Early-May 1965 tornado outbreak sequence

Early-May 1965 tornado outbreak sequence

Tornado tracks through Minneapolis–Saint Paul on May 6
Type Tornado outbreak
Duration May 5–8, 1965
Tornadoes confirmed 72
Max rating1 F5 tornado
Duration of tornado outbreak2 3 days, 7 hours, 2 minutes
Damage Estimated $51 Million[1][2]
Areas affected Great Plains and Midwestern United States

1Most severe tornado damage; see Fujita scale

2Time from first tornado to last tornado

The early-May 1965 tornado outbreak sequence[nb 1][nb 2] was a major severe weather event that affected much of the Central United States on May 5–8, 1965. For four consecutive days, tornado outbreaks produced at least three significant (F2+) tornadoes each day, and at least two violent (F4–F5) tornadoes on three of the four days. The entire sequence generated 37 significant tornadoes, including at least nine violent tornadoes, one of which was rated F5. On May 5, two F4s struck Iowa, including a long-tracked tornado family that injured 11 people. On May 6, an outbreak of six strong tornadoes, four of them violent F4s, affected Minneapolis and St. Paul, Minnesota, and has been nicknamed "The Longest Night", killing 13 people and causing major damages—at the time the most damaging single weather event in Minnesota history.[1] Three of the six tornadoes occurred on the ground simultaneously, and two of them hit the section of Minnesota State Highway 100 (now Interstate 694) and University Avenue in the city of Fridley.[4] Both Fridley tornadoes damaged 1,100 homes and destroyed about 425; total losses reached $14.5 million, $5 million of which was to the Fridley school system.

On May 7, three significant tornadoes hit portions of the Upper Midwest, and beginning early on May 8, a major tornado outbreak affected the Great Plains states, particularly in Nebraska and South Dakota. The outbreak on May 8 produced numerous significant, long-lived tornadoes, including at least three violent tornadoes, two of which were actually long-tracked tornado families. A very large F5 tornado struck Tripp County in South Dakota, and two major F4s tracked across parts of Greeley and Antelope Counties in Nebraska. One of the F4s struck the small village of Primrose, almost totally destroying the settlement, causing possible F5 damage, and killing four people. Additionally, a high-end F3 obliterated a farm in Gregory County, South Dakota, and may have been an F4 as well. Many of the individual tornadoes on May 8 moved north and northwest, an unusual trajectory for supercells in this part of the Great Plains. Many of the long-tracked tornadoes on this date, rather than single tornadoes, were probably tornado families like the two long-lived F4s.

Meteorological synopsis

A tornado over Minnetonka, Minnesota.

Temperatures on May 6 were in the upper 70s °F with high dew points, which was considered to be unusual for early May in Minnesota.[1] A strong low pressure area associated with an upper-level system moving in from the southwest and a nearby slow-moving cold front helped spark the storms. These storms formed as training supercells—an atmospheric phenomenon that is extremely rare in Minnesota. Because of the training, the same general areas from Sibley County through Carver and Hennepin and into northwestern Ramsey counties kept getting the brunt of these cells.[1]

Confirmed tornadoes

Outbreak death toll
State Total County County
total
Minnesota 13 Anoka 3
Carver 3
Hennepin 6
Sibley 1
Totals 13
All deaths were tornado-related
Confirmed
Total 		Confirmed
F?		 Confirmed
F0		 Confirmed
F1		 Confirmed
F2		 Confirmed
F3		 Confirmed
F4		 Confirmed
F5
72 10 14 15 22 6 8 1

