Saturday 5 May 2012

Deadliest Tornado's

By Christopher C. Burt
Published: 8:52 PM GMT on May 03, 2012

DEADLIEST TORNADOS

On April 6, 2011 I posted a blog about the “world’s deadliest tornados”. I had no idea that just three weeks later one of the world’s deadliest tornado outbreaks would occur on April 27th. Then on May 22nd Joplin, Missouri was hit by one of the single deadliest tornados on record leading 2011 to become the 2nd deadliest tornado year in U.S. records. This weak, May 3-10, is historically the most active weak for tornados in the U.S.A., so I thought this might be a good time to look back at what the deadliest tornadoes on record have been, not just in the U.S.A., but the world as well. So far this year (2012 as of May 3rd) there have been 63 tornado-related fatalities in the U.S., quite a bit above the long-term average for such at this date and mostly as a result of the twister outbreak of March 2nd in the Ohio Valley.


A map illustrating the regions of the U.S. that have recorded significant (EF-3 or stronger) tornados. The vast majority of tornado-related fatalities occur during the storms designated as ‘violent’ (EF-4 or EF-5 strength. Map from wunderground.com

The United States and Canada are the only countries in the world to have verified reports of the most violent tornadoes: those with a classification of F-5 or EF-5 (wind speeds estimated to be in excess of 260mph/417kph and measured as high as 318mph/512kph on the old Fujita Scale or over 200mph/320kph on the new Enhanced Fujita scale). See this link for the details about the Fujita and Enhanced Fujita Scales and the differences between the two.

Since 1900 there have only been a total of 103 such storms, all but one in the United States. In all but 10 cases these storms resulted in fatalities. This table (originally from my book Extreme Weather: A Guide and Record Book) represents all the known F-5 or EF-5 tornado events in the world since 1900-2006. The table following this lists the EF-5 tornados that have occurred since the new designation took effect in 2007:




A F-5 tornado completely swept away the town of Glazier, Texas on April 9, 1947. The same tornado killed 181 in Woodward, Oklahoma (see table above) and so ranks as the 6th deadliest tornado in U.S. history.. Photo courtesy of the ‘Amarillo Globe-News’.

The reason the heart of the North American continent bears the brunt of these most powerful of twisters lies with its unique topography. Only in North America does a solid land mass stretch from the sub-tropics to the arctic with no mountain barriers to inhibit the mixture of air masses originating from these two regions.

THE DEADLIEST SINGLE TORNADOES, TORNADO OUTBREAKS, AND TORNADO YEARS IN U.S. HISTORY

The ‘single’ deadliest tornado in U.S. history was the famous ‘Tri-state’ twister of March 25, 1925 when 695 died in Missouri, Illinois, and Indiana when a F-5 mile-wide monster carved a course some 219 miles through the three states. However, modern research suggests that this may well have been a series (or at least two) tornadoes developing from a single super cell traversing the area. Eight other violent (F-2 or stronger) tornadoes killed an additional 52 people in Alabama, Tennessee, and Kentucky over the course of the day bringing the total killed to 747 and making this also the deadliest tornado outbreak in American history.


Griffin, Indiana lies devastated following the passage of the Tri-state tornado on March 18, 1925. 71 people perished in the vicinity of Griffin. Photo from the National Archives.

The 2nd deadliest single tornado was that which struck Natchez, Mississippi on May 7, 1840 killing 317, many of the fatalities being along the town’s waterfront when the twister traversed the Mississippi River. The 2nd deadliest tornado outbreak was that of April 5-6, 1936 when 454 were killed across the Southeast from Arkansas to South Carolina. Tupelo, Mississippi was the worst affected where 216 were killed by a tornado on March 5th and Gainesville, Georgia where 203 lost their lives the following day. The April 27, 2011 event was the 4th deadliest on record and the Joplin, Missouri tornado of May 22, 2011 the 7th deadliest single tornado in U.S. history with 161 fatalities.


A map showing the tracks of the EF-4 and EF-5 tornados that ripped across the Southeast on April 27, 2011 killing 325. Map by Katie Wheatley based on Storm Prediction Center data.

Below are tables listing the 10 deadliest U.S. tornado outbreaks, 10 deadliest single tornadoes in U.S. history, and 10 deadliest years since 1875 so far as tornado fatalities in the U.S are concerned. Some of these figures are, to some degree, disputable and simply represent the best available information to date:




DEADLIEST TORNADOS AROUND THE WORLD

CANADA


Environment Canada has concluded that the tornado that formed near Elie, Manitoba on June 22, 2007 was of EF-5 strength making it the only such storm of this violent nature to occur outside of the United States. Canada’s deadliest tornado event was that of June 30, 1912 when 28 were killed in the city of Regina, Saskatchewan. More recently, 27 died in and around Edmonton, Alberta on July 31, 1987 when a F-4 slammed the city.


The second deadliest tornado in Canadian history bears down on Edmonton, Alberta on July 31, 1987. Some believe this tornado may have reached F-5 strength at one point. Twenty-seven lives were lost. Photo by Robert Carlton, University of Alberta.


Other regions of the world that also experience very violent tornadoes (EF2-4 strength) fairly regularly (but to date no EF-5s) include the following:

BANGLADESH

Bangladesh has suffered the deadliest tornadoes on record and several of these have been estimated to be in the F-4 category of strength. The reason Bangladesh receives violent tornadoes is because during the beginning of the wet monsoon season (usually April and May) cold dry air spilling south over the Himalayan massif encounters deep tropical moisture streaming north from the Bay of Bengal. The ensuing violent thunderstorms produce not only tornadoes but also some of the largest hail ever observed (the heaviest single hailstone ever measured on earth weighed in at 2.25 pounds on April 14, 1986 during a storm in the Gopalanj District—unfortunately, the diameter of the stone was not noted).


