On May 24–25, 1957, a tornado outbreak primarily affected the Western High Plains, Central Great Plains, and Central Oklahoma/Texas Plains of the United States.[nb 2] 45 tornadoes touched down over the area, most of which took place across northern and western Texas, in addition to southern Oklahoma. Overall activity initiated over eastern New Mexico and spread northeastward as far as southwestern Wisconsin. The strongest tornado, which occurred in southern Oklahoma on May 24, was assigned a rating of F4 near Lawton.[nb 3] Anomalously, some tornadoes touched down during the early morning hours, rather than late afternoon or early evening, when daytime heating typically peaks.[15]
Background
| State | Total | County | County total |
|---|---|---|---|
| Oklahoma | 4 | Cotton | 4 |
| Totals | 4 | ||
| All deaths were tornado-related | |||
The week of May 20–26, 1957, was the most prolific in terms of tornado activity recorded to date.[18] On May 20–21, an upper-level trough traversed the Central United States. As it did so, a significant tornado outbreak took place over portions of Kansas, Nebraska, Missouri, and Oklahoma. Cold upper air temperatures and marginal surface dew points produced severe weather across the southern and central Great Plains. On May 21, the vigorous shortwave trough, co-located with a deep surface low, produced a violent tornado in Minnesota, while additional tornadoes killed fifteen people in Missouri. At the time, a potent mid-level jet stream produced winds of 70 to 80 kn (81 to 92 mph; 130 to 150 km/h), providing ample wind shear for tornado-producing supercells.[15]
On May 22, surface weather analysis indicated another low-pressure area over southwestern Oklahoma. In attendance, a series of cold fronts affected western Texas and eastern New Mexico. During their passage, outflow from thunderstorms affected the warm sector, farther to the southeast. On May 23, dew points rose across western Texas, and temperatures reached 77 °F (25 °C) in the warm sector. By 06:00 UTC (1:00 a.m. CDT/midnight MDT) on May 24, dew points of 60 to 65 °F (16 to 18 °C) surged into southeastern New Mexico on both sides of a warm front. A new surface low-pressure area also developed over New Mexico. Nine hours later, lifted index values increased to -11, coincident with surface-based convective available potential energy (CAPE) values near 3,500 J/kg. Based on observations from weather stations, the first thunderstorms developed by 16:30 UTC (11:30 a.m. CDT/10:30 a.m. MDT).[15][19]
Confirmed tornadoes
| FU | F0 | F1 | F2 | F3 | F4 | F5 | Total |
|---|---|---|---|---|---|---|---|
| 0 | 15 | 18 | 8 | 3 | 1 | 0 | 45 |
| "FU" denotes unclassified but confirmed tornadoes. | |||||||
- In addition to these tornadoes, there were at least three unconfirmed events. One tornado, sighted around 11:17 a.m. CST (17:17 UTC), occurred 20 mi (32 km) northwest of Wildorado, Texas, and may have developed in Deaf Smith County. It remained over rural areas and inflicted no damage. Additionally, at least one undocumented tornado was reported southeast and east of Midland around 6:30–7:15 p.m. (00:30–01:15 UTC).[15] A brief tornado also may have touched down near Moore in the Oklahoma City metropolitan area, breaking tree branches and windows.[17] None of these tornadoes was officially recorded in the National Weather Service database.[4]
May 24 event
| F# | Location | County / Parish | State | Start coord. |
Time (UTC) | Path length | Max. width | Summary |
|---|---|---|---|---|---|---|---|---|
| F2 | WNW of St. Vrain to E of Hollene | Curry | NM | 34°26′N 103°33′W / 34.43°N 103.55°W | 11:00–? | 36.5 miles (58.7 km) | 37 yards (34 m) | This long-tracked tornado family likely consisted of as many as six tornadoes, each of which generated narrow swaths of damage. It began west of Clovis and ended southeast of Bellview. Intermittent damage to farms occurred between Grier and Hollene, including the destruction of two barns.[16][21][22] |