May 5

List of confirmed tornadoes
F#
Location
County
Time (UTC)
Path length
Damage
Iowa
F2 Hartley to W of Sibley O'Brien, Osceola 2030 21.8 miles (35.1 km)
F4 S of Rinard to NE of Callender Calhoun, Webster 2215 9.9 miles (15.9 km) An intense tornado damaged eight farms near Farnhamville before hitting the south side of Slifer. The tornado destroyed a church and a parsonage, both of which were swept away.[5]
F4 Osage to N of Kendallville Floyd, Howard, Winneshiek 0200 41.6 miles (66.9 km) Two large farmhouses were leveled 3 miles (4.8 km) northwest of Kendallville, and about 28 farms were destroyed. All 11 injuries occurred in Mitchell County. The tornado was probably a family of several tornadoes, and it may have been continuous with the F3 tornado near Harmony, Minnesota, listed farther below.[5]
South Dakota
F1 Near Elkton Brookings 2045 34.7 miles (55.8 km) Three farms were reported damaged.[6]
North Dakota
F? W of Leal Barnes 2100 unknown Brief touchdown.[6]
F2 NE of Leonard to NW of Harwood Cass 2315 33.8 miles (54.4 km) This tornado family moved erratically northward, destroying barns, sheds, and other farm buildings. Seven farms were hit. At least two separate tornadoes, two hours apart, may have produced damage.[5]
Texas
F0 W of Spofford Kinney 2300 0.1 miles (0.16 km)
F1 NE of Wingate Runnels, Taylor 0300 0.1 miles (0.16 km)
Minnesota
F1 SE of Sauk Centre Stearns 2320 0.5 miles (0.80 km)
F2 NW of Alexandria to NW of Wolf Lake Douglas, Otter Tail, Becker 2330 24.3 miles (39.1 km) A tornado destroyed lakeside cottages near Lake Darling and badly damaged structures on eight farms as well. The tornado continued on to Big Toad Lake, where it destroyed a large, two-story "summer home." Five other homes and cottages sustained minor damage. A family of two separate tornadoes may have been involved.[5]
F1 S of Gaylord to E of New Auburn Sibley 2345 11.2 miles (18.0 km)
F3 S of Harmony to SE of Melrose, WI Fillmore, Houston, Winona, La Crosse (WI) 0100 65.2 miles (104.9 km) This tornado may have consisted of two separate tornadoes, with the path of the first ending, and the second beginning, in Houston County. Homes and barns were reported destroyed near Canton, Lenora, and Newburg. Farther along the path, more barns and a brick schoolhouse were also destroyed. As the tornado crossed into Wisconsin, it destroyed more buildings on several farms. A car in Wisconsin was moved 75 feet (23 m) as well.[5]
F0 SE of Elgin Wabasha 0225 0.3 miles (0.48 km)
F0 NW of Rushford Village Winona 0300 0.2 miles (0.32 km) A brief tornado destroyed two farms near Fremont. Rating disputed, ranked F2 by Grazulis.[5]
F2 W of Le Roy to NE of Racine Mower, Fillmore 0304 23.6 miles (38.0 km) A tornado destroyed a barn and damaged 20 farms in its path.[5]
Wisconsin
F2 W of Grantsburg to W of Webster Burnett 0215 14.3 miles (23.0 km)
F2 NW of Cumberland to S of Barronett Barron 0530 4.5 miles (7.2 km)
Source: National Climatic Database Center

