165:
103:
45:
184:, in which 148 tornadoes were counted. Both occurred within the United States and Canada. The total number of tornadoes is a problematic method of comparing outbreaks from different periods, however, as many more weaker tornadoes, but not stronger tornadoes, are reported in the US in recent decades than in previous ones due to improvements in tornado detection.
250:
Tornado outbreak sequences tend to dominate the tornado statistics for a year and often cause a spike in tornado numbers for the entire year. Not all periods of active tornado occurrences are outbreak sequences, there must be no break in the activity to satisfy the definition. Active periods occur
144:
The tornadoes usually occur within the same day or continue into the early morning hours of the succeeding day, and within the same region. Most definitions allow for a break in tornado activity (time elapsed from the end of the last tornado to the beginning of the next tornado) of six hours. If
251:
ranging from every year to every several years whereas continuously active periods are less common and can be rare depending on the parameters applied to define a sequence. By the late 2010s, medium to long range
161:. Tornado outbreaks can also occur during other times of the year and in other parts of the world. A secondary less active and annually inconsistent tornado "season" in the U.S. occurs in late autumn.
906:
145:
tornado activity indeed resumes after such a lull, many definitions consider the event to be a new outbreak. A series of continuous or nearly continuous tornado outbreak days is a
782:
Mercer, Andrew E.; C.M. Shafer; C.A. Doswell III; L.M. Leslie; M.B. Richman (December 2009). "Objective
Classification of Tornadic and Nontornadic Severe Weather Outbreaks".
684:
164:
289:
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weather system. The number of tornadoes required to qualify as an outbreak typically are at least six to ten, with at least two rotational locations (if
111:
240:
232:
55:
255:
advanced sufficiently that some periods of high tornado activity can be somewhat reliably predicted several days to several weeks in advance.
216:
168:
A timeline showing three day sequences with at least four violent tornadoes and the number of deaths associated with each. (1875–2014)
17:
264:
220:
711:; R. Edwards; R.L. Thompson; J.A. Hart; K.C. Crosbie (2006). "A Simple and Flexible Method for Ranking Severe Weather Events".
599:
331:
299:
244:
208:
activity consisting of a series of tornado outbreaks over multiple days with no or very few days lacking tornado outbreaks.
434:"Quantifying uncertainty and variable sensitivity within the US billion-dollar weather and climate disaster cost estimates"
513:
Hamill, Thomas M.; R.S. Schneider; H.E. Brooks; G.S. Forbes; H.B. Bluestein; M. Steinberg; D. Meléndez; R.M. Dole (2005).
236:
228:
89:
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665:
376:
351:
212:
750:
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Fuhrmann, Christopher M.; C. E. Konrad II; M. M. Kovach; J. T. McLeod; W. G. Schmitz; P. G. Dixon (2014).
860:"On the use of areal coverage of parameters favorable for severe weather to discriminate major outbreaks"
1012:
1007:
126:
146:
804:
754:
733:
414:
395:
770:
269:
154:
71:
149:. In the United States and Canada, tornado outbreaks usually occur from March through June in the
986:
843:"Using kernel density estimation to identify, rank, and classify severe weather outbreak events"
627:"Ranking of Tornado Outbreaks across the United States and Their Climatological Characteristics"
799:
728:
685:
Scientists forecasted late May tornado outbreak nearly four weeks before it ripped through U.S.
487:
893:
67:
951:
918:
876:
859:
842:
791:
720:
641:
567:
526:
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832:(1979). "The Climatology and Synoptic Meteorology of Southern Plains' Tornado Outbreaks".
