May 3, 1999, Oklahoma Tornado Outbreak

Oklahoma City NEXRAD image at 7:12 pm. The radar shows a classic hook echo at the location of the Bridge Creek/Moore tornado.
Date of tornado outbreak:	May 3-6, 1999
Duration1:	~72 hours
Maximum rated tornado2:	F5 tornado
Tornadoes caused:	66
Damages:	$1.5 billion (2005 USD)
Fatalities:	48
Areas affected:	Oklahoma, Kansas, Texas, Tennessee
1Time from first tornado to last tornado 2Most severe tornado damage; see Fujita Scale Image File history File links Tornado_radar_hook_echo. ... NEXRAD Radar at NSSL NEXRAD or Nexrad (Next-Generation Radar) is a network of 158 high-resolution Doppler radars operated by the National Weather Service, an agency of the National Oceanic and Atmospheric Administration (NOAA), in the United States. ... A classic hook echo. ... May 3 is the 123rd day of the year in the Gregorian calendar (124th in leap years). ... May 6 is the 126th day of the year in the Gregorian calendar (127th in leap years). ... Year 1999 (MCMXCIX) was a common year starting on Friday (link will display full 1999 Gregorian calendar). ... The Fujita scale (F-Scale), or Fujita-Pearson scale, rates a tornados intensity by the damage it inflicts on human-built structures and sometimes on vegetation. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ... ISO 4217 Code USD User(s) the United States, the British Indian Ocean Territory,[1] the British Virgin Islands, Cambodia, East Timor, Ecuador, El Salvador, the Marshall Islands, Micronesia, Palau, Panama, Turks and Caicos Islands, and the insular areas of the United States Inflation 2. ... Official language(s) None Capital Oklahoma City Largest city Oklahoma City Area  Ranked 20th  - Total 69,960 sq mi (181,196 km²)  - Width 230 miles (370 km)  - Length 298 miles (480 km)  - % water 1. ... This article needs additional references or sources to facilitate its verification. ... Official language(s) No Official Language See languages of Texas Capital Austin Largest city Houston Area  Ranked 2nd  - Total 261,797 sq mi (678,051 km²)  - Width 773 miles (1,244 km)  - Length 790 miles (1,270 km)  - % water 2. ... Official language(s) English Capital Nashville Largest city Memphis Largest metro area Nashville Area  Ranked 36th  - Total 42,169 sq mi (109,247 km²)  - Width 120 miles (195 km)  - Length 440 miles (710 km)  - % water 2. ... The Fujita scale (F-Scale), or Fujita-Pearson scale, rates a tornados intensity by the damage it inflicts on human-built structures and sometimes on vegetation. ...

The May 3, 1999, Oklahoma Tornado Outbreak was the first stage of a severe weather event that lasted from May 3 to May 6 and brought violent storms to Oklahoma, Kansas, Arkansas, and Tennessee. This article concentrates on the events in Oklahoma. On May 3, 66 tornadoes broke out in Oklahoma and Kansas. The most significant tornado first touched down southwest of Chickasha, Oklahoma, and became an F5 before dissipating over Midwest City, Oklahoma. The tornado tore through Bridge Creek, Oklahoma, leveling the town. Forty-eight people perished during the outbreak. This tornadic event ranks in severity with the Palm Sunday tornado outbreak of 1965. With a total of 66 tornadoes, it was the most prolific tornado outbreak in Oklahoma history, although not the deadliest. There was a Storm Stories episode about this tornado outbreak. It was also featured as a book bonus in an issue of Readers Digest. Official language(s) None Capital Oklahoma City Largest city Oklahoma City Area  Ranked 20th  - Total 69,960 sq mi (181,196 km²)  - Width 230 miles (370 km)  - Length 298 miles (480 km)  - % water 1. ... This article needs additional references or sources to facilitate its verification. ... Chickasha is a city located in Grady County, Oklahoma. ... Midwest City is a city in Oklahoma County, Oklahoma, United States. ... Bridge Creek is a town in Grady County, Oklahoma. ... 1Time from first tornado to last tornado 2Most severe tornado damage; see Fujita Scale The first Palm Sunday tornado outbreak occurred on April 11, 1965 and involved 78 tornadoes (38 significant, 19 violent, 21 killers) hitting the Midwest. ... To meet Wikipedias quality standards, this article may require cleanup. ... The cover of the May 2004 issue of Readers Digest. ...

