View source for 1999 Oklahoma tornado outbreak

{{short description|Tornado outbreak in May 1999}}
{{Use American English|date=May 2025}}
{{Use mdy dates|date=February 2025}}
{{Infobox weather event
| image = {{multiple image
| border = infobox 
| perrow = 1/2
| total_width = 300
| image1 = Tornado1999AnimLrg.gif
| image2 = 1999 Bridge Creek-Moore tornado radar KTLX 1999-05-03 2351Z.gif
| image3 = A tornado near Anadarko, Oklahoma, on May 3, 1999.jpg
| image4 = 1999-05-03 bigoutbreak.png
}}
| alt =
| caption = '''Clockwise from top:''' Satellite image of [[supercell]]s developing across central [[Oklahoma]] late on May 3; a tornado near [[Anadarko, Oklahoma]]; tracks of all the tornadoes spawned by the outbreak in Oklahoma; radar reflectivity image of [[1999 Bridge Creek–Moore tornado|the F5 tornado]] that impacted Bridge Creek and Moore
| duration = May 2–8, 1999
}}{{Infobox weather event/Tornado outbreak
| tornadoes = [[List of tornadoes in the 1999 Oklahoma tornado outbreak|152]]
| fujita-scale = F5
| duration = 6 days, 1 hour and 35 minutes 
| winds = '''Tornadic''' – {{convert|321|mph|km/h|abbr=on}}<br><small>([[Oklahoma City|Southwest Oklahoma City, OK]] F5 tornado on May&nbsp;3)</small> <ref name=":2">{{Cite web 
|date=23 June 2024 |title=Flexible Array of Radars and Mesonets (FARM) statement concerning preliminary peak wind speed determinations based on Doppler On Wheels (DOW) data obtained in the Greenfield, Iowa tornado of 21 May 2024 section more detail|url=http://www.farmfacility.org/pdf/best-greenfield-windspeed-note-2024-0623bp2.pdf |website=Flexible Array of Radars and Mesonets facility}}</ref><ref name="Doppler On Wheels">{{cite web|url=http://cswr.org/dow/DOW.htm |title=Doppler On Wheels |date=3 May 1999 |access-date=13 June 2013 |url-status=dead |archive-url=https://web.archive.org/web/20070205124033/http://www.cswr.org/dow/dow.htm |archive-date=5 February 2007 }}</ref>
| gusts = '''Non-tornadic''' – {{convert|115|mph|km/h|abbr=on}} <small>([[Claxton, Anderson County, Tennessee|Claxton, TN]] non-tornadic on May&nbsp;7)</small><ref>{{cite web|work=National Climatic Data Center|publisher=National Oceanic and Atmospheric Administration|year=2013|access-date=June 9, 2013|title=Tennessee Event Report: Thunderstorm Wind|url=http://www.ncdc.noaa.gov/stormevents/eventdetails.jsp?id=5694432 }}</ref>
| largest hail =  {{convert|4.5|in|cm|abbr=on}} in diameter <small>(multiple locations on May&nbsp;3)</small><ref>{{cite web|work=National Climatic Data Center|publisher=National Oceanic and Atmospheric Administration|year=2013|access-date=June 9, 2013|title=Storm Events Database: May 2–8, 1999 Hail 4.00 in and Larger|url=http://www.ncdc.noaa.gov/stormevents/listevents.jsp?hailfilter=4.00&sort=DT&statefips=-999%2CALL&county=ALL&zone=ALL&eventType=%28C%29+Hail&beginDate_yyyy=1999&beginDate_mm=05&beginDate_dd=02&endDate_yyyy=1999&endDate_mm=05&endDate_dd=08|archive-url=https://web.archive.org/web/20160304063156/http://www.ncdc.noaa.gov/stormevents/listevents.jsp?hailfilter=4.00&sort=DT&statefips=-999,ALL&county=ALL&zone=ALL&eventType=(C)+Hail&beginDate_yyyy=1999&beginDate_mm=05&beginDate_dd=02&endDate_yyyy=1999&endDate_mm=05&endDate_dd=08|archive-date=March 4, 2016|url-status=dead}}</ref> 
| fujita-ref = 
}}{{Infobox weather event/Effects
| outages =
| fatalities = 50 fatalities (+7 non-tornadic)
| injuries = 895
| missing =
| damages = $1.5 billion (1999 USD)<ref>{{cite web|work=National Climatic Data Center|publisher=National Oceanic and Atmospheric Administration|year=2013|access-date=June 9, 2013|title=Storm Events Database: May 2–7, 1999 Tornadoes|url=http://www.ncdc.noaa.gov/stormevents/listevents.jsp?beginDate_mm=05&beginDate_dd=02&beginDate_yyyy=1999&endDate_mm=05&endDate_dd=07&endDate_yyyy=1999&eventType=%28C%29+Tornado&submitbutton=Search&statefips=-999%2CALL|archive-url=https://web.archive.org/web/20160304051634/http://www.ncdc.noaa.gov/stormevents/listevents.jsp?beginDate_mm=05&beginDate_dd=02&beginDate_yyyy=1999&endDate_mm=05&endDate_dd=07&endDate_yyyy=1999&eventType=(C)+Tornado&submitbutton=Search&statefips=-999,ALL|archive-date=2016-03-04|url-status=dead}}</ref>
| affected = [[Midwestern United States|Midwestern]], [[Southern United States]], [[Great Plains]]
}}{{Infobox weather event/Footer
| season = [[Tornadoes of 1999|Tornado outbreaks of 1999]]
}}