| F1 | SW of Brown | Bryan | OK | 34°04′N 96°30′W / 34.07°N 96.50°W | 16:40–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A brief tornado struck twenty stanchions and mangled several boats.[22] |
| F2 | S of Bovina to SE of Bushland | Parmer, Deaf Smith, Potter | TX | 34°26′N 102°53′W / 34.43°N 102.88°W | 16:45–? | 70.1 miles (112.8 km) | 33 yards (30 m) | This long-lived tornado family traveled northeastward to a point near Bushland, west of Amarillo. After damaging an orchard and farmland near Bovina, the tornado lifted near Hub before reforming near Friona. Near Friona and Black, the tornado damaged several homes, and destroyed structures on eight different farms. Funnel clouds in the parent storm instigated traffic accidents in Hereford that injured some people.[23][22][16] |
| F0 | N of Enochs | Bailey | TX | 33°57′N 102°46′W / 33.95°N 102.77°W | 17:20–? | 0.5 miles (0.80 km) | 50 yards (46 m) | Rural power poles and electrical wires sustained damage.[22] |
| F0 | Hereford area | Deaf Smith | TX | 34°49′N 102°24′W / 34.82°N 102.40°W | 17:30–? | 1 mile (1.6 km) | 10 yards (9.1 m) | This brief tornado formed over open land near Hereford and produced no damage.[22] |
| F3 | Sudan to Olton | Lamb | TX | 34°11′N 102°51′W / 34.18°N 102.85°W | 18:38–18:45 | 1.9 miles (3.1 km) | 200 yards (180 m) | This strong tornado first struck Sudan, then lifted and touched down in Olton. The tornado destroyed a total of 77 homes in and near Olton, a number of which were sited on farms outside town. The southern section of Olton received the most severe damage. The tornado lofted a vehicle 1⁄2 mi (0.80 km) as well. Three injuries were attributed to the tornado.[24][16][15][25] |
| F3 | ENE of Tahoka to NE of Ralls | Lynn, Lubbock, Crosby | TX | 33°10′N 101°47′W / 33.17°N 101.78°W | 19:00–20:00 | 37.3 miles (60.0 km) | 200 yards (180 m) | This strong, long-tracked tornado family impacted Tahoka, Wilson, Slaton, and Savage, damaging, destroying, or unroofing more than 120 structures. Two homes and two barns were also destroyed west and north of Ralls. The tornado eventually dissipated east of Cone. Tornado researcher Thomas P. Grazulis listed the total path length as being 50 mi (80 km) and classified the tornado as an F2. One injury occurred along the path.[16][15][26] |
| F1 | NW of Cotton Center to ENE of Hale Center | Hale | TX | 34°00′N 102°00′W / 34.00°N 102.00°W | 19:30–? | 10.5 miles (16.9 km) | 10 yards (9.1 m) | One home, located north of Cotton Center, was moved 100 ft (30 m) off its foundation and torn apart. Three homes were unroofed or destroyed near the end of the path, southwest of Plainview. Nine homes also sustained minor damage. Four funnel clouds were reported nearby. Grazulis listed this tornado as an F2.[16][15] |
| F0 | N of Amarillo | Potter | TX | 35°19′N 101°50′W / 35.32°N 101.83°W | 19:50–? | 0.3 miles (0.48 km) | 50 yards (46 m) | Unknown[4] |
| F0 | E of Edmonson | Hale | TX | 34°17′N 101°53′W / 34.28°N 101.88°W | 20:00–? | 0.5 miles (0.80 km) | 10 yards (9.1 m) | Houses, barns, and trailers were destroyed near Halfway. Several livestock died as well. The tornado formed from the same storm as the Olton tornado.[16][24] |
| F3 | NNE of Lenorah | Martin | TX | 32°19′N 101°52′W / 32.32°N 101.87°W | 20:45–? | 1.5 miles (2.4 km) | 83 yards (76 m) | In Lenorah, this tornado impacted five homes, one of which was destroyed. This was one of two or three tornadoes in a 30-mile-long (48 km) family. Grazulis listed this tornado as an F2. One injury occurred.[27][16] |
| F1 | NNW of Yoder | Goshen | WY | 41°56′N 104°18′W / 41.93°N 104.30°W | 21:00–? | 2.5 miles (4.0 km) | 13 yards (12 m) | Numerous funnel clouds and/or tornadoes were reported, but only one touchdown was confirmed. A tornado damaged or destroyed a mobile home and outbuildings near Yoder and south of Torrington.[24] |
| F1 | NE of Swink | Otero | CO | 38°03′N 103°35′W / 38.05°N 103.58°W | 21:30–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A brief tornado uplifted a rural outbuilding.[28] |