Outbreak description

The day started sunny, warm, and humid. The Storm Prediction Center in Norman, Oklahoma initially issued a "slight risk" for severe weather for most of the state of Oklahoma early that morning. By late morning the latest observations and forecasts began to indicate an increasing likelihood of widespread severe weather, and the SPC upgraded sections of the southern plains to "moderate risk." By 3 pm, it had become evident that a widespread severe weather event was imminent. Parts of Oklahoma and Kansas were then further upgraded to "high risk." When a "high risk" is issued, this usually indicates a significant threat for severe thunderstorms and tornadoes including damaging tornadoes. The SPC issued a tornado watch by mid-afternoon as conditions gathered together for what would be a historic tornado outbreak. The CAPE values reached nearly 6,000 J/kg during the day. The Storm Prediction Center, located in Norman, Oklahoma, is part of the National Centers for Environmental Prediction (NCEP), operating under the control of the National Weather Service, which in turn is part of the National Oceanic and Atmospheric Administration (NOAA) of the U.S. government. ... Bizzell Library, University of Oklahoma Norman, Oklahoma, is the county seat and largest city in Cleveland County in the U.S. state of Oklahoma, and is part of the Oklahoma City Metropolitan Statistical Area. ... A tornado watch is issued when weather conditions are favorable for the development of severe thunderstorms that are capable of producing tornados. ... In meteorology, convective available potential energy (CAPE) is the amount of energy a parcel of air would have if lifted a certain distance vertically through the atmosphere. ...

The beautiful May morning gave way to raging dark skies in the afternoon. Large supercell thunderstorms developed and in the late afternoon through the mid-evening hours of that Monday, tornadoes began to break out across the state. Satellite view of a supercell A supercell is a severe thunderstorm with a deep rotating updraft (a mesocyclone) [1]. Supercell thunderstorms are the largest, most severe class of single-cell thunderstorms. ...

(based on NOAA Storm Data)

The Moore F5

Path

A home torn apart by the Moore, Oklahoma F5 tornado

The most significant tornado of the outbreak touched down just southwest of the community of Amber, Oklahoma, and headed northeast, parallel to Interstate 44, just after another tornado had passed over the airport in Chickasha, OK. (Note: it may be argued that the storms touching down in Chickasha and Amber were the same storm; however, for weather tracking purposes, each touchdown is counted as a separate tornado which is most probable.) The storm continued moving northeast, destroying the community of Bridge Creek and crossing I-44 just north of Newcastle. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Moore is a rapidly growing suburb in Cleveland County, Oklahoma and is part of the Oklahoma City Metropolitan Area. ... Amber is a town located in Grady County, Oklahoma. ... Interstate 44 (abbreviated I-44) is an interstate highway in the central United States. ... Bridge Creek is a town in Grady County, Oklahoma. ... Newcastle is a city in McClain County, Oklahoma and is part of the Oklahoma City Metropolitan Area. ...

The tornado then crossed the Canadian River, passing into far southern Oklahoma City. As it passed over Bridge Creek, Oklahoma, around 6:54 pm, a Doppler On Wheels (DOW: Wurman et al. 1997, Wurman 2001) mobile Doppler radar detected winds of 301 +/- 20 mph [1] inside the tornado at a height of 32 m AGL (Wurman et al. 2007). (The old record was a 257-268 mph wind measurement from a Doppler radar near Red Rock, Oklahoma, as reported in a formal publication by Bluestein et al. (1993)). These winds, however, occurred above the ground, and winds at the surface may not have been quite this intense. The tornado continued on into Moore and then passed over the intersection of Shields Boulevard and Interstate 35 and back into Oklahoma City, crossing Interstate 240 near Bryant Avenue. The storm then turned more northerly, striking parts of Del City and Tinker Air Force Base near Sooner Road as an F4 before diminishing over Midwest City and finally lifting near the intersection of Reno Avenue and Woodcrest Drive. The Canadian River is the largest tributary of the Arkansas River. ... Bridge Creek is a town in Grady County, Oklahoma. ... Doppler Effect Doppler radar uses the Doppler effect to measure the radial velocity of targets in the antennas directional beam. ... Red Rock is a town located in Noble County, Oklahoma. ... This Interstate Highway article needs to be cleaned up to conform to both a higher standard of article quality and accepted design standards outlined in the WikiProject U.S. Interstate Highways. ... MAJOR JUNCTIONS JUNCTION EXIT # I-44 Oklahoma 0 I-35 Oklahoma 4 OK-77H (Sooner Rd. ... Del City is a city located in Oklahoma County, Oklahoma and is part of the Oklahoma City Metropolitan Area. ... A water tower on the north side of Tinker Air Force Base Tinker Air Force Base — Oklahoma City Air Logistics Center (OC-ALC)— is a major U.S. Air Force military base located near Oklahoma City, in the suburb of Midwest City, Oklahoma. ...