The '''1999 Oklahoma tornado outbreak''' was a large, historic,<ref name="GrazulisBook"/> and devastating [[tornado outbreak]] that took place across much of the [[Central United States]], with most tornadoes occurring from May 2–5, 1999; scattered activity occurred afterwards until May 8 in parts of the [[Eastern United States]], as well as southern [[Canada]]. During this week-long event, 152&nbsp;tornadoes touched down in these areas. The most dramatic events unfolded during the afternoon of May&nbsp;3 through the early morning hours of May&nbsp;4 when more than half of these storms occurred. [[Oklahoma]] experienced its largest tornado outbreak on record from this event, with 70&nbsp;confirmed. The most notable of these was the [[Fujita scale|F5]] [[1999 Bridge Creek–Moore tornado|Bridge Creek–Moore tornado]] which devastated Oklahoma City and suburban communities. The tornado killed 36&nbsp;people and injured 583&nbsp;others; losses amounted to $1&nbsp;billion, making it the first billion-dollar tornado in history.<ref>{{cite web|work=National Weather Service Office in Norman, Oklahoma|publisher=National Oceanic and Atmospheric Administration|date=June 22, 2011|access-date=June 4, 2013|title=The Great Plains Tornado Outbreak of May 3–4, 1999|url=http://www.srh.noaa.gov/oun/?n=events-19990503}}</ref> Overall, 50&nbsp;people lost their lives during the outbreak and damage amounted to $1.4&nbsp;billion.<ref>{{cite web|work=National Climatic Data Center|publisher=National Oceanic and Atmospheric Administration|year=2013|access-date=June 6, 2013|title=Storm Events Database: May 2–7, 1999 Tornadoes|url=http://www.ncdc.noaa.gov/stormevents/listevents.jsp?beginDate_mm=05&beginDate_dd=02&beginDate_yyyy=1999&endDate_mm=05&endDate_dd=07&endDate_yyyy=1999&eventType=%28C%29+Tornado&submitbutton=Search&statefips=-999%2CALL|url-status=dead|archive-url=https://web.archive.org/web/20160304051634/http://www.ncdc.noaa.gov/stormevents/listevents.jsp?beginDate_mm=05&beginDate_dd=02&beginDate_yyyy=1999&endDate_mm=05&endDate_dd=07&endDate_yyyy=1999&eventType=(C)+Tornado&submitbutton=Search&statefips=-999,ALL|archive-date=March 4, 2016}}</ref>

On May&nbsp;2, a strong [[Low-pressure area|area of low pressure]] moved out of the [[Rocky Mountains]] and into the [[High Plains (United States)|High Plains]], producing scattered [[severe weather]] and ten tornadoes in [[Nebraska]]. The following day, atmospheric conditions across Oklahoma became significantly more favorable for an outbreak of severe weather. Wind profiles across the region strongly favored tornadic activity, with the [[Storm Prediction Center]] stating, "it became more obvious something major was looming" by the afternoon.<ref name="OutbreakSum"/> Numerous [[supercell thunderstorms]] developed across the state as well as bordering areas in [[Kansas]] and [[Texas]]. Over the following 48&nbsp;hours, May&nbsp;3–4, 116&nbsp;tornadoes touched down across the Central [[United States]]. Following the extensive outbreak, activity became increasingly scattered from May&nbsp;5 to 8, with 26&nbsp;tornadoes touching down across the Eastern United States and [[Quebec]].<ref name="OutbreakSum">{{cite web|work=National Weather Service Office in Norman, Oklahoma|publisher=National Oceanic and Atmospheric Administration|date=May 3, 2010|access-date=June 4, 2013|title=Meteorological Summary of the Great Plains Tornado Outbreak of May 3–4, 1999|url=http://www.srh.noaa.gov/oun/?n=events-19990503-summary}}</ref>

In 2023, tornado expert [[Thomas P. Grazulis]] published the [[outbreak intensity score]] (OIS) as a way to rank outbreaks.<ref name="GrazulisBook">{{cite book |last1=Grazulis |first1=Thomas P. |author1-link=Thomas P. Grazulis |title=Significant Tornadoes 1974–2022 |date=2023 |publisher=The Tornado Project |location=[[St. Johnsbury, Vermont]] |isbn=978-1-879362-01-7 |page=637}}</ref> The outbreak received 145 OIS points, ranking it as a [[List of tornado outbreaks by outbreak intensity score#Historic outbreaks|historic tornado outbreak]].<ref name="GrazulisBook"/>

==Meteorological synopsis==
[[File:Meteorological setup of the 1999 Oklahoma tornado outbreak.gif|left|thumb|250px|A map of the meteorological setup of the 1999 Oklahoma tornado outbreak. The map displays surface and upper level atmospheric features associated with the outbreak.]]
The outbreak was caused by a vigorous upper-level [[trough (meteorology)|trough]] that moved into the [[Great Plains|Central and Southern Plains]] states on the morning of May&nbsp;3. That morning, low stratus clouds overspread much of Oklahoma, with clear skies along and west of a [[dry line]] located from [[Gage, Oklahoma|Gage]] to [[Childress, Texas]]. Air temperatures at 7:00&nbsp;a.m. [[Central Time Zone|Central Daylight Time]] ranged in the mid to upper 60s °F (upper 10s to near 20&nbsp;°C) across the region, while [[dew point]] values ranged in the low to mid 60s °F (mid to upper 10s °C).<ref>[http://www.weather.gov/oun/events-19990503-summary Meteorological Summary of the Great Plains Tornado Outbreak of May 3-4, 1999]</ref> The [[Storm Prediction Center]] (SPC) in [[Norman, Oklahoma]], a division of the [[National Weather Service]], initially issued a slight risk of severe thunderstorms early that morning stretching from the Kansas-Nebraska border to parts of southern Texas, with an intended threat of large hail, damaging winds and tornadoes.<ref>{{cite web|url=http://www.spc.noaa.gov/publications/edwards/3mf5b.gif|title=Severe Weather Outlook at 6:30 a.m. CDT on May 3, 1999}}</ref>

[[File:Radar May 3, 1999 KTLX (small).gif|thumb|250px|Depicts radar imagery ([[Weather radar#Reflectivity|reflectivity]]) taken by the National Weather Service NEXRAD radar, KTLX, in Central Oklahoma during the May 1999 tornado outbreak. This imagery is from May&nbsp;3. ([[Media:Radar May 3, 1999 KTLX.gif|Click for high-quality.]])]]
By late morning, the low cloud cover began to dissipate in advance of the dry line, but during the afternoon high cirrus clouds overspread the region, resulting in filtered sunshine in some areas that caused [[atmospheric instability|atmospheric destabilization]]. The sunshine and heating, combined with abundant low-level moisture, combined to produce a very unstable air mass. Upper air balloon soundings observed strong directional [[wind shear]], cooling temperatures at high atmospheric levels, and the increased potential of [[Convective available potential energy|CAPE]] values potentially exceeding 4000 J/kg, levels that are considered favorable for [[supercell]]s and tornadoes.