| F1 | E of Pierce | Weld | CO | 40°38′N 104°40′W / 40.63°N 104.67°W | 22:00–? | 4 miles (6.4 km) | 10 yards (9.1 m) | An empty farmhouse was destroyed, along with haystacks and machinery.[24] |
| F1 | N of Burlington | Kit Carson | CO | 39°26′N 102°16′W / 39.43°N 102.27°W | 22:00–? | 0.4 miles (0.64 km) | 10 yards (9.1 m) | Related to the Swink event, this small tornado destroyed a chicken coop.[28] |
| F1 | WSW of Pierce | Weld | CO | 40°38′N 104°46′W / 40.63°N 104.77°W | 22:00–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A brief tornado destroyed a deserted farmhouse.[24] |
| F1 | S of Davidson to S of Frederick | Tillman | OK | 34°12′N 99°04′W / 34.20°N 99.07°W | 22:30–? | 9.7 miles (15.6 km) | 10 yards (9.1 m) | Farms were extensively damaged. Utility lines and power poles were downed.[24] |
| F1 | WNW of Belle Plaine | Sumner | KS | 37°24′N 97°18′W / 37.40°N 97.30°W | 23:05–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A brief tornado touched down and then lifted.[29] |
| F4 | W of Cookietown to S of Lawton | Cotton, Comanche | OK | 34°16′N 98°30′W / 34.27°N 98.50°W | 23:30–? | 21.6 miles (34.8 km) | 880 yards (800 m) | 4 deaths – This large, violent tornado destroyed 12 homes, some of which were levelled. The swath of F4 damage occurred south of Lawton. One car was transported 100 yd (91 m); although the vehicle crashed in a pond, the driver was not injured. The tornado damaged or destroyed several farms as well, and numerous farm animals died in its path. Two couples died and five people sustained injuries.[29][16][30] |
| F2 | SSW of Wynnewood to SE of Pink | Garvin, Pottawatomie | OK | 34°37′N 97°11′W / 34.62°N 97.18°W | 00:00–01:45 | 30.8 miles (49.6 km) | 440 yards (400 m) | This damaging tornado family first destroyed a barn, then impacted an oil refinery in Wynnewood. Subsequently, the tornado wrecked four homes, a school, and many barns southeast of Pauls Valley. The tornado may have lifted until it encountered and destroyed frame buildings in Wanette. The tornado finally destroyed a barn northwest of Macomb before dissipating. Grazulis listed the tornado as an F3.[16][31] |
| F2 | NNW of Midland | Martin | TX | 32°09′N 102°08′W / 32.15°N 102.13°W | 00:28–? | 2 miles (3.2 km) | 10 yards (9.1 m) | This brief tornado downed utility poles near State Highway 158 and reportedly destroyed farmhouses northwest of Stanton.[16] |
| F1 | N of Brandon | Perkins | NE | 40°53′N 101°56′W / 40.88°N 101.93°W | 01:30–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | Tornado reported.[29] |
| F0 | NW of Cache | Comanche | OK | 34°42′N 98°42′W / 34.70°N 98.70°W | 02:00–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A tornado formed over remote, hilly country in the Wichita Mountains Wildlife Refuge.[29] |
| F1 | E of Goree | Baylor | TX | 33°29′N 99°24′W / 33.48°N 99.40°W | 02:30–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A tornado was witnessed southwest of Seymour.[32] |
| F1 | WSW of Purcell | McClain | OK | 35°00′N 97°24′W / 35.00°N 97.40°W | 03:00–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A tornado unroofed a barn, blew down trees, and damaged outbuildings on a farm.[32] |
| F2 | W of Marlow | Stephens | OK | 34°39′N 98°00′W / 34.65°N 98.00°W | 03:00–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A strong tornado struck the community of Denton, killed 100 turkeys, and destroyed a chicken coop, a barn, and a home. Several farms reported extensive damage, and 2-by-4-inch (51 by 102 mm) boards pierced a house as well. Additionally, a bus transporting 20 passengers was cast into a ditch, but none of the passengers was injured.[16][32] |
| F0 | Baxter Springs area | Cherokee | KS | 37°01′N 94°44′W / 37.02°N 94.73°W | 04:00–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | Unknown[4] |