Casualties

The frame of a pickup truck wrapped around a utility pole from the Moore, Oklahoma F5 tornado

36 people were killed in this tornado. More than 10,500 buildings and 47 businesses were destroyed. This tornado caused $1.1 billion in damage, making it the costliest single tornado in U.S. history. This was the deadliest tornado since the April 10, 1979 Wichita Falls, Texas Tornado which killed 42 people. However, early warning saved many lives. Warnings were issued well in advance of the tornado's arrival, and the Oklahoma City broadcast media interrupted programming to follow the storms on radar and even by helicopter. The death toll would have been much higher if people had not been warned so far in advance. Following the storm, three of the local television stations in Oklahoma City: KOCO-TV, KWTV and KFOR-TV continued coverage of the damaging and deadly tornadoes throughout the day on May 4. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Moore is a rapidly growing suburb in Cleveland County, Oklahoma and is part of the Oklahoma City Metropolitan Area. ... April 10 is the 100th day of the year (101st in leap years) in the Gregorian calendar. ... For the song by the Smashing Pumpkins, see 1979 (song). ... The Wichita Falls Tornado is the tornado event that occurred on April 10, 1979. ... Nickname: Location in Oklahoma County and the state of Oklahoma. ... A helicopter is an aircraft which is lifted and propelled by one or more horizontal rotors consisting of two or more rotor blades. ... KOCO-TV, commonly referred to as KOCO 5 or Eyewitness News 5 is the ABC affiliate in the Oklahoma City television market. ... KWTV, commonly referred to as NEWS9 is the CBS affiliate in Oklahoma City, Oklahoma. ... KFOR-TV, referred to on-air as Oklahomas NewsChannel4 is the NBC affiliate based out of Oklahoma City, Oklahoma. ... May 4 is the 124th day of the year (125th in leap years) in the Gregorian calendar. ...

Impact

This article needs additional references or sources to facilitate its verification. ... Sedgwick County (standard abbreviation: SG) is a county located in the U.S. state of Kansas. ... Official language(s) None Capital Oklahoma City Largest city Oklahoma City Area  Ranked 20th  - Total 69,960 sq mi (181,196 km²)  - Width 230 miles (370 km)  - Length 298 miles (480 km)  - % water 1. ... Cleveland County is a county in the state of Oklahoma. ... Grady County is a county located in the U.S. state of Oklahoma. ... Kingfisher County is a county located in the state of Oklahoma. ... Logan County is a county located in the state of Oklahoma. ... McClain County is a county located in the state of Oklahoma. ... Payne County is a county located in the state of Oklahoma. ... Pottawatomie County is a county located in the state of Oklahoma. ... Oklahoma County is a county located in the state of Oklahoma. ... Official language(s) English Capital Nashville Largest city Memphis Largest metro area Nashville Area  Ranked 36th  - Total 42,169 sq mi (109,247 km²)  - Width 120 miles (195 km)  - Length 440 miles (710 km)  - % water 2. ... Perry County is a county located in the state of Tennessee. ... Official language(s) No Official Language See languages of Texas Capital Austin Largest city Houston Area  Ranked 2nd  - Total 261,797 sq mi (678,051 km²)  - Width 773 miles (1,244 km)  - Length 790 miles (1,270 km)  - % water 2. ... Titus County is a county located in the state of Texas. ...

The risk of using overpasses as storm shelters

Three of the deaths reported in the tornado were from people who took shelter underneath overpasses in the area of the path of the Moore-Bridge Creek F5 tornado. The deaths occurred at the 16th Street overpass over Interstate 44 in Newcastle (just east of Bridge Creek), at the Shields Boulevard overpass over Interstate 35 in Moore, and the overpass at mile marker 176.5 on Interstate 35 in rural northwestern Payne County (west of Stillwater).

The two overpass deaths associated with the Oklahoma City storm occurred when the tornado was at its most violent (i.e. F4 or F5) intensity. However, it is of note that the tornado that caused the fatality at Interstate 35 mile marker 176.5 in Payne County was of F2 intensity when it struck the overpass and was NOT in an urban area. This suggests, contrary to the Kansas Turnpike video (see the El Dorado Lake Tornado), that a tornado need not be a large, violent tornado with a considerable debris cloud to cause fatal injuries to people seeking shelter from storms under overpasses. In addition to the fatal injuries to three people, there were also many severe, potentially life-threatening and gruesome injuries inflicted upon people underneath the overpasses that in some cases has left these people with permanent disabilities. To meet Wikipedias quality standards, this article or section may require cleanup. ...