As observations and forecasts began to indicate an increasing likelihood of widespread severe weather conditions even more favorable for strong tornadoes, the SPC issued a moderate risk of severe weather at 11:15&nbsp;a.m. CDT for portions of Kansas, Oklahoma and Texas along and near the [[Interstate 40]] corridor.<ref name="spc.noaa.gov">{{cite web|url=http://www.spc.noaa.gov/publications/edwards/3mf5c.gif|title=Severe Weather Outlook at 11:15 a.m. CDT on May 3, 1999}}</ref> By 3:00&nbsp;p.m. CDT, it had become evident that a widespread severe weather event was imminent; the Storm Prediction Center upgraded locations within the moderate risk area to a high risk of severe weather around 4:00&nbsp;p.m. CDT as wind shear profiles, combined with volatile atmospheric conditions, had made conditions highly conducive for a significant tornadic event across most of Oklahoma, southern Kansas and north Texas, including the likelihood of violent, damaging tornadoes.<ref name="spc.noaa.gov"/> The SPC issued a [[tornado watch]] by mid-afternoon as conditions gathered together for what would be a historic tornado outbreak. By the time thunderstorms began developing in the late afternoon, CAPE values over the region had reached to near 6,000 J/kg. 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.

==Confirmed tornadoes==
{{Main|List of tornadoes in the 1999 Oklahoma tornado outbreak}}
{{Tornado Chart | Total=152 | F0=73 | F1=44 | F2=20 | F3=10 | F4=4 | F5=1 }}

===Bridge Creek–Moore, Oklahoma===
{{Main|1999 Bridge Creek–Moore tornado}}
{{Infobox weather event
| name = Bridge Creek–Moore, Oklahoma
| image = OKCTornado1.jpg
| caption              = A view of the damage by the tornado.
| formed               = May 3, 1999, 6:23&nbsp;p.m. [[Central Time Zone|CDT]] ([[UTC−05:00]])
| duration             = 1 hour, 25 minutes
| dissipated           = May 3, 1999, 7:48&nbsp;pm. CDT (UTC−05:00)}}{{Infobox weather event/Tornado
| basin                = atl
| winds                = {{convert|321|mph|km/h|abbr=on|sigfig=3}}<br />{{small|(as measured by mobile [[Doppler weather radar|Doppler&nbsp;radar]])}}<ref name=":2"/><ref name="2024RadarPaper">{{cite journal |last1=Lyza |first1=Anthony W. |last2=Flournoy |first2=Matthew D. |last3=Alford |first3=A. Addison |title=Comparison of Tornado Damage Characteristics to Low-Altitude WSR-88D Radar Observations and Implications for Tornado Intensity Estimation |journal=[[Monthly Weather Review]] |date=19 March 2024 |volume=-1 |issue=aop |doi=10.1175/MWR-D-23-0242.1 |url=https://journals.ametsoc.org/view/journals/mwre/aop/MWR-D-23-0242.1/MWR-D-23-0242.1.xml |access-date=19 March 2024 |publisher=[[National Oceanic and Atmospheric Administration]] and [[University of Oklahoma]] via the [[American Meteorological Society]]}}</ref>
| fujita-scale         = F5
}}{{Infobox weather event/Effects
| year                 = 1999 
| deaths               = 36 (+5 indirect){{citation needed|date=May 2024}}
| injuries             = 583
| damages              = $1&nbsp;billion (1999 [[United States dollar|USD]])<br />${{formatnum:{{Inflation|US|1|1999|r=1}}}} billion ({{inflation/year|US}} USD)
}}{{Infobox weather event/Footer
| season = 
}}

At approximately 3:30&nbsp;p.m. CDT, a severe thunderstorm began forming in [[Tillman County, Oklahoma|Tillman County]] in southwestern Oklahoma; a [[severe thunderstorm warning]] was issued for this storm by the [[National Weather Service Norman, Oklahoma|National Weather Service Weather Forecast Office in Norman]] at 4:15&nbsp;p.m. CDT. The storm quickly developed supercell characteristics and began exhibiting potentially tornadic rotation, resulting in the National Weather Service issuing the first [[tornado warning]] of the event for [[Comanche County, Oklahoma|Comanche]], [[Caddo County, Oklahoma|Caddo]], and [[Grady County, Oklahoma|Grady counties]] approximately 35 minutes later at 4:50&nbsp;p.m. CDT.

The first tornado from this supercell touched down {{convert|7|mi|km}} east-northeast of [[Medicine Park, Oklahoma|Medicine Park]] at 4:51&nbsp;p.m. CDT; it produced four additional tornadoes as it tracked northeast into [[Caddo County, Oklahoma|Caddo County]], the strongest of which (rated as an F3) touched down {{convert|2|mi|km}} west-southwest of [[Laverty, Oklahoma|Laverty]] and dissipated {{convert|2.5|mi|km}} west-northwest of downtown [[Chickasha, Oklahoma|Chickasha]]. This large tornado had exhibited a companion [[satellite tornado]] for a few minutes.<ref>{{cite journal |last = Wurman |first = Joshua |author-link = Joshua Wurman |author2=K. Kosiba |title = Finescale Radar Observations of Tornado and Mesocyclone Structures |journal = Weather Forecast. |volume = 28 |issue = 5 |pages = 1157–74 |date = 2013 |doi = 10.1175/WAF-D-12-00127.1 |bibcode = 2013WtFor..28.1157W |doi-access = free }}</ref>

