrecked, whereas homes immediately to the south were swept completely away.

□ On the evening of May 25, 1955, a powerful supercell thunderstorm was edging northward near Ponca City, Oklahoma. After spawning a tornado that took 20 lives in the town of Blackwell, the storm produced another tornado that touched down near the Kansas border just before 10pm. Witnesses in the area reported that the tornado, which was made visible by near constant lightning, was approximately a quarter mile wide early in its development (NWS Storm Reports). The storm widened and strengthened as it moved northward, eventually expanding to more than half a mile in diameter. Maps from the time show the tornado traveled almost due north, but damage patterns indicate the tornado made a turn to the northeast as it roared towards the tiny town of Udall, which had only 600 residents (LIFE, 1955). The town’s population was within the boundaries of a tornado watch but a slight bureaucratic delay meant that the alert was not issued until 10:08pm. As a result, most residents who watched the 10 o’clock news were told that all advisories had been lifted (Smith, 2010). Many residents were in bed at 10:25pm, the moment the storm struck.

As the tornado reached the southwestern edge of town, it devastated the local high school and hurled vehicles from nearby houses more than a quarter mile. A massive electrical arc lit up the sky as the tornado struck a power station on 3rd Street, causing the entire town to disappear into darkness. The roar of the approaching storm gave many residents valuable time to seek shelter but the intensity of the winds below 2nd Street left nowhere safe to take cover. Rows of homes were swept completely away as the core of F5 winds passed just south of the town’s commercial strip (LIFE, 1955). The ensuing blizzard of high velocity debris killed people who attempted to run towards the few underground storm caves in town, including a couple and their two children (Raw Data Report, 1955). After leveling the town hall, the tornado crossed the railroad tracks that bisect the center of Udall and obliterated buildings in a neighborhood to the northeast. A nursing home on East Lewis Street was destroyed, leading to multiple fatalities. After exiting town, the tornado left a wide streak of scoured vegetation. (LIFE, 1955). A total of 75 people were killed in Udall, and another five lost their lives in a home south of town.

When the final people succumbed to their injuries, 13% of the town’s population was dead. There were multiple fatalities in 17 households, with up to five deaths in a single home (List of Deceased). The incredible intensity of the tornado left unusual sights across town. The damage to Udall’s public school was perhaps the most intense ever photographed. Thick, steal cross-beams arching over the school’s gym were snapped and, in some cases, blown completely away (NWS image). Near one of the classrooms, the severely denuded frame of a Ford truck was left tangled in a partially debarked tree. Areas of grass around the campus were scoured from the ground, and low-lying vegetation was stripped bare (Udall Historical Museum). Farther inside town, power poles were snapped like toothpicks several feet above the ground and a 30ft by 40ft concrete block building was swept away. The Udall event remains by far the deadliest tornado in Kansas history and one of the worst disasters to ever occur within the boundaries of tornado alley.

Vehicles across town were thrown long distances and mangled beyond recognition. At left, the tornado’s most iconic sight was the remains of a truck wrapped around a tree near the public school. A postcard from the time wrote that the (very likely deceased) driver was found a quarter mile outside town. (Images from the Udall Historical Museum)

At left, the foundation of a home that was swept completely away. Nearly every home south of 2nd Street was obliterated in F5 fashion. At right, a grade school with thick brick walls was nearly leveled to the ground. (Images from the Udall Historical Museum)

Composite aerial view of the town taken two days later after only moderate clean-up had occurred. The southern section of town (at left) was swept completely away, leaving a checkerboard of empty foundations. The rest of the community was left as a patchwork of F5 to F0 damage, with the least damage occurring in the northwest corner of town.

At left, ground scouring just east of town. At right, a field near the high school that appears to have been stripped bare (as evidenced by the post-storm tire tracks, which are a common sight in ground effected by F5 winds). The trees in the background have been completely debarked. (Right image from the Udall Historical Museum)

6. Tupelo, Mississippi – April 5, 1936

Catastrophic damage following the 1936 Tupelo tornado.

□ One of the worst tornado disasters in world history occurred in the midst of a wide-scale severe weather outbreak that brought devastating tornadoes throughout the Southeastern United States in the spring of 1936. Just after 8pm on April 5th, a massive funnel touched down approximately eight miles southwest of Tupelo, Mississippi. Little is known about the tornado’s path outside the city, but several fatalities occurred in rural areas, including one person who was killed in a vehicle swept off a road (Mississippi State Geological Survey). As the tornado raced through the outskirts of town it swept away the Burroughs home, leading to the deaths of the couple and their 11 children (New York Times, 1936).

One witness described the storm as “four funnels that merged” just west of town (The Press-Scimitar, 1936). More than a dozen large, well-constructed plantation homes were swept completely away as the tornado entered the wealthy Willis Heights neighborhood (Grazulis, 1993). Reported damage patterns indicate the tornado had a complex multiple vortex structure as some homes adjacent to the worst devastation suffered relatively modest damage (Mississippi State Geological Survey). The tornado tore through residential neighborhoods just north of the city’s business district, with most of the destruction occurring in a 300 yard wide swath centered near the intersection of Madison and Allen Street. One witness recalled that “all of a sudden, all these houses across the street went down like paper” (Edith Gurner, 2008). Residents scrambled into unusual hiding spots as the tornado approached, including one man who survived the storm after crawling into a manhole.