Fujita scale

This tornado's remarkable wind speed, at the high extreme of the Fujita Scale's F5, led to much speculation that the scale would be modified to include an F6 category, due to the winds possibly exceeding 320 mph. This speculation ignored the fact that the Fujita scale measures damage rather than windspeed, since the scale was developed prior to the introduction of Doppler radar. Windspeed estimates associated with the different categories represent the speeds scientists believe are required to produce that damage rather than the windspeed in that particular storm. The damage caused by an F5-designated tornado leaves very little room for a higher category. The Fujita scale (F-Scale), or Fujita-Pearson scale, rates a tornados intensity by the damage it inflicts on human-built structures and sometimes on vegetation. ...

The tornado was the last official F5 to hit the United States with the old Fujita scale rating. The next category 5 tornado occurred on May 4, 2007 in Greensburg, Kansas during the May 2007 Tornado Outbreak and killed 9 people. Since February 1, 2007 the National Weather Service used the Enhanced Fujita Scale to rate tornadoes and the Greensburg tornado was recorded as the first EF5 tornado ever and almost exactly 8 years after the Bridge Creek-Moore event. Greensburg is a city in the central part of Kiowa County, located in Southwest Kansas, in the Central United States. ... 1Time from first tornado to last tornado 2Most severe tornado damage; see Enhanced Fujita Scale The May 2007 Tornado Outbreak was an extended tornado outbreak that started on May 4, 2007, affecting portions of the Central United States. ... The National Weather Service (NWS) is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration (NOAA) of the United States government. ... The Enhanced Fujita Scale, or EF Scale, is the scale for rating the strength of tornadoes in the United States estimated via the damage they cause. ...

Other significant tornadoes

In addition to the devastating F5 tornado that hit the southern suburbs of Oklahoma City, there were numerous other significant tornadoes in the outbreak. An F3 tornado hit the town of Stroud, in-between Oklahoma City and Tulsa on Interstate 44, destroying the Tanger Outlet Mall. The mall has not been rebuilt. May 3 is the 123rd day of the year in the Gregorian calendar (124th in leap years). ... Year 1999 (MCMXCIX) was a common year starting on Friday (link will display full 1999 Gregorian calendar). ... The Wichita Falls Tornado is the tornado event that occurred on April 10, 1979. ... April 10 is the 100th day of the year (101st in leap years) in the Gregorian calendar. ... For the song by the Smashing Pumpkins, see 1979 (song). ... On May 6, 1975, an F4 tornado touched down at 4:24 PM in Sarpy County, Nebraska and then moved north-east, cutting into Douglas County and through the city of Omaha. ... May 6 is the 126th day of the year in the Gregorian calendar (127th in leap years). ... 1975 (MCMLXXV) was a common year starting on Wednesday. ... The Lubbock Tornado was an F5 tornado that occurred in Lubbock, Texas on May 11, 1970. ... May 11 is the 131st day of the year in the Gregorian calendar (132nd in leap years). ... 1970 (MCMLXX) was a common year starting on Thursday. ... The Topeka Tornado of 1966 was one of the worst tornadoes in Kansas history. ... June 8 is the 159th day of the year in the Gregorian calendar (160th in leap years), with 206 days remaining. ... 1966 (MCMLXVI) was a common year starting on Saturday (the link is to a full 1966 calendar). ... The Windsor Locks, Connecticut tornado struck on October 3, 1979. ... October 3 is the 276th day of the year (277th in leap years) in the Gregorian calendar. ... For the song by the Smashing Pumpkins, see 1979 (song). ... 1Time from first tornado to last tornado 2Most severe tornado damage; see Fujita Scale The St. ... May 27 is the 147th day of the year (148th in leap years) in the Gregorian calendar. ... Year 1896 (MDCCCXCVI) was a leap year starting on Wednesday (link will display calendar). ... 1Time from first tornado to last tornado 2Most severe tornado damage; see Fujita Scale The Super Outbreak is the largest tornado outbreak on record. ... April 3 is the 93rd day of the year (94th in leap years) in the Gregorian calendar, with 272 days remaining. ... 1974 (MCMLXXIV) was a common year starting on Tuesday. ... March 31 is the 90th day of the year in the Gregorian calendar (91st in leap years), with 275 days remaining. ... 1973 (MCMLXXIII) was a common year starting on Monday. ... The Flint-Worcester Tornadoes were two tornadoes, one occurring in Flint, Michigan on June 8, 1953, the other in Worcester, Massachusetts on June 9, 1953. ... June 9 is the 160th day of the year in the Gregorian calendar (161st in leap years), with 205 days remaining. ... 1953 (MCMLIII) was a common year starting on Thursday. ... ISO 4217 Code USD User(s) the United States, the British Indian Ocean Territory,[1] the British Virgin Islands, Cambodia, East Timor, Ecuador, El Salvador, the Marshall Islands, Micronesia, Palau, Panama, Turks and Caicos Islands, and the insular areas of the United States Inflation 2. ...