63:
8:
708:
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181:
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571:
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491:
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367:
817:
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595:
469:
319:
766:
492:"Small Sample Size and Data Quality Issues Illustrated Using Tornado Occurrence Data"
473:
461:
433:
327:
295:
180:, with 362 tornadoes and about $ 10 billion in direct damages. It surpassed the
821:
755:"Proposals for modernizing definitions of tornado and severe thunderstorm outbreaks"
661:
1002:
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809:
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371:
347:
107:
33:
624:
138:
580:
555:
457:
996:
964:
939:
894:"The Destruction Potential Index – a method for comparing tornado days (DPI)"
653:
465:
396:"Tornado Outbreak Day Sequences: historic events and climatology (1875-2003)"
158:
781:
157:, and the Southeastern United States in an area colloquially referred to as
982:
877:"A Multivariate Index for Ranking and Classifying Severe Weather Outbreaks"
150:
102:
813:
539:
514:
512:
904:
829:
749:
130:
415:"Tornado Outbreak Days: an updated and expanded climatology (1875-2003)"
54:
deal primarily with the United States and Canada and do not represent a
707:
940:"On the Significance of Multiple Consecutive Days of Tornado Activity"
905:
Verbout, Stephanie M.; H.E. Brooks; L.M. Leslie; D.M. Schultz (2006).
930:
742:
134:
324:
Significant
Tornadoes 1680-1991: A Chronology and Analysis of Events
857:
412:
235:. Another exceptional outbreak sequence apparently occurred during
393:
326:. St. Johnsbury, VT: The Tornado Project of Environmental Films.
205:
122:
753:; R. L. Thompson; C. Crosbie; J. A. Hart; C. A. Doswell (2004).
394:
Schneider, Russell; H.E. Brooks; J.T. Schaefer (October 2004).
239:. Although some days lacked tornado outbreaks, the period from
377:
10.1175/1520-0493(1977)105<0477:SCAOTO>2.0.CO;2
771:"Meteorological aspects of high-impact tornado outbreaks"
413:
Schneider, Russell; H. E. Brooks; J. T. Schaefer (2004).
858:
Shafer, Chad; C. Doswell; L. Leslie; M. Richman (2010).
775:
Symposium on the
Challenges of Severe Convective Storms
556:"Supplement to: The May 2003 Extended Tornado Outbreak"
247:
also were periods of especially high tornado activity.
27:
Multiple tornadoes spawned from the same weather system
204:, is a period of continuous or nearly continuous high
907:"Evolution of the U.S. Tornado Database: 1954-2003"
900:. Minneapolis, MN: American Meteorological Society.
891:
874:
594:
432:Smith, Adam B.; Matthews, Jessica L. (July 2015).
352:"Some Climatological Aspects of Tornado Outbreaks"
703:. NOAA-NWS-NCEP Storm Prediction Center (poster).
294:(2nd ed.). American Meteorological Society.
211:Major tornado outbreak sequences occurred in the
176:. The largest tornado outbreak on record was the
994:
840:
777:. Atlanta, GA: American Meteorological Society.
761:. Hyannis, MA: American Meteorological Society.
588:
421:. Hyannis, MA: American Meteorological Society.
402:. Hyannis, MA: American Meteorological Society.
701:"Noteworthy North American Tornado Outbreaks"
431:
52:The examples and perspective in this article
187:
892:Thompson, Richard L.; M.D. Vescio (1998).
680:
678:
172:Very large tornado outbreaks are known as
963:
803:
732:
579:
547:
538:
375:
90:Learn how and when to remove this message
515:"The May 2003 Extended Tornado Outbreak"
318:
287:
265:Lists of tornadoes and tornado outbreaks
163:
101:
698:
675:
486:
14:
995:
983:US Violent Tornado Outbreak Statistics
898:19th Conference on Severe Local Storms
828:
765:
759:22nd Conference on Severe Local Storms
553:
506:
419:22nd Conference on Severe Local Storms
346:
937:
836:. Norman, OK: University of Oklahoma.
602:. The Tornado Project. Archived from
406:
389:
387:
340:
312:
38:
875:Shafer, Chad; C.A. Doswell (2010).
24:
692:
554:Hamill, T.M.; et al. (2005).
384:
110:that caused a tornado outbreak on
25:
1024:
976:
881:Electron. J. Sev. Storms Meteorol
864:Electron. J. Sev. Storms Meteorol
847:Electron. J. Sev. Storms Meteorol
841:Shafer, Chad; C. Doswell (2011).