May 6

List of confirmed tornadoes
F#
Location
County
Time (UTC)
Path length
Damage
Minnesota
F4 NE of Cologne to N of Crystal Bay Carver 0008 13 miles (21 km) 3 deaths – The first of four powerful F4 tornadoes touched down just east of Cologne in Carver County. The tornado struck the Island Park–Mound area, where it destroyed 17 homes,[5] some of which were leveled. The tornado then struck and destroyed most of the Navarre community, where 16 homes were destroyed. The tornado also destroyed all barns and outbuildings on 30 farms. Homes were destroyed on 20 farms as well.[5] According to a 1975 map, which contains the most revised data on the May 6 tornadoes, the tornado dissipated north of Crystal Bay.[4]
F4 Chanhassen to S of Wayzata Carver 0027 7 miles (11 km) The second of the four F4 tornadoes—and the first of two to be photographed this day—touched down near Lake Susan in Chanhassen and traveled 7 miles (11 km) toward Deephaven in Hennepin County. The first damage was reported south of Chanhassen, where 30 homes were damaged or destroyed. The tornado traveled due north, causing damage to a lumberyard and a shopping center. The tornado then damaged 35 homes at Lotus Lake and damaged or destroyed another 50 at Christmas Lake. As the tornado continued into Deephaven, it destroyed 100 homes, some of which were completely leveled, including "large and expensive" homes.[5] According to official sources, the tornado dissipated after hitting Deephaven, and only two tornadoes hit Fridley;[4] however, Grazulis reports that the tornado turned northeast, continuing beyond Deephaven, passing just south of Medicine Lake, striking Golden Valley, and hitting Fridley at 7:10 p.m. (0110 UTC).[5] Six homes were reportedly damaged in Golden Valley, "clocks stopped" in Fridley, and 25 airplanes were damaged or destroyed at Anoka County-Blaine Airport in Blaine.[5] However, the official records end this tornado near Deephaven and only indicate that two tornadoes, not three, hit Fridley.[4]
F3 E of New Auburn to NW of Lester Prairie Sibley 0034 16 miles (26 km) Tornado touched down about 3 mi (4.8 km) east of New Auburn in Sibley County and moved to just west of Lester Prairie in McLeod County. The tornado damaged or destroyed at least 25 farm buildings, as well as a church and a school, but there were no injuries or fatalities. Damages reached $1,000,000 (1965 USD).[5]
F2 E of Green Isle to NE of Norwood Young America Sibley 0043 11 miles (18 km) 1 death – Tornado touched down about 2 mi (3.2 km) east of Green Isle in Sibley County and was on the ground 11 mi (18 km). It dissipated about 2 mi (3.2 km) southwest of Waconia in Carver County. A farmer and his cattle were killed 3 mi (4.8 km) southeast of Hamburg.[5] Photographs showed that nearby trees were debarked and shredded.[7] The tornado was up to .75 mi (1.21 km) wide near Norwood Young America and Waconia.[5] Three barns were reportedly destroyed southwest of Cologne at 7:15 p.m. (0115 UTC), but Grazulis counts the damage as being related to a second F2 tornado (not officially listed).[5]
F4 SW of Columbia Heights to Fridley to N of Spring Lake Park Hennepin,[5] Anoka 0106 7 miles (11 km) 3 deaths – The first of at least two tornadoes to hit Fridley touched down in the southwesternmost corner of Fridley in Anoka County. It then moved across the Northern Ordnance industrial plant and continued to Osborne Road and Highway 65.[5][7] At this point, the tornado was visually spectacular and, like the Deephaven tornado, was one of the two tornadoes to be photographed during the outbreak.[5][7] The funnel then struck Fridley directly, hitting the main school and park complex, the city hall, and a trailer court.[5][7] 300 people were attending an evening program in Fridley Junior High when the tornado struck, but only a single child was injured.[5] The tornado eventually struck hundreds of homes in Fridley before continuing north-northeast into Spring Lake Park. There, the tornado was at its greatest intensity, destroying 150 homes and leveling some of them.[5] 75% of all the businesses in Spring Lake Park were reported destroyed, and 900 people in the town were said to be homeless.[5] 175 people were injured. The tornado dissipated just northeast of Laddie Lake in Blaine in Anoka County.[7]
F4 Golden Valley to Fridley to Lino Lakes Hennepin, Anoka, Ramsey[8] 0214 18 miles (29 km) 6 deaths – The last and deadliest violent tornado of the day touched down in Golden Valley in Hennepin County and moved across north Minneapolis, Fridley in Anoka County, and Mounds View in Ramsey County before dissipating just west of Centerville in Anoka County. Like the previous event, this tornado also struck the Northern Ordnance industrial plant. Total damage from the two tornadoes at the Northern Ordnance plant reached $2 million (1965 USD) in damage, shutting down the plant for more than one month.[7] Next, the tornado damaged 25 homes and eight businesses when it hit Golden Valley.[8] The tornado then became the second of the day to hit Fridley, and even struck the same trailer park in Fridley hit by the previous tornado.[7][8] The tornado also destroyed 85% of an elementary school. In Fridley, some homes were hit more than once by multiple tornadoes.[8] As it continued into Mounds View, the tornado completely leveled numerous homes, killing six people. In all, 46 homes in Mounds View were destroyed, and losses reached about $1 million (1965 USD).[8] 158 people were injured.
Oklahoma
F2 NW of Loyal Kingfisher 0000 0.1 miles (0.16 km) A brief touchdown destroyed a barn, a shop, a granary, and a shed. It also damaged four homes and two "combines."[5]
F2 SE of Dodson, TX, to W of Granite, OK Harmon, Greer 0050 31.3 miles (50.4 km) This tornado may have begun in Texas. It damaged or destroyed at least six homes, 10 barns, a gin, a store, a church, and a school.[5]
F1 SE of Canton Blaine 0100 0.1 miles (0.16 km)
F0 Oakwood Dewey 0100 0.1 miles (0.16 km)
F1 Dewey Washington 0300 0.1 miles (0.16 km)
Nebraska
F0 E of Newcastle Dixon 0145 0.1 miles (0.16 km)
Source: National Climatic Database Center