| F1 | WSW of Quapaw | Ottawa | OK | 36°57′N 94°48′W / 36.95°N 94.80°W | 04:00–? | 1 mile (1.6 km) | 10 yards (9.1 m) | A tornado caused minor damage in Quapaw and destroyed a derrick at a mine east of Picher. An EF4 tornado later hit the Picher area on May 10, 2008.[32] |
| F0 | SE of Mulvane | Sumner | KS | 37°27′N 97°13′W / 37.45°N 97.22°W | 04:00–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | Unknown[4] |
| F2 | SSW of Duncan | Stephens | OK | 34°28′N 97°58′W / 34.47°N 97.97°W | 04:25–? | 2.5 miles (4.0 km) | 10 yards (9.1 m) | This tornado splintered trees, destroyed television antennas, and badly damaged a mobile home in Duncan. Grazulis did not list this tornado as an F2 or stronger.[32][16] |
| F0 | NE of Morris to N of Boynton | Okmulgee, Muskogee | OK | 35°38′N 95°50′W / 35.63°N 95.83°W | 04:25–05:10 | 10.8 miles (17.4 km) | 10 yards (9.1 m) | A tornado affected unpopulated areas near Morris and Boynton.[32] |
May 25 event
| F# | Location | County / Parish | State | Start coord. |
Time (UTC) | Path length | Max. width | Summary |
|---|---|---|---|---|---|---|---|---|
| F0 | NNE of Hanna | McIntosh | OK | 35°18′N 95°50′W / 35.30°N 95.83°W | 05:43–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | Highway patrol sighted a tornado southeast of Henryetta.[32] |
| F0 | WSW of Checotah | McIntosh | OK | 35°26′N 95°36′W / 35.43°N 95.60°W | 05:45–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A tornado was sighted, but no damage was reported.[32] |
| F2 | Coleman area | Johnston | OK | 34°16′N 96°25′W / 34.27°N 96.42°W | 06:05–? | 1 mile (1.6 km) | 200 yards (180 m) | A new school was partly unroofed and damage was extensive to buildings and trees. Two funnel clouds were seen. Grazulis did not list this tornado as an F2 or stronger.[28][16] |
| F1 | W of Lehigh | Coal | OK | 34°16′N 96°25′W / 34.27°N 96.42°W | 06:10–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A tornado destroyed sheds and damaged a house and a barn.[28] |
| F1 | ESE of Steedman to SE of Atwood | Pontotoc, Hughes | OK | 34°48′N 96°25′W / 34.80°N 96.42°W | 06:15–? | 11.5 miles (18.5 km) | 150 yards (140 m) | Near Allen, the tornado unroofed a home and destroyed a barn. Trees and outbuildings were prostrated near Atwood, and a number of farmsteads were damaged along the path. Grazulis listed this tornado as an F2.[16][28] |
| F0 | SW of Mountain Valley (1st tornado) | Garland | AR | 34°36′N 93°06′W / 34.60°N 93.10°W | 12:00–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | Intermittent, slight damage occurred.[28] |
| F0 | SW of Mountain Valley (2nd tornado) | Garland | AR | 34°36′N 93°06′W / 34.60°N 93.10°W | 12:06–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | See previous event.[28] |
| F0 | NW of Oak Trail Shores | Hood | TX | 32°32′N 97°54′W / 32.53°N 97.90°W | 20:00–? | 0.5 miles (0.80 km) | 10 yards (9.1 m) | A tornado briefly struck a ranch east of Lipan.[28] |
| F1 | E of Maple Lake | Wright | MN | 45°14′N 93°59′W / 45.23°N 93.98°W | 20:38–? | 0.7 miles (1.1 km) | 20 yards (18 m) | A short-lived tornado levelled a barn and felled a number of trees.[28] |
| F1 | NW of Grover | Codington | SD | 44°49′N 97°17′W / 44.82°N 97.28°W | 20:45–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | Unknown[4] |
| F0 | S of Fredericksburg | Chickasaw | IA | 42°57′N 92°12′W / 42.95°N 92.20°W | 21:30–? | 0.1 miles (0.16 km) | 10 yards (9.1 m) | A brief tornado damaged farmsteads and cropland.[28] |
| F2 | N of Bloomington to NE of Fennimore | Grant | WI | 42°54′N 90°55′W / 42.90°N 90.92°W | 22:30–? | 15.6 miles (25.1 km) | 400 yards (370 m) | Grazulis did not list this tornado as an F2 or stronger.[16] |
| F1 | ENE of Lometa | Lampasas | TX | 31°13′N 98°23′W / 31.22°N 98.38°W | 00:15–? | 0.5 miles (0.80 km) | 50 yards (46 m) | A carport was unroofed.[33] |
| F0 | SE of Stanton | Montgomery | IA | 40°55′N 95°07′W / 40.92°N 95.12°W | 05:15–? | 4.1 miles (6.6 km) | 1,000 yards (910 m) | A tornado, large but weak, damaged a grandstand and farm buildings.[33][34] |
See also
Notes
- ^ All losses are in 1957 USD unless otherwise noted.