The storm produced the most significant tornado of the outbreak, which touched down just southwest of the Grady County community of [[Amber, Oklahoma|Amber]] at 6:23&nbsp;p.m. CDT and headed northeast, parallel to [[Interstate 44 (Oklahoma)|Interstate&nbsp;44]], just after another tornado had passed over the airport in [[Chickasha, Oklahoma|Chickasha]]. The storm continued moving northeast, destroying the community of [[Bridge Creek, Oklahoma|Bridge Creek]] and crossing I-44 just north of [[Newcastle, Oklahoma|Newcastle]]. The tornado then crossed the [[Canadian River]], passing into far southern Oklahoma City. As it passed over [[Bridge Creek, Oklahoma|Bridge Creek]], around 6:54&nbsp;p.m., a [[Doppler On Wheels]] mobile Doppler [[weather radar]] detected [[wind speed]]s of {{convert|302|mph|km/h|abbr=on}} – later revised to {{convert|321|mph|km/h|abbr=on}} – inside the tornado at an elevation of {{convert|105|ft|m|abbr=on}}.<ref name=":2"/><ref>{{cite web|publisher=Center for Severe Weather Research |year=2010 |access-date=October 1, 2010 |title=Doppler On Wheels |url=http://cswr.org/dow/DOW.htm |url-status=dead |archive-url=https://web.archive.org/web/20070205124033/http://www.cswr.org/dow/dow.htm |archive-date=February 5, 2007 }}</ref> 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, then passed over the intersection of Shields Boulevard and [[Interstate 35 (Oklahoma)|Interstate&nbsp;35]] and back into [[Oklahoma City, Oklahoma|Oklahoma City]], crossing [[Interstate 240 (Oklahoma)|Interstate 240]] near Bryant Avenue. The storm then turned more northerly, striking parts of [[Del City, Oklahoma|Del City]] and [[Tinker Air Force Base]] near Sooner Road as an F4. The storm damaged and/or destroyed several businesses, homes and churches in Midwest City. Some damage in this area was rated as high-end F4, although F5 was considered. The tornado diminished over Midwest City and finally lifted near the intersection of Reno Avenue and Woodcrest Drive.

Thirty-six people died in this tornado,<ref>{{cite web|url=http://www.weather.gov/oun/events-19990503-storma|title=The Great Plains Tornado Outbreak of May 3-4, 1999 - Storm A Information|author=((US Department of Commerce, NOAA, National Weather Service))|website=www.weather.gov|access-date=2017-02-28|archive-date=2017-02-11|archive-url=https://web.archive.org/web/20170211155104/http://www.weather.gov/oun/events-19990503-storma|url-status=dead}}</ref> and over 8,000 homes were badly damaged or destroyed. The tornado caused $1 billion in damage, making it the second-costliest tornado in U.S. history,<ref>However, adjustment for growth in wealth shows the May 27, 1896 Saint Louis–East Saint Louis tornado to be the costliest on record. See {{cite journal |last=Brooks |first=Harold E. |author2=Doswell III|author3=Charles A. |year=2001 |title=Normalized Damage from Major Tornadoes in the United States: 1890–1999 |journal=Weather and Forecasting |volume=16 |issue=1 |pages=168–176 |doi=10.1175/1520-0434(2001)016<0168:NDFMTI>2.0.CO;2 |url=https://zenodo.org/record/1234647|issn=1520-0434 |bibcode = 2001WtFor..16..168B |doi-access=free }}</ref> and the most costly in history from 1999 to 2011, at which point it was surpassed by the [[2011 Tuscaloosa–Birmingham tornado]] and again by the [[2011 Joplin tornado]]. It was also the deadliest tornado to hit the U.S. since the April 10, 1979 [[1979 Red River Valley tornado outbreak#Wichita Falls, Texas|F4 tornado]] that hit [[Wichita Falls, Texas]], which killed 42 people.<ref>{{cite journal |last=Brooks |first=Harold E. |author2=Doswell III|author3=Charles A. |year=2002 |title=Deaths in the 3 May 1999 Oklahoma City Tornado from a Historical Perspective |journal=Weather and Forecasting |volume=17 |issue=3 |pages=354–361 |doi=10.1175/1520-0434(2002)017<0354:DITMOC>2.0.CO;2 |url=https://zenodo.org/record/1234651|issn=1520-0434 |bibcode = 2002WtFor..17..354B |s2cid=173001 |doi-access=free }}</ref>
{{clear}}

===Cimarron City–Mulhall–Perry, Oklahoma===
{{Infobox weather event
| name = Cimarron City–Mulhall–Perry, Oklahoma
| image = 
| caption              = 
| formed               = May 3, 1999, 9:25&nbsp;p.m. [[Central Time Zone|CDT]] ([[UTC−05:00]])
| duration             = 1 hour, 20 minutes
| dissipated           = May 3, 1999, 10:45&nbsp;p.m. CDT (UTC−05:00)}}{{Infobox weather event/Tornado
| basin                = atl
| winds                = {{convert|257|mph|km/h|abbr=on|sigfig=3}}<br />{{small|(as measured by mobile [[Doppler weather radar|Doppler&nbsp;radar]])}}
| fujita-scale         = F4
}}{{Infobox weather event/Effects
| year                 = 1999 
| deaths               = 2
| injuries             = 26
| damages              = $100&nbsp;million (1999 [[United States dollar|USD]])<br />${{formatnum:{{Inflation|US|100|1999|r=1}}}} million ({{inflation/year|US}} USD)
}}{{Infobox weather event/Footer
| season = 
}}