A synoptic chart illustrating a day a tornado formed in Bangladesh during the spring of 2003.

The deadliest tornado in Bangladesh, and thus world, history (at least in modern records) was that which occurred on April 26, 1989. At least 1,300 deaths were reported from flattened villages in a region just north of the city of Dacca. On May 13, 1995 another 700 lives were lost in the city of Tangail as the result of a violent tornado. Four other tornado events have killed 500 or more people in Bangladesh since 1964 (on April 11, 1964, April 14, 1969, April 17, 1973, and April 1, 1977). In fact, at least 6,500 people have died from tornadoes in Bangladesh in the past 50 years. This list provides more details about these events (as well as a comprehensive review of world-wide tornados that have resulted in 100 or more fatalities).

ARGENTINA

Although tornadoes are relatively rare in South America Argentina has recorded some violent twisters that may have reached the F3-4 level of intensity as was the case on January 10, 1973 when 50-70 people were killed in the town of San Justo, Santa Fe State northwest of Buenos Aires.

RUSSIA

Tornado expert Thomas Grazulis has speculated that Russia might receive the largest absolute number of tornadoes each year, following the United States, due to its vast size and “potential for small tornadoes”. Violent tornadoes, however, have been known to occur as was the case on June 9, 1984 when as many as 400 people were reported killed during an outbreak in a region 150-200 miles north of Moscow.

WESTERN EUROPE

Violent tornadoes are extremely rare anywhere in Western Europe although many weak ones occur every year. The deadliest tornado in Western Europe’s history struck three textile and paper mills near Monville, France on August 19, 1845 killing at least 70 people. Sketchy reports of waterspouts coming ashore in the Mediterranean claim fatalities of 500 in Sicily in December 1851 and 600 killed in the Grand Harbour at Valetta, Malta on September 2, 1551. There seems to be few details concerning these events and uncertainty as to the actual dates of occurrence.

SOUTH AFRICA

The only country in Africa to occasionally report a violent tornado is South Africa where powerful thunderstorms often erupt during the summer months of November through February. The deadliest tornado outbreak in the nation’s history was that of November 30-December 2, 1952 when 31 people were killed in the towns of Albertynesville and Paynesville near Johannesburg.

JAPAN

In Japan about 20 tornadoes, or tatsumaki (dragon whirls), are reported annually. These are most often associated with super cell thunderstorms that develop along the Pacific Coastline during the summer months. Weaker winter tornadoes (similar to those that affect the U.S. West Coast during winter storms) are also known to form. However, the strongest tornado in Japanese history was one of these winter ones which hit the coastal city of Mobara (20 miles southeast of Tokyo) on December 1, 1990. It was rated as a F-4 and destroyed over 1000 buildings and injured 100 people. There were no fatalities. The deadliest tornado in modern Japanese records killed 16 at an elementary school in Miyazaki city on September 26, 1881.

AUSTRALIA AND NEW ZEALAND

Australia reports about 20-25 tornadoes a year, the same number as New Zealand, and in both cases they are usually relatively weak. Occasionally they become strong enough to warrant an EF-3 rating. New Zealand’s deadliest tornado was that which struck the towns of Frankton and Hamilton in August 1948 killing three and injuring dozens. It was rated as a F-2 in intensity.

Australia’s deadliest twister was that of August 14, 1971 when three were killed at Kin Kin (a small community between Gympie and Noosa) in southern Queensland.


The Bucca, Queensland tornado of November 29,1992. The only F4 tornado so far officially reported in Australia. Photo courtesy of “Emergency Management Australia”.

SUMMARY

The Top Ten Deadliest Tornado Outbreaks on Record in the World Since 1900

1. 1,300 fatalities in Bangladesh on April 26, 1989
2. 747 fatalities in the USA on March 18, 1925
3. 700 fatalities in Bangladesh on May 13, 1996
4. 681 fatalities in Bangladesh on April 17, 1973
5. 660 fatalities in Bangladesh on April 14, 1969
6. 500 fatalities in Bangladesh on April 4, 1964
7. 500 fatalities in Bangladesh on April 1, 1977
8. 454 fatalities in USA on April 5-6, 1936
9. 400 fatalities in Russia on June 9, 1984
10. 330 fatalities in USA on March 21-22, 1932

(the April 27, 2011 event resulted in 325 fatalities and thus would probably rank as the 11th deadliest tornado outbreak in the world since 1900).

Deadliest Tornado Outbreaks on Record by Continent Since 1900

ASIA
1,300 fatalities in Bangladesh on April 26, 1989

NORTH AMERICA
747 fatalities in the USA on March 18, 1925

EUROPE
400 fatalities in Russia on June 9, 1984

SOUTH AMERICA
70 fatalities in Argentina on January 10, 1973

AUSTRALIA
3 fatalities on August 14, 1971

OCEANIA
3 fatalities in New Zealand on August 25, 1948

REFERENCE: The single best reference work about tornadoes and tornado history is Thomas P. Grazulis’s masterpiece Significant Tornadoes: 1680-1991. A supplement to this was published bringing the data up to 1995. Unfortunately, no further editions have been published to cover the past 17 years although his web site has done so but only up to 1998.

KUDOS: Mark Stroud at Moon Street Cartography for the table of F-5 tornados 1900-2006.

Christopher C. Burt
Weather Historian

- Weather Underground

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