1965 Palm Sunday tornado outbreak

This article is about the 1965 tornado outbreak. For other uses, see Palm Sunday tornado outbreak (disambiguation).
1965 Palm Sunday tornado outbreak
Two greyish tornado funnels silhouetted against a pale sky on either side of a road behind telephone poles
The F4 tornado that struck Midway, Indiana, between Goshen and Dunlap
This image has been nominated for deletion as a potential copyright violation.
TypeTornado outbreak
DurationApril 10–12, 1965
Highest gust80 mph (130 km/h) at three locations on April 11[1]
Tornadoes
confirmed		55 confirmed
Max. rating1F4 tornado
Duration of
tornado outbreak2		1 day and 16 hours
Largest hail2 in (5.1 cm) at seven locations on April 10–12[2]
Fatalities266 fatalities, 3,662 injuries
Damage$1.217 billion (1965 USD)[nb 1][3]
$11.8 billion (2024 USD)
Areas affectedSouthern and Midwestern United States (Upland South, Driftless Area, and Great Lakes region, primarily Indiana, Ohio, and Michigan)

1Most severe tornado damage; see Fujita scale
2Time from first tornado to last tornado

On April 10–12, 1965, a historic severe weather event affected the Midwestern and Southeastern United States. The tornado outbreak produced 55 confirmed tornadoes in one day and 16 hours. The worst part of the outbreak occurred during the afternoon hours of April 11 into the overnight hours going into April 12. The second-largest tornado outbreak on record at the time, this deadly series of tornadoes, which became known as the 1965 Palm Sunday tornado outbreak, inflicted a swath of destruction from Cedar County, Iowa, to Cuyahoga County, Ohio, and a swath 450 miles long (724 km) from Kent County, Michigan, to Montgomery County, Indiana. The main part of the outbreak lasted 16 hours and 35 minutes and is among the most intense outbreaks, in terms of tornado strength, ever recorded, including at least four "double/twin funnel" tornadoes. In all, the outbreak killed 266 people, injured 3,662 others, and caused $1.217 billion (1965 USD) in damage.[nb 2][nb 3][nb 4] In 2023, tornado expert Thomas P. Grazulis created the outbreak intensity score (OIS) as a way to rank various tornado outbreaks. The 1965 Palm Sunday tornado outbreak received an OIS of 238, making it the fourth worst tornado outbreak in recorded history.[13]

  1. ^ Storm Data Publication 1965, Events reported between 04/10/1965 and 04/12/1965 (3 days)
  2. ^ Storm Data Publication 1965, Events reported between 04/10/1965 and 04/12/1965 (3 days)
  3. ^ Storm Data Publication 1965, Events reported between 04/10/1965 and 04/12/1965 (3 days)
  4. ^ Schneider, Russell S.; Brooks, Harold E.; Schaefer, Joseph T. (2004). Tornado Outbreak Day Sequences: Historic Events and Climatology (1875–2003) (PDF). 22nd Conf. Severe Local Storms. Hyannis, Massachusetts: American Meteorological Society. Retrieved September 17, 2019.
  5. ^ Grazulis 1993, p. 141.
  6. ^ Grazulis 2001a, p. 131.
  7. ^ Edwards, Roger (March 5, 2015). "Enhanced F Scale for Tornado Damage". The Online Tornado FAQ (by Roger Edwards, SPC). Storm Prediction Center. Retrieved February 25, 2016.
  8. ^ "Enhanced Fujita Scale (EF-Scale)". Environment and Climate Change Canada. June 6, 2013. Archived from the original on March 3, 2016. Retrieved February 25, 2016.
  9. ^ "The International Tornado Intensity Scale". Tornado and Storm Research Organisation. 2016. Archived from the original on March 5, 2016. Retrieved February 25, 2016.
  10. ^ Grazulis 2001a, pp. 251–4.
  11. ^ Edwards, Roger (March 5, 2015). "The Online Tornado FAQ (by Roger Edwards, SPC)". Storm Prediction Center: Frequently Asked Questions about Tornadoes. Storm Prediction Center. Retrieved February 25, 2016.
  12. ^ Cook & Schaefer 2008, p. 3135.
  13. ^ Grazulis, Thomas P. (2023). Significant Tornadoes 1974–2022. St. Johnsbury, Vermont: The Tornado Project. p. 637. ISBN 978-1-879362-01-7.


Cite error: There are <ref group=nb> tags on this page, but the references will not show without a {{reflist|group=nb}} template (see the help page).