Late in the evening on May&nbsp;3 at 9:25&nbsp;p.m. CDT, this destructive tornado touched down {{convert|3|mi|km}} southwest of [[Cimarron City, Oklahoma|Cimarron City]] in [[Logan County, Oklahoma]], eventually hitting the town of [[Mulhall, Oklahoma|Mulhall]], located north of [[Guthrie, Oklahoma|Guthrie]].<ref name=":0">{{Cite web |last=US Department of Commerce |first=NOAA |title=The Great Plains Tornado Outbreak of May 3-4, 1999 |url=https://www.weather.gov/oun/events-19990503 |access-date=2023-04-15 |website=www.weather.gov |language=EN-US}}</ref> This [[wedge tornado]], which tracked a {{convert|39|mi|km|adj=on}} path, was very wide and at times exceeded {{convert|1|mi|km|spell=in}} in width. According to [[storm chasing]] meteorologist [[Roger Edwards (meteorologist)|Roger Edwards]], it may have been as violent or more than the F5 Bridge Creek–Moore tornado (however, it was officially rated as an F4).<ref>{{cite web|url=http://www.stormeyes.org/tornado/3may99/|title=Central Oklahoma Tornado Intercept: 3 May 1999 (Roger Edwards)|website=www.stormeyes.org}}</ref>

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 {{convert|abbr=on|1600|m}} between peak velocities on either side of the tornado, and a roughly {{convert|abbr=on|7|km}} width of peak wind gusts exceeding {{convert|abbr=on|43|m/s|mph}}, making the Mulhall tornado the largest tornado ever measured quantitatively.<ref name="urban">{{cite journal |last=Wurman |first=Joshua |author2=C. Alexander|author3=P. Robinson|author4=Y. Richardson |title=Low-Level Winds in Tornadoes and Potential Catastrophic Tornado Impacts in Urban Areas |journal=[[Bulletin of the American Meteorological Society]] |volume=88 |issue=1 |pages=31–46 |publisher=[[American Meteorological Society]] |date=January 2007 |doi=10.1175/BAMS-88-1-31 |bibcode = 2007BAMS...88...31W |doi-access=free }}</ref> The DOW measured a complex [[Multiple-vortex tornado|multi-vortex]] structure,<ref name="multivortex">{{cite journal |last=Wurman |first=Joshua |author-link= Joshua Wurman |title=The Multiple-Vortex Structure of a Tornado |journal=Weather Forecast. |volume=17 |issue=3 |pages=473–505 |date=June 2002 |doi=10.1175/1520-0434(2002)017<0473:TMVSOA>2.0.CO;2 |issn=1520-0434 |bibcode = 2002WtFor..17..473W|doi-access=free }}</ref> with several vortices containing winds of up to {{convert|abbr=on|257|mph|km/h}} rotating around the tornado. The 3D structure of the tornado has been analyzed in a 2005 article in the ''[[Journal of the Atmospheric Sciences]]'' by Wen-Chau Lee and [[Joshua Wurman]].<ref name="axisymmetric structure">{{cite journal |last=Lee |first=Wen-Chau |author2=J. Wurman |title=Diagnosed Three-Dimensional Axisymmetric Structure of the Mulhall Tornado on 3 May 1999 |journal=J. Atmos. Sci. |volume=62 |issue=7 |pages=2373–93 |date=July 2005 |doi= 10.1175/JAS3489.1 |bibcode = 2005JAtS...62.2373L |url=https://zenodo.org/record/1234581 |doi-access=free }}</ref> The tornado severely damaged or destroyed approximately 60–70% of the 130 homes in Mulhall, destroying the Mulhall/Orlando Elementary School and toppling the city's [[water tower]].

After the tornado dissipated at approximately 10:45&nbsp;p.m. CDT in southeastern [[Noble County, Oklahoma|Noble County]], {{convert|3|mi|km}} northeast of [[Perry, Oklahoma|Perry]], many of the same areas of Logan County struck by the Mulhall tornado were hit again by an F3 tornado. However, this one was produced by a separate supercell that touched down {{convert|2.5|mi|km}} south of [[Crescent, Oklahoma|Crescent]] at 10:56&nbsp;p.m. CDT.<ref name=":0" /> Damage caused by this tornado was indistinguishable from damage caused by the earlier F4 tornado. 25 homes were destroyed and 30 others were damaged near Crescent, with much of the damage believed to have been caused by both tornadoes.
{{clear}}

===Stroud, Oklahoma===
{{Infobox weather event
| name = Stroud, Oklahoma
| image =
| caption              =
| formed               = May 3, 1999, 10:10&nbsp;p.m. [[Central Time Zone|CDT]] ([[UTC−05:00]])
| duration             = 40 minutes
| dissipated           = May 3, 1999, 10:50&nbsp;p.m. CDT (UTC−05:00)}}{{Infobox weather event/Tornado
| basin                = atl
| winds                =
| fujita-scale         = F3
}}{{Infobox weather event/Effects
| year                 = 1999 
| deaths               = 
| injuries             = 7
| damages              =
}}{{Infobox weather event/Footer
| season = 
}}

At 10:10&nbsp;p.m. CDT, this intense and damaging tornado touched down {{convert|3|mi|km}} north-northeast of [[Sparks, Oklahoma|Sparks]] in [[Lincoln County, Oklahoma]], with only sporadic tree damage occurring as it tracked north-northeast toward [[Davenport, Oklahoma|Davenport]]. Scattered damage of high-end F0 to low-end F1 intensity occurred to some homes and businesses on the southeast side of Davenport, though a house located just south of town lost more than half of its roof. As the tornado continued to track northeast, parallel with [[Interstate 44 (Oklahoma)|Interstate&nbsp;44]] and [[Oklahoma State Highway 66|State Highway 66]], [[Stroud, Oklahoma|Stroud]] took a direct hit as the storm intensified to F2 strength; the trucking terminal of the Sygma food distribution warehouse on the west side of town was destroyed with some girders and siding from the warehouse thrown northwest across [[U.S. Route 66 in Oklahoma|State Highway 66]], and the Stroud Municipal Hospital suffered significant roof damage, which resulted in significant water damage within the building. The most severe damage, consistent with an F3 tornado, occurred at the Tanger Outlet Mall at 10:39&nbsp;p.m. CDT with almost all of the stores suffering roof damage at minimum, though sections of seven storefronts were destroyed and the exterior walls of the Levi's store were collapsed inward. The mall was evacuated in advance of the tornado, resulting in no injuries or loss of life in the building. The tornado finally dissipated {{convert|1|mi|km}} south of Stroud Lake at 10:50&nbsp;p.m. CDT.<ref name=":0" />