- ^ An outbreak is generally defined as a group of at least six tornadoes (the number sometimes varies slightly according to local climatology) with no more than a six-hour gap between individual tornadoes. An outbreak sequence, prior to (after) the start of modern records in 1950, is defined as a period of no more than two (one) consecutive days without at least one significant (F2 or stronger) tornado.[5][6][7][8][9]
- ^ The Fujita scale was devised under the aegis of scientist T. Theodore Fujita in the early 1970s. Prior to the advent of the scale in 1971, tornadoes in the United States were officially unrated.[10][11] While the Fujita scale has been superseded by the Enhanced Fujita scale in the U.S. since February 1, 2007,[12] Canada utilized the old scale until April 1, 2013;[13] nations elsewhere, like the United Kingdom, apply other classifications such as the TORRO scale.[14]
- ^ a b All dates are based on the local time zone where the tornado touched down; however, all times are in Coordinated Universal Time and dates are split at midnight CST/CDT for consistency.
- ^ a b Prior to 1994, only the average widths of tornado paths were officially listed.[20]
References
- ^ National Weather Service (30 September 2019). Grazulis, Thomas P.; Grazulis, Doris (eds.). Tornado History Project: Maps and Statistics. Tornado History Project (Report). The Tornado Project of Environmental Films. Retrieved 14 January 2021.
- ^ National Weather Service (September 2020). Events reported between 05/24/1957 and 05/25/1957 (2 days). Storm Events Database (Report). National Centers for Environmental Information. Retrieved 14 January 2021.
- ^ National Weather Service (September 2020). Events reported between 05/24/1957 and 05/25/1957 (2 days). Storm Events Database (Report). National Centers for Environmental Information. Retrieved 14 January 2021.
- ^ a b c d e f g h National Weather Service (September 2020). Events reported between 05/24/1957 and 05/25/1957 (2 days). Storm Events Database (Report). National Centers for Environmental Information. Retrieved 14 January 2021.
- ^ Schneider, Russell S.; Brooks, Harold E.; Schaefer, Joseph T. (2004). Tornado Outbreak Day Sequences: Historic Events and Climatology (1875-2003) (PDF). 22nd Conference on Severe Local Storms. Hyannis, Massachusetts: American Meteorological Society. Retrieved 17 September 2019.
- ^ Hagemeyer, Bartlett C. (September 1997). "Peninsular Florida Tornado Outbreaks". Weather and Forecasting. 12 (3). Boston: American Meteorological Society: 400. Bibcode:1997WtFor..12..399H. doi:10.1175/1520-0434(1997)012<0399:PFTO>2.0.CO;2. S2CID 120588681.
- ^ Hagemeyer 1997, p. 401
- ^ Hagemeyer, Bartlett C.; Spratt, Scott M. (2002). Written at Melbourne, Florida. Thirty Years After Hurricane Agnes: the Forgotten Florida Tornado Disaster (PDF). 25th Conference on Hurricanes and Tropical Meteorology. San Diego, California: American Meteorological Society. Archived from the original (PDF) on 16 October 2008. Retrieved 24 November 2019.
- ^ Grazulis, Thomas P. (2001). The Tornado: Nature's Ultimate Windstorm. Norman: University of Oklahoma Press. p. 206. ISBN 978-0-8061-3538-0.
- ^ Grazulis, Thomas P. (July 1993). Significant Tornadoes 1680–1991: A Chronology and Analysis of Events. St. Johnsbury, Vermont: The Tornado Project of Environmental Films. p. 141. ISBN 1-879362-03-1.