Another F4 hit the town of Mulhall, north of Guthrie, destroying most of the town and even toppling the city's water tower. This wedge tornado was very wide, at times exceeding well over a mile wide. According to stormchaser Roger Edwards, it may have been as violent if not even more than the F5 Moore/Bridge Creek tornado [2]. A Doppler On Wheels (DOW) mobile radar observed this tornado as it crossed Mulhall. The DOW documented the largest ever observed core flow circulation with a distance of 1600 m between peak velocities on either side of the tornado, and a roughly 7km width of peak wind gusts exceeding 43 m/s, making the Mulhall tornado the largest tornado ever measured quantitatively (Wurman et al. 2007). The DOW measured a complex multiple-vortex structure and(Wurman 2002) with several multiple vortices containing winds of up to 115 m/s rotating around the tornado. The 3D structure of the tornado has been analyzed in Lee and Wurman 2005.

One of the final tornadoes in the outbreak almost hit the studios of ABC affiliate KTUL-TV in Tulsa, located on Lookout Mountain, a few miles west of the city itself, in the early morning hours of May 4 around 12:15am CDT. Then Chief Meteorologist Travis Meyer advised his co-workers to take shelter while still on the air reporting on the approaching tornado. It weakened before reaching the station. The American Broadcasting Company ( oftenly known as ABC) operates television and radio networks in the United States and is also shown on basic cable in Canada. ... KTUL, referred to on air as NewsChannel 8, is the ABC affiliate in Tulsa, Oklahoma. ... Nickname: Location in the state of Oklahoma Coordinates: Country United States State Oklahoma Counties Tulsa, Osage, Wagoner, Rogers Government  - Mayor Kathy Taylor (D) Area  - City  186. ... May 4 is the 124th day of the year (125th in leap years) in the Gregorian calendar. ...

The May 3 tornado event was actually part of a 3-day event that included tornadoes in Kansas and Texas. A deadly tornado killed six people in Haysville and Wichita, Kansas, the same day. The event killed 1 person in Texas on Tuesday, May 4 and then killed four in Tennessee on Wednesday and Thursday. May 3 is the 123rd day of the year in the Gregorian calendar (124th in leap years). ... This article needs additional references or sources to facilitate its verification. ... Official language(s) No Official Language See languages of Texas Capital Austin Largest city Houston Area  Ranked 2nd  - Total 261,797 sq mi (678,051 km²)  - Width 773 miles (1,244 km)  - Length 790 miles (1,270 km)  - % water 2. ... Haysville is a city in Sedgwick County, Kansas, United States. ... Nickname: The Air Capital, The Peerless City Location in the state of Kansas County Sedgwick Government  - Mayor Carlos Mayans Area  - City 359. ... This article needs additional references or sources to facilitate its verification. ... May 4 is the 124th day of the year (125th in leap years) in the Gregorian calendar. ... Official language(s) English Capital Nashville Largest city Memphis Largest metro area Nashville Area  Ranked 36th  - Total 42,169 sq mi (109,247 km²)  - Width 120 miles (195 km)  - Length 440 miles (710 km)  - % water 2. ...

Damage estimates

The remains of a disintegrated mobile home in Grady County, Oklahoma from the Moore, Oklahoma F5 tornado

Note: The following was adapted from public domain, official National Weather Service web sites. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Grady County is a county located in the U.S. state of Oklahoma. ... Moore is a rapidly growing suburb in Cleveland County, Oklahoma and is part of the Oklahoma City Metropolitan Area. ...

The following is a list of the number of homes and businesses damaged by the tornadoes in the outbreak:

• Includes 53 stores at the Tanger Outlet Center in Stroud.

Source: National Weather Service Norman, OK Forecast Office--

See also

• List of tornadoes and tornado outbreaks
• Climate of Oklahoma City

// Tornado Events These are some notable tornadoes, tornado outbreaks, and tornado outbreak sequences that have occurred around the globe. ... The climate of Oklahoma City is mild through most of the year. ...

External links and references

• The Tornado History Project May 3, 1999 tornado activity overlaid on a Google Map
• www.srh.noaa.gov/oun/
• The 3 May 1999 Oklahoma Tornadoes (David Schultz, CIMMS)