While there were no fatalities overall in Stroud, the economic impact of the tornado has been compared to the loss of Tinker Air Force Base, [[General Motors]], and a major regional hospital for the Stroud region as compared to Oklahoma City at that time. Approximately 800 jobs were lost in a community of approximately 3,400 people due to the damage of the Sygma distribution warehouse and Tanger Outlet Mall, neither of which were rebuilt.<ref>{{cite web|url=http://www.fundinguniverse.com/company-histories/Tanger-Factory-Outlet-Centers-Inc-Company-History.html|title=History of Tanger Factory Outlet Centers, Inc. – FundingUniverse|website=www.fundinguniverse.com}}</ref> Stroud's recovery was later complicated by the [[September 11, 2001, terrorist attacks]], although the town has since recovered as a result of higher oil and gas prices. Local leading industries include Service King, an oilfield manufacturing facility, and Mint Turbines, a helicopter engine reconditioning facility. Stroud is also now a downloading facility location for oil produced in the northern United States into the [[Cushing, Oklahoma|Cushing]] pipeline network.
{{clear}}

===Other tornadoes===
The May&nbsp;3 tornado event was part of a three-day event that included tornadoes in the [[United States|states]] of [[Kansas]], [[Texas]] and [[Tennessee]]. A deadly F4 tornado that tracked {{convert|24|mi|km}} across south-central Kansas killed six people in [[Haysville, Kansas|Haysville]] and [[Wichita, Kansas|Wichita]] during the late evening of May&nbsp;3. Other fatalities during the event included one person killed in Texas on May&nbsp;4 by an F3 tornado that tracked {{convert|71.5|mi|km}} from near [[Winfield, Texas]], to southwest of [[Mineral Springs, Arkansas]], and three people killed in [[Tennessee]] on May&nbsp;5 and 6 by an F4 tornado that struck the town of [[Linden, Tennessee|Linden]].<ref>{{cite web|url=http://www.srh.noaa.gov/ohx/?n=stormsurvey05051999 |title=Linden F4 Tornado of May 5, 1999 |publisher=Srh.noaa.gov |access-date=2012-08-15}}</ref>
{{clear}}

==Non-tornadic events==
Flash flooding killed one person in [[Camden County, Missouri]], on May 4.<ref>{{cite web|work=National Climatic Data Center|publisher=National Oceanic and Atmospheric Administration|year=2013|access-date=June 9, 2013|title=Missouri Event Report: Flash Flood|url=http://www.ncdc.noaa.gov/stormevents/eventdetails.jsp?id=5697903}}</ref> On May 6, lightning struck and killed a man in [[Cobbtown, Georgia]].<ref>{{cite web|work=National Climatic Data Center|publisher=National Oceanic and Atmospheric Administration|year=2013|access-date=June 9, 2013|title=Georgia Event Report: Lightning|url=http://www.ncdc.noaa.gov/stormevents/eventdetails.jsp?id=5698596}}</ref>

==Aftermath==
===Disaster assistance===
{| class="wikitable" style="margin:0 0 0.5em 1em;float:right;"
|-
! colspan="4" style= background:#DCDCDC; color:#FFFFFF; border: 2px solid #D33A5D | Structural damage in Oklahoma<ref>{{cite web|publisher=Risk Management Solutions|year=2009|access-date=October 2, 2010|title=The 1999 Oklahoma Tornado Outbreak: 10-Year Retrospective|url=http://www.rms.com/Publications/1999_Oklahoma_Tornado_Outbreak.pdf|archive-date=June 1, 2011|archive-url=https://web.archive.org/web/20110601123752/http://www.rms.com/Publications/1999_Oklahoma_Tornado_Outbreak.pdf|url-status=dead}}</ref>
|-
!
! Oklahoma and<br>Cleveland counties
! Other<br>counties
|-
| Homes destroyed
| style="text-align:center;"|1,780
| style="text-align:center;"|534
|-
| Homes damaged
| style="text-align:center;"|6,550
| style="text-align:center;"|878
|-
| Businesses destroyed
| style="text-align:center;"|85
| style="text-align:center;"|79
|-
| Businesses damaged
| style="text-align:center;"|42
| style="text-align:center;"|54
|-
| Public buildings destroyed
| style="text-align:center;"|4
| style="text-align:center;"|7
|-
| Apartments destroyed
| style="text-align:center;"|473
| style="text-align:center;"|568
|-
|}