May 7

List of confirmed tornadoes
F#
Location
County
Time (UTC)
Path length
Damage
Wisconsin
F2 S of Shell Lake Washburn 1430 1 mile (1.6 km) A brief tornado unroofed a school in which 300 students sheltered, but none were hurt.[8]
South Dakota
F? NE of Lake Andes Charles Mix 1830 unknown
Iowa
F? Oelwein Fayette 1855 unknown
F? Fairfield Van Buren 2030 unknown
Kansas
F0 S of Garden City Finney 2200 0.1 miles (0.16 km)
F2 N of Pierceville Finney 2200 0.1 miles (0.16 km)
F2 N of Cimarron Finney 2200 0.1 miles (0.16 km)
Minnesota
F0 SW of Kenyon Le Seur 0010 0.5 miles (0.80 km)
Oklahoma
F0 Arnett Ellis 0050 0.8 miles (1.3 km)
Texas
F0 S of Wheeler Wheeler 0050 0.1 miles (0.16 km)
Source: National Climatic Database Center

May 8

List of confirmed tornadoes
F#
Location
County
Time (UTC)
Path length
Damage
Colorado
F2 N of Nunn Weld 0900 1 mile (1.6 km) A brief touchdown caused damage to farm structures, equipment, and trees.[6]
Wisconsin
F1 N of Waukesha Waukesha 1915 2 miles (3.2 km)
Oklahoma
F0 SE of Randlett Cotton 2000 0.1 miles (0.16 km)
F1 SW of Barnsdall Osage 2200 0.1 miles (0.16 km)
F1 N of Stidham McIntosh 0300 0.1 miles (0.16 km)
F0 S of Marietta Love 0310 0.1 miles (0.16 km)
Kansas
F? SW of Independence Montgomery 2115 1 mile (1.6 km) A tornado caused $4,000 (1965 USD) in damage near the Independence Municipal Airport.[6]
F? N of Girard Crawford 2315 unknown Brief touchdown.[6]
Nebraska
F3 N of Saint Michael to SW of Farwell Howard 2200 10.2 miles (16.4 km) A tornado unroofed some homes and barns and passed northwest of Boelus.[8]
F4 NW of Farwell to Orchard Howard, Greeley, Wheeler, Antelope, 2225 78.9 miles (127.0 km) This long-tracked tornado was likely a family of multiple violent tornadoes. The tornado destroyed numerous farms, many of which were entirely leveled. Two people sheltering in a basement north of Greeley may have been injured,[8] but these injuries are not listed officially.
F2 SE of Long Pine to NW of Mills Rock, Keya Paha 2230 44.9 miles (72.3 km) A long-lived tornado leveled a farmhouse and may have injured a man fleeing in a pickup truck. The tornado also destroyed buildings on "at least a dozen" farms northwest of Newport. This event may have been two separate tornadoes, one 4 mi (6.4 km) east of Bassett and another northwest of Newport. Rating disputed, ranked F3 by Grazulis.[8]
F2 E of Johnstown Brown, Keya Paha 2230[8] 9 miles (14 km) A strong tornado destroyed three homes on at least seven ranches, along with other structures. Vehicles were thrown up to .5 mi (0.80 km) from where they originated. According to Grazulis, this tornado caused near-F4 damage to ranches 6 mi (9.7 km) northwest of Ainsworth,[8] though the official rating is only F2. The tornado may have stayed on the ground as far as Wewela, South Dakota, and the parent storm eventually produced an F5 tornado near Colome in South Dakota.[8]
F3 Hebron to E of Cordova Thayer, Fillmore, Saline, Seward 2240 40.1 miles (64.5 km) A long-lived tornado leveled a barn 3 mi (4.8 km) east of Ohiowa.[8] Several farms were reportedly destroyed as well.[6]
F3 SW of Chambers to Saratoga Holt 2300 44.8 miles (72.1 km) A long-tracked tornado destroyed and swept away many barns. A car was thrown 200 yd (180 m), and ranches were completely destroyed.[8]