496:Electron. J. Sev. Storms Meteorol
43:
618:
288:Glickman, Todd S., ed. (2000).
480:
425:
400:22nd Conf. Severe Local Storms
281:
200:, sometimes referred to as an
121:is the occurrence of multiple
13:
1:
275:
198:tornado outbreak day sequence
7:
258:
66:, discuss the issue on the
10:
1029:
106:Dozens of supercells over
31:
938:Trapp, Robert J. (2014).
699:Corfidi, Stephen (2013).
581:10.1175/BAMS-86-4-HamillA
458:10.1007/s11069-015-1678-x
202:extended tornado outbreak
194:tornado outbreak sequence
188:Tornado outbreak sequence
147:tornado outbreak sequence
18:Tornado outbreak sequence
965:10.1175/MWR-D-13-00347.1
654:10.1175/WAF-D-13-00128.1
270:Outbreak intensity score
155:Midwestern United States
32:For the video game, see
709:Doswell, Charles A. III
560:Bull. Am. Meteorol. Soc
519:Bull. Am. Meteorol. Soc
488:Doswell, Charles A. III
291:Glossary of Meteorology
241:mid to late April 2011
169:
114:
814:10.1175/2009MWR2897.1
540:10.1175/BAMS-86-4-531
167:
105:
671:on 18 February 2019.
237:mid to late May 1896
125:spawned by the same
72:create a new article
64:improve this article
956:2014MWRv..142.1452T
923:2006WtFor..21...86V
796:2009MWRv..137.4355M
725:2006WtFor..21..939D
646:2014WtFor..29..684F
606:on 26 February 2014
572:2005BAMS...86S...3H
531:2005BAMS...86..531H
450:2015NatHa..77.1829S
368:1977MWRv..105..477G
320:Grazulis, Thomas P.
182:1974 Super Outbreak
178:2011 Super Outbreak
767:Forbes, Gregory S.
598:; Doris Grazulis.
170:
139:multiple tornadoes
133:) or at least two
115:
1013:Natural disasters
1008:Tornado outbreaks
348:Galway, Joseph G.
333:978-1-879362-03-1
301:978-1-878220-34-9
100:
99:
92:
74:, as appropriate.
16:(Redirected from
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931:10.1175/WAF910.1
911:Weather Forecast
901:
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743:10.1175/WAF959.1
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713:Weather Forecast
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664:. Archived from
634:Weather Forecast
631:
622:
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600:"1896 Tornadoes"
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444:(3): 1829–1851.
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356:Mon. Weather Rev
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304:. Archived from
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119:tornado outbreak
108:Northern Arizona
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34:Tornado Outbreak
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830:Moller, Alan R.
805:10.1.1.736.9711
790:(12): 4355–68.
734:10.1.1.529.5483
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693:Further reading
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566:(4): ES3–ES16.
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438:Natural Hazards
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174:super outbreaks
112:October 6, 2010
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604:the original
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151:Great Plains
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80:October 2019
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834:M.S. Thesis
253:forecasting
131:squall line
997:Categories
502:(5): 1–16.
276:References
137:producing
135:supercells
800:CiteSeerX
729:CiteSeerX
474:129795283
466:0921-030X
123:tornadoes
68:talk page
822:15831045
769:(2006).
662:56010947
490:(2007).
350:(1977).
322:(1993).
259:See also
62:You may
1003:Tornado
952:Bibcode
919:Bibcode
792:Bibcode
721:Bibcode
642:Bibcode
568:Bibcode
527:Bibcode
446:Bibcode
364:Bibcode
215:in May
206:tornado
820:
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330:
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231:, and
153:, the
818:S2CID
669:(PDF)
658:S2CID
630:(PDF)
610:8 May
470:S2CID
196:, or
70:, or
887:(1).
870:(7).
853:(2).
612:2008
462:ISSN
328:ISBN
296:ISBN
243:and
233:2011
229:2003
225:1974
221:1965
217:1917
987:SPC
960:doi
948:142
927:doi
810:doi
788:137
739:doi
650:doi
576:doi
535:doi
454:doi
372:doi
360:105
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