On May&nbsp;3–4, the day after the initial outbreak event, [[United States President|President]] [[Bill Clinton]] signed a federal disaster declaration for eleven Oklahoma counties. In a press statement by the [[Federal Emergency Management Agency]] (FEMA), then-director [[James Lee Witt]] stated that "The President is deeply concerned about the tragic loss of life and destruction caused by these devastating storms."<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 4, 1999 |access-date=October 2, 2010 |title=President Declares Major Disaster for Oklahoma |url=http://www.fema.gov/news/newsrelease.fema?id=9737 |url-status=dead |archive-url=https://web.archive.org/web/20100607180426/http://www.fema.gov/news/newsrelease.fema?id=9737 |archive-date=June 7, 2010 }}</ref> The [[American Red Cross]] opened ten shelters overnight, housing 1,600 people immediately following the disaster, decreasing to 500 people by May&nbsp;5. On May&nbsp;5, several emergency response and damage assessment teams from FEMA were deployed to the region. The [[United States Department of Defense]] deployed the [[249th Engineer Battalion (United States)|249th Engineering Battalion]] and placed the [[U.S. Army Corps of Engineers]] on standby for assistance. Medical and mortuary teams were also sent by the [[United States Department of Health and Human Services|U.S. Department of Health and Human Services]].<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 5, 1999 |access-date=October 2, 2010 |title=Oklahoma/Kansas Tornado Disaster Update |url=http://www.fema.gov/news/newsrelease.fema?id=9689 |url-status=dead |archive-url=https://web.archive.org/web/20100607180145/http://www.fema.gov/news/newsrelease.fema?id=9689 |archive-date=June 7, 2010 }}</ref> By May 6, donation centers and phone banks were being established to create funds for victims of the tornadoes.<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 6, 1999 |access-date=October 2, 2010 |title=Plains States Tornado Update |url=http://www.fema.gov/news/newsrelease.fema?id=9688 |url-status=dead |archive-url=https://web.archive.org/web/20100607181739/http://www.fema.gov/news/newsrelease.fema?id=9688 |archive-date=June 7, 2010 }}</ref> Within the first few days of the disaster declaration, relief funds were sent to families requesting aid. Roughly $180,000 had been approved by FEMA for disaster housing assistance by May&nbsp;9.<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 9, 1999 |access-date=October 2, 2010 |title=First Checks Approved for Oklahoma Storm Victims |url=http://www.fema.gov/news/newsrelease.fema?id=9726 |url-status=dead |archive-url=https://web.archive.org/web/20100607181042/http://www.fema.gov/news/newsrelease.fema?id=9726 |archive-date=June 7, 2010 }}</ref>

Debris removal began on May&nbsp;12 as seven cleanup teams were sent to the region with more teams expected to join over the following days.<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 12, 1999 |access-date=October 2, 2010 |title=Debris Removal Underway in Oklahoma City, Mulhall, and Choctaw; Stroud Set for Thursday |url=http://www.fema.gov/news/newsrelease.fema?id=9731 |url-status=dead |archive-url=https://web.archive.org/web/20100607181800/http://www.fema.gov/news/newsrelease.fema?id=9731 |archive-date=June 7, 2010 }}</ref> That day, FEMA also granted seven Oklahoma counties ([[Canadian County, Oklahoma|Canadian]], [[Craig County, Oklahoma|Craig]], Grady, Lincoln, Logan, Noble and Oklahoma) eligibility for federal financial assistance.<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 12, 1999 |access-date=October 2, 2010 |title=Seven Oklahoma Counties Get Expanded Disaster Assistance |url=http://www.fema.gov/news/newsrelease.fema?id=9730 |url-status=dead |archive-url=https://web.archive.org/web/20100607180302/http://www.fema.gov/news/newsrelease.fema?id=9730 |archive-date=June 7, 2010 }}</ref> Roughly $1.6 million in disaster funds had been approved for housing and business loans by May&nbsp;13,<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 13, 1999 |access-date=October 2, 2010 |title=Oklahoma Tornado Disaster Update |url=http://www.fema.gov/news/newsrelease.fema?id=9732 |url-status=dead |archive-url=https://web.archive.org/web/20100607180114/http://www.fema.gov/news/newsrelease.fema?id=9732 |archive-date=June 7, 2010 }}</ref> increasing to more than $5.9 million over the following five days.<ref>{{cite web|publisher=Federal Emergency Management Agency |date=May 18, 1999 |access-date=October 2, 2010 |title=Oklahoma Disaster Recovery News Summary |url=http://www.fema.gov/news/newsrelease.fema?id=9717 |url-status=dead |archive-url=https://web.archive.org/web/20100607181810/http://www.fema.gov/news/newsrelease.fema?id=9717 |archive-date=June 7, 2010 }}</ref> Applications for federal aid continued through June, with state aid approvals reaching $54 million on June&nbsp;3. According to FEMA, more than 9,500 Oklahoma residents applied for federal aid during the allocated period in the wake of the tornadoes, including 3,800 in Oklahoma County and 3,757 in Cleveland County. Disaster recovery aid for the tornadoes totaled to roughly $67.8 million by July&nbsp;2.<ref>{{cite web|publisher=Federal Emergency Management Agency |date=July 7, 1999 |access-date=October 3, 2010 |title=Almost 9,500 Oklahomans Register For Disaster Recovery Aid More Than $67.8 Million In Grants And Loans Approved |url=http://www.fema.gov/news/newsrelease.fema?id=9694 |url-status=dead |archive-url=https://web.archive.org/web/20100608004335/http://www.fema.gov/news/newsrelease.fema?id=9694 |archive-date=June 8, 2010 }}</ref>