F1 Stapleton to S of Valentine Logan, Thomas, Cherry 2300 89.8 miles (144.5 km) A long-lived tornado did "major damage" near Thedford,[6] destroying at least one barn.[8] Rating disputed, ranked F2 by Grazulis.
F1 N of Eagle Cass 2300 0.1 miles (0.16 km) Brief touchdown reported.[6]
F4 N of Wood River to Wausa Hall, Greeley, Boone, Antelope, Cedar 2330 125.7 miles (202.3 km) 4 deaths – This long-lived family of violent tornadoes destroyed 90% of the village of Primrose. The tornado was reported to have had two funnels as it hit Primrose.[9] Homes were swept from their foundations, and the damage swath was 300 yd (270 m) wide.[10] Tree damage in the village was severe.[11] Vehicles were thrown hundreds of yards, and there may have been F5 damage to buildings as well.[12] Cars were carried for 400 yd (370 m), and a truck body was carried and rolled for 2 mi (3.2 km).[8] 53 people were injured, and four were dead at Primrose. At least one horse was killed.
F2 E of Ainsworth Brown, Keya Paha 2330 4.1 miles (6.6 km) A tornado passed east of Ainsworth.[6]
F1 W of Hampton Hamilton 2330 0.1 miles (0.16 km) Brief touchdown occurred between Aurora and Hampton.[6]
F1 N of Phillips to NE of Chapman Hamilton 2335 7.2 miles (11.6 km) A tornado destroyed all the buildings except the farmhouse on a farm. Rating disputed, ranked F2 by Grazulis.[8]
F0 W of Spencer Boyd 0000 0.1 miles (0.16 km) Brief touchdown witnessed.[6]
F2 Columbus to W of Clarkson Platte, Colfax 0000 24 miles (39 km) A tornado skipped along and destroyed structures on several farms.[6]
F1 E of Winside to Dakota City Wayne, Dixon, Dakota 0030 41.5 miles (66.8 km) A skipping tornado caused mostly minor damage, but produced major damage to a farm northeast of Wayne.[6]
South Dakota
F? N of Fort Thompson Buffalo 2200 unknown
F5 E of Wewela to NE of Winner Tripp 2315 30.1 miles (48.4 km) See section on this tornado. This huge tornado, about 1 mi (1.6 km) wide, damaged 25 farms, destroyed seven farms, and completely swept away three of them near Gregory.[8][12]
F2 SW of Colome Tripp 2323 0.1 miles (0.16 km)
F3 SW of Burke Gregory 0000 1.5 miles (2.4 km) A brief tornado moved northwest and destroyed all buildings on a farm, including two homes, a concrete barn, and a wooden barn. Vehicles and machinery were mangled into unrecognizable shapes. Rating disputed, ranked F4 by Grazulis.[8]
F2 SE of Howard Miner 0030 3.3 miles (5.3 km) Moved northwest, north of Canova. Some farm structures were damaged, and cattle were killed.[6]
F1 SE of Onida Sully 0030 0.1 miles (0.16 km)
F2 W of Baltic to NE of Colton Clay 0100 4.5 miles (7.2 km) Barns and concrete silos were destroyed on three farms.[8]
F2 SW of Pukwana Brule 0100 4.3 miles (6.9 km) A tornado moved northwest, destroying newly built barns on two farms, along with several silos.[8]
F0 NW of Gettysburg Potter 0100 0.1 miles (0.16 km) Brief touchdown over open country.[6]
F? NW of Oahe Dam Stanley 0200 unknown
F0 SW of Akaska Potter 0332 0.1 miles (0.16 km)
F? SE of Timber Lake Dewey 0425 unknown
F? SW of Mobridge Corson 0435 unknown
Arkansas
F2 SE of Fort Smith 0230 Sebastian 5.1 miles (8.2 km) A tornado destroyed motel cabins and tore roofs and walls from homes. Business buildings sustained damage on seven farms.[8]
Source: National Climatic Database Center

Notable tornadoes

Fridley, Minnesota (two tornadoes)

Tornado damage in Fridley, Minnesota.