The tornado likely moved in excess of 55mph and took less than two minutes to reach the eastern side of Tupelo. Tens of thousands of pounds of debris were centrifuged around the core of the tornado as it crossed Gum Pond, where dozens of bodies from across town were later recovered. Many of the dead pulled from the water were black victims who likely originated from a working class neighborhood several blocks to the west. Materials from across town piled against the eastern shore of the pond as the tornado exited the area and plowed to the northeast. Heavy timbers and construction beams pierced deeply into the ground and the thick, concrete Battle of Tupelo Monument was blown apart. Additionally, fields east of town were scoured of vegetation and left covered with pulverized debris the size of woodchips (Mississippi State Geological Survey).

After the storm passed, rescue workers and the citizens of Tupelo combed the wreckage as torrential rain fell over the area. One survivor later reported that there was an eerie silence in the worst affected areas, without a single cry or moan coming from the rubble (Moore, 1992). The condition of some of the bodies made determining even the sex of the dead challenging (Mississippi State Geological Survey). Entire families were wiped out in the storm, with multiple households suffering more than five fatalities. The tornado’s final death toll is debatable due to the unknown fate of approximately 100 critically injured white patients and an unknown (but likely similar) number of injured black residents (Grazulis, 1993). The official death toll of 216 only takes into account the immediate fatalities from the storm, so later estimates were increased to 233. A final figure of 250 deaths seems appropriate, making the Tupelo event the deadliest tornado disaster in a single US town (Grazulis, 1993). The fatality rate within the main damage swath was perhaps the highest of any tornado to cause more than 100 deaths since the turn of the 20th century. While the storm was largely forgotten amidst the turmoil of the Great Depression, it remains one of the most catastrophic severe weather events to occur on American soil.

Aerial views of damage in Tupelo. At left, the devastation around Gum Pond. Possible vegetation scouring is visible atop the mound at right center. At right, looking northeast at the tornado’s path through the city.

Views of damage in Tupelo. At left, the remains of homes and a tree that was stripped bare by Gum Pond. At bottom right, only sections of baseboard remain where a home once stood.

At left, complete devastation in the eastern section of town. At right, a heavily damaged mansion that was similar to nearby residences that were reduced to their foundations. The three-story Hoffman house at 365 North Church Street was swept completely away, leading to several fatalities.

At left, the remains of the Hoffman mansion, which was swept down to its baseboards. Homes across the street suffered relatively modest damage. At right, a field that was “stripped bare” just east of town. (Mississippi State Geological Survey, 1936)

5. Hudsonville, Michigan – April 3, 1956

The Hudsonville tornado never took on the “wedge” shape typical of most F5 tornadoes and instead appeared as a large funnel, sometimes with two or more vortices visible at once. (Image by Marvin Bueker)

□ In the spring of 1956, one of the most violent tornadoes ever documented touched down far outside tornado alley in the outskirts of Grand Rapids, Michigan. Thousands of residents across the area witnessed the widely visible funnel as it turned to the north-northeast at nearly 50mph. The first instances of F5 damage occurred only five minutes after touchdown as the tornado crossed New Holland Street. Several newly built homes in the area were swept completely away, leading to the storm’s first fatality. Heavy pieces of furniture from the destroyed residences were thrown several hundred yards at high speeds, leaving long gouge marks in the ground upon impact. Aerial views of ground scouring indicate that the tornado intensified even further as it continued towards the west side of Hudsonville. The storm was well into the F5 category when it crossed the intersection of Van Buren Street and 40th Avenue. Seven homes within a 100-yard wide streak nearly vanished without a trace. The Oostendorp home was swept completely away along with the flooring and plumbing fixtures, leading to the deaths of the homeowner and his infant son (1956tornadoes). Vegetation around the home was scoured from the ground or left clinging by only a few roots, whereas neighboring homes only 60 yards to the east were left damaged but still standing.

The tornado maintained its strength as it crossed Port Sheldon Street near Elmwood Lake. Approximately fifteen homes were considered destroyed in this area. Four fatalities occurred in one home that was swept completely away. The underground basement of the home where the fatalities occurred was swept clean of furniture and personal affects. Debris from obliterated structures was whipped into long lines of wind rowing that extended more than a half mile through the surrounding fields. A car that had been driving on Port Sheldon Street was hurled several hundred feet, killing the two occupants. In total, 13 deaths were reported in the Hudsonville area.

After crossing the Grand River, the tornado swept through rural areas near the town of Standale, where four people died (Sheboygan Journal Wisconsin, 1956). The tornado would continue for another 40 miles through sparsely populated areas north of Grand Rapids. The final fatality occurred near Comstock Park, where several homes were leveled to the ground. Photographs indicate that the tornado narrowed into a long, snake-like funnel in the latter stages of its life before finally dissipating. Overall, the tornado caused 18 deaths and completely obliterated nearly 100 homes.

The remains of a home where a man and his young son were killed. Vegetation around the bare foundation was scoured from the ground and the fallen tree trunk behind the home was debarked and stripped of branches. Much of the furniture and debris from the home was found more than a quarter mile away. Amazingly, the homeowner’s wife and daughter survived the tornado, though both were critically injured. (Image by Thelma Bakker)

Extreme damage to cars near Port Sheldon Street. The mangled car at right originated from a home where four fatalities occurred. (Images by Thelma Bakker)

Aerial view of F5 damage to two homes along 40th Avenue. The tornado’s narrow path was made visible by streaks of pronounced wind rowing, an indication of extreme intensity. Similar wind rowing was photographed throughout the tornado’s damage path. All of the photographs used in this section came from 1956tornadoes flickr page, which is the single best resource for information and imagery on the Hudsonville tornado.