===Concerns with using overpasses as storm shelters===
{| class="wikitable" style="margin:0 0 0.5em 1em;float:right;"
|-
! colspan="4" style= background:#DCDCDC; color:#FFFFFF; border: 2px solid #D33A5D | Outbreak death toll
|- 
! State
! Fatalities
! County
! County total 
|-
| [[Kansas]]
| '''6'''
|[[Sedgwick County, Kansas|Sedgwick]]
|6
|-
| rowspan="8" |[[Oklahoma]]
| rowspan="8" |'''40'''
|[[Cleveland County, Oklahoma|Cleveland]]
|11
|-
|[[Grady County, Oklahoma|Grady]]
|12
|-
|[[Kingfisher County, Oklahoma|Kingfisher]]
|1
|-
|[[Logan County, Oklahoma|Logan]]
|1
|-
|[[McClain County, Oklahoma|McClain]]
|1
|-
|[[Payne County, Oklahoma|Payne]]
|1
|-
|[[Pottawatomie County, Oklahoma|Pottawatomie]]
|1
|-
|[[Oklahoma County, Oklahoma|Oklahoma]]
|12
|-
| [[Tennessee]]
| '''3'''
|[[Perry County, Tennessee|Perry]]
|3
|-
| [[Texas]]
| '''1'''
|[[Titus County, Texas|Titus]]
|1
|-
| Total
| '''50'''
|colspan=2|
|-
| colspan="4" style="text-align:center;"| <small>All deaths were tornado-related</small>
|}
From a meteorological and safety standpoint, the tornado called into question the use of highway overpasses as shelters from tornadoes. Prior to the events on May&nbsp;3, 1999, videos of people taking shelter in overpasses during tornadoes in the past (such as an infamous video from the [[April 26, 1991 tornado outbreak]] taken by a news crew from Wichita NBC affiliate [[KSNW]]) created public misunderstanding and complacency that overpasses provided adequate shelter from tornadoes. Although meteorologists had questioned the safety of these structures for nearly 20 years, there had been no evidence supporting incidents involving loss of life.<ref>{{cite web|author1=Daniel J. Miller |author2=Charles A. Doswell III |author3=Harold E. Brooks |author4=Gregory J. Stumpf |author5=Erik Rasmussen |publisher=National Weather Service in Norman, Oklahoma|year=1999|access-date=October 3, 2010|title=Highway Overpasses as Tornado Shelters|page=1|url=http://www.weather.gov/oun/safety-overpass-slide01| archive-url= https://web.archive.org/web/20101113220800/http://www.weather.gov/oun/safety-overpass-slide01| archive-date= 13 November 2010 | url-status= live}}</ref> Three overpasses were directly struck by tornadoes during the May&nbsp;3 outbreak, resulting in fatalities at each location. Two occurred as a result of the Bridge Creek–Moore F5, while the third occurred in rural [[Payne County, Oklahoma|Payne County]], which was struck by an F2 tornado.<ref>{{cite web|author1=Daniel J. Miller|author2=Charles A. Doswell III|author3=Harold E. Brooks|author4=Gregory J. Stumpf|author5=Erik Rasmussen|publisher=National Weather Service in Norman, Oklahoma|year=1999|access-date=October 3, 2010|title=Highway Overpasses as Tornado Shelters: Events on May 3, 1999|page=5|url=http://www.weather.gov/oun/safety-overpass-slide05|archive-date=February 11, 2017|archive-url=https://web.archive.org/web/20170211081117/http://www.weather.gov/oun/safety-overpass-slide05|url-status=dead}}</ref> According to a study by the National Oceanic and Atmospheric Administration, seeking shelter in an overpass "is to become a stationary target for flying debris"; the wind channeling effect that occurs within these structures along with an increase in wind speeds above ground level, changing of wind direction when the tornado vortex passes, and the fact most overpasses do not have girders for people to take shelter between also provide little to no protection.<ref>{{cite web|author1=Daniel J. Miller |author2=Charles A. Doswell III |author3=Harold E. Brooks |author4=Gregory J. Stumpf |author5=Erik Rasmussen |publisher=National Weather Service in Norman, Oklahoma|year=1999|access-date=October 3, 2010|title=Highway Overpasses as Tornado Shelters: Highway Overpasses Are Inadequate Tornado Sheltering Areas|page=6|url=http://www.weather.gov/oun/safety-overpass-slide06}}</ref>
{{clear}}

==See also==
{{Commons category}}
*[[Climate of Oklahoma City]]
*[[List of North American tornadoes and tornado outbreaks]]
*[[Tornado outbreak of April 28–30, 1960]]
*''[[Ultimate Tornado]]'' (documentary)
*[[2013 Moore tornado]] – Crossed some of the same areas as the 1999 F5

==References==
{{Reflist}}

==External links==
*[http://newsok.com/may3 May 3, 1999 Oklahoma Tornado Special Report - The Oklahoman]
*{{usurped|1=[https://web.archive.org/web/20110128201408/http://www.tornadohistoryproject.com/outbreaks/the-great-plains-tornado-outbreak-1999 Great Plains Outbreak of 1999]}} Tornado History Project
*[http://www.weather.gov/oun/events-19990503 The Great Plains Tornado Outbreak of May 3-4, 1999] (National Weather Service, Norman, Oklahoma)
*[http://www.cimms.ou.edu/~schultz/F5/ The 3 May 1999 Oklahoma Tornadoes] (David Schultz, [[CIMMS]])
*[https://maps.google.com/maps?f=q&hl=en&geocode=&q=stroud,+Oklahoma&ie=UTF8&ll=35.754314,-96.655312&spn=0.01912,0.039911&t=k&z=15&om=1 Google Maps' location of Stroud, Oklahoma, with the bulldozed lot of the former Tanger Outlet Mall in the upper left of the screen, just north of Interstate 44]
*[https://web.archive.org/web/20070927185037/http://www.koco.com/may3/index.html May 3 Oklahoma Tornado] Special video section from [[KOCO-TV]]
*[http://xpda.com/mooretornado/ Moore, Oklahoma Tornado Photos, May 1999] Aerial Photos of Moore Oklahoma taken three days after the May 3, 1999, tornado
*{{Cite journal|last1 = Anastassia M. |first1 = Makarieva |last2 = Gorshkov |first2 = Victor G. |last3 = Nefiodov |first3 = Andrei V. |title =  Condensational theory of stationary tornadoes |journal = Physics Letters A |volume = 375 |issue = 24 |pages = 2259–2261 |date = 2012 |arxiv=1208.2580 |doi = 10.1016/j.physleta.2011.04.023 |bibcode = 2011PhLA..375.2259M |s2cid = 100544331 }}

{{1999 tornado outbreaks}}
{{Wisconsin tornado events}}

{{DEFAULTSORT:1999-05-02 Tornado, Oklahoma}}
[[Category:F5, EF5 and IF5 tornadoes]]
[[Category:Tornadoes of 1999|05-02 Oklahoma]]
[[Category:Tornadoes in Kansas]]
[[Category:Tornadoes in Oklahoma]]
[[Category:Tornadoes in Texas]]
[[Category:Tornadoes in Tennessee]]
[[Category:Tornado outbreaks in the United States]]
[[Category:1999 in Tennessee|05-02 Tornado]]
[[Category:1999 in Texas|05-02 Tornado]]
[[Category:1999 natural disasters in the United States|Tornado, 05-02]]
[[Category:May 1999 in the United States|Tornado, Oklahoma, 03]]