Two tornadoes touched down in Fridley, just over an hour apart. In all, six people were killed in the Fridley tornadoes and over 180 were injured. Over 450 homes were destroyed in Fridley, and neighboring Mounds View also sustained heavy damage. A man who called WCCO radio after the first Fridley tornado claimed on air that he had been in his car when the tornado hit and that the tornado blew out his car windows. Although he is widely believed to have been killed by the second Fridley twister later that night (which did kill a 26-year-old man with a similar name), the caller was actually a teacher at Fridley Junior High School who survived. The tornado also damaged the sign adorning the Heights Theater in Columbia Heights. In all, both Fridley tornadoes damaged 1,100 homes and destroyed about 425; total losses reached $14.5 million, $5 million of which was to the Fridley school system.[2][5] Photographs for the earlier Deephaven and second Fridley tornado were published in the Minneapolis Tribune (now Star Tribune) newspaper. Early radar images showed the supercells as they moved through the area.[2]

Gregory, South Dakota

On May 8th, an F5 tornado tore through the town of Gregory, South Dakota, and became the only tornado to be rated as such in South Dakota's history. On the ground for around 30 miles, the tornado reached a mile wide and destroyed 7 farms, 3 of which were swept away. Fortunately, it resulted in no deaths.

Aftermath

The outbreak in Minnesota on May 6 was voted a tie by the Minnesota Climatology Office for the "fifth most significant Minnesota Weather Event of the 20th Century" with the 1965 Mississippi & Minnesota River Flooding.[13] Considering this outbreak occurred just three weeks after the Palm Sunday tornado outbreak, quick and successful warnings from the U.S. Weather Bureau and transmission from WCCO Radio kept the death toll relatively low. This was also the first time in Minnesota state history where civil defense sirens were used for severe weather purposes.[2]

See also

References

  1. 1 2 3 4 Lattery, Robert. "Six Deadly Twisters". Archived from the original on 2012-02-24. Retrieved 18 December 2013.
  2. 1 2 3 4 "Summary of May 6, 1965 Tornado Outbreak". Chanhassen, Minnesota: National Weather Service. Retrieved 18 December 2013.
  3. ↑ Schneider, Russell S.; Harold E. Brooks; Joseph T. Schaefer. "Tornado Outbreak Day Sequences: Historic Events and Climatology (1875-2003)" (PDF). Norman, Oklahoma: Storm Prediction Center. Retrieved 13 February 2013.
  4. 1 2 3 4 Kuehnast, E. L.; Baker, D. G.; Enz, J. W. (1975). Climate of Minnesota, Part VIII -- Precipitation Patterns in the Minneapolis–St. Paul Metropolitan Area and Surrounding Counties (Technical report). University of Minnesota. 301.
  5. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Grazulis, Significant Tornadoes, 1073.
  6. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 "Storm Data and Unusual Weather Phenomena". Storm Data (Asheville, North Carolina: United States Department of Commerce) 7 (5). May 1965.
  7. 1 2 3 4 5 6 7 "The May 6, 1965 Tornadoes". NWS Twin Cities. NOAA. May 13, 2013. Retrieved 23 December 2013.
  8. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 Grazulis, Significant Tornadoes, 1074.
  9. ↑ "Tornadoes belt Nebraska". The Tuscaloosa News. The Associated Press. May 9, 1965. Retrieved 25 November 2013.
  10. ↑ "Four Dead In Twister". Daytona Beach Sunday News-Journal. The Associated Press. May 10, 1965. Retrieved 25 November 2013.
  11. ↑ "Tornado Death Toll Reaches 4 At Primrose". Lewiston Morning Tribune. The Associated Press. May 10, 1965. Retrieved 25 November 2013.
  12. 1 2 Grazulis, Thomas P. (2001). F5-F6 Tornadoes. St. Johnsbury, VT: The Tornado Project.
  13. ↑ "Significant Minnesota Weather Events of the 20th Century". St. Paul, Minnesota: Minnesota Climatology Working Group. Retrieved 18 December 2013.

Bibliography

Notes

  1. ↑ 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) modern records that began in 1950, is defined as, at most, two (one) consecutive days without at least one significant (F2 or stronger) tornado.[3]
  2. ↑ All damage totals are in 1965 United States dollars unless otherwise noted.

External links

This article is issued from Wikipedia - version of the Sunday, April 03, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.