- ^ Grazulis, Thomas P. (2001). The Tornado: Nature's Ultimate Windstorm. Norman: University of Oklahoma Press. p. 131. ISBN 978-0-8061-3538-0.
- ^ Edwards, Roger (5 March 2015). "Enhanced F Scale for Tornado Damage". The Online Tornado FAQ (by Roger Edwards, SPC). Storm Prediction Center. Retrieved 25 February 2016.
- ^ "Enhanced Fujita Scale (EF-Scale)". Environment and Climate Change Canada. 6 June 2013. Archived from the original on 3 March 2016. Retrieved 25 February 2016.
- ^ "The International Tornado Intensity Scale". Tornado and Storm Research Organisation. 2016. Archived from the original on 5 March 2016. Retrieved 25 February 2016.
- ^ a b c d e f g Finch, Jonathan D. (9 April 2018). "The May 24, 1957 Tornado Outbreak". Bangladesh Tornadoes. Archived from the original on 23 March 2019. Retrieved 19 November 2019.
- ^ a b c d e f g h i j k l m n o p Grazulis, Thomas P. (July 1993). Significant Tornadoes 1680–1991: A Chronology and Analysis of Events. St. Johnsbury, Vermont: The Tornado Project of Environmental Films. p. 1008. ISBN 1-879362-03-1.
- ^ a b U.S. Weather Bureau (May 1957). "Storm Data and Unusual Weather Phenomena". Climatological Data National Summary. 8 (5). Asheville, North Carolina: National Climatic Data Center: 195–200.
- ^ Dunn, Carlos R. (May 1957). "THE WEATHER AND CIRCULATION OF MAY 1957: A Month with Severe Floods and Devastating Tornadoes in the Southern Plains of the United States" (PDF). Monthly Weather Review. 85 (5). Washington, D.C.: American Meteorological Society: 180. doi:10.1175/1520-0493-85.5.175. Retrieved 20 November 2019.
- ^ "North America Tornado Cases 1950 to 1959". bangladeshtornadoes.org. Retrieved 21 April 2022.
- ^ Brooks, Harold E. (April 2004). "On the Relationship of Tornado Path Length and Width to Intensity". Weather and Forecasting. 19 (2). Boston: American Meteorological Society: 310. Bibcode:2004WtFor..19..310B. doi:10.1175/1520-0434(2004)019<0310:OTROTP>2.0.CO;2. Retrieved 11 September 2019.
- ^ National Weather Service (May 2019). New Mexico Event Report: F2 Tornado. Storm Events Database (Report). National Centers for Environmental Information. Retrieved 20 November 2019.
- ^ a b c d e USWB 1957, p. 195
- ^ National Weather Service (May 2019). Texas Event Report: F2 Tornado. Storm Events Database (Report). National Centers for Environmental Information. Retrieved 20 November 2019.
- ^ a b c d e f USWB 1957, p. 196
- ^ National Weather Service (May 2019). Texas Event Report: F3 Tornado. Storm Events Database (Report). National Centers for Environmental Information. Retrieved 20 November 2019.
- ^ National Weather Service (May 2019). Texas Event Report: F3 Tornado. Storm Events Database (Report). National Centers for Environmental Information. Retrieved 20 November 2019.
- ^ National Weather Service (May 2019). Texas Event Report: F3 Tornado. Storm Events Database (Report). National Centers for Environmental Information. Retrieved 21 November 2019.
- ^ a b c d e f g h i j USWB 1957, p. 199
- ^ a b c d USWB 1957, p. 197
- ^ National Weather Service (May 2019). Texas Event Report: F4 Tornado. Storm Events Database (Report). National Centers for Environmental Information. Retrieved 21 November 2019.
- ^ Dye, Lucius W. (May 1957). Written at Kansas City, Missouri. "Oklahoma – May 1957". Weather Summary. Climatological Data. Oklahoma. 66 (5). Asheville, North Carolina: National Climatic Data Center: 66.
- ^ a b c d e f g h USWB 1957, p. 198
- ^ a b USWB 1957, p. 200
- ^ National Weather Service (September 2020). Iowa Event Report: F0 Tornado. Storm Events Database (Report). National Centers for Environmental Information. Retrieved 14 January 2021.