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Through Tornado, Bangladesh and East India

There were 1,715 tornadoes confirmed in the United States in 2011, which was the third most in a single year on record, with only 2024 and 2004 having more confirmed tornadoes. 2011 was a catastrophic and extremely deadly year for tornadoes; worldwide, at least 570 people perished due to tornadoes: 12 in Bangladesh, three each in Russia and Japan, two in South Africa, one each in New Zealand, the Philippines, Greece and Canada, and 547 in the United States (compared to 564 deaths in the prior ten years combined). Due mostly to several extremely large tornado outbreaks in the middle and end of April and in late May, the year finished well above average in almost every category, with six EF5 tornadoes and nearly enough total tornado reports to eclipse the mark of 1,817 tornadoes recorded in 2004, the current record year for total number of tornadoes.

The 547 confirmed fatalities marks the second-most tornadic deaths in a single year in U.S. history, behind only 1925 in terms of fatalities attributed to tornadic activity. Most of the damage and over two-thirds of the total fatalities in 2011 were caused by a late-April Super Outbreak and an EF5 tornado that struck Joplin, Missouri, in late May, becoming the costliest tornado on record.

Synopsis

An ongoing outbreak at the end of 2010 continued into the first three hours of 2011. During that period seven tornadoes developed in Mississippi. However, during the remainder of the month, tornadic activity was suppressed by a cold air mass, with nine additional tornadoes – all weak – taking place.

This inactivity continued through much of February before a pattern shift. Two consecutive outbreaks took place on February 24 and 27 – 28, producing a combined 55 tornadoes. Overall, 63 tornadoes were confirmed in the month, making it the fourth most active February on record. Activity in March was split between the start and end of the month - with a total of 75 tornadoes recorded, it ran slightly above average for the month.

In early April, a prolific severe weather event produced 46 tornadoes and more than 1,200 reports of wind damage, setting the tone for the month.

A nearly continuous series of major tornado outbreaks followed thereafter in the remainder of April, including two extreme multi-day tornado outbreaks that were among the largest in U.S. history (one of them the deadliest and the costliest; and the other involving a widespread tornado outbreak in North Carolina, the worst since the March 28, 1984 outbreak) and two major tornado outbreaks in a time period from April 8 - 11 and April 19 - 24, resulting in an incredibly active month. April 2011 was the most active month for tornadoes on record, with an extremely large margin of 773 tornadoes in total.

However, in an abrupt reversal, the activity did not continue into May (normally the most active month for tornadoes), and the first half was remarkably quiet, becoming one of the least active Mays on record by the middle of the month. The lack of activity continued for three weeks until a tornado outbreak sequence began on May 21, and a deadly EF5 tornado hit Joplin, Missouri the following day in the event.

Additional strong to violent tornadoes occurred on May 24 in Oklahoma, including another EF5 in the city of El Reno. The outbreak sequence continued for the next several days, with 241 confirmed tornadoes, bringing the month of May to near average. Despite its near average count of tornadoes, it was catastrophic when it came to fatalities - 158 of the deaths came from the Joplin tornado.

The first day of June brought a rare outbreak into New England. Several tornadoes occurred, some of which were destructive. However, another reversal took place afterward and much of June was fairly quiet, with the exception of an active period in the third week of the month which included a moderate tornado outbreak.

July was also relatively quiet for the most part with below normal activity, occurring mostly within the northern Plains. August was more quiet with below normal activity and only 59 confirmed tornadoes. September and October were also below average. November was somewhat more active, primarily due to two moderate outbreaks in the first half of the month. December saw a return to inactivity for most of the month, but there was a small outbreak of 13 tornadoes on December 22, making it the final tornado outbreak of the year and ending what was the worst year for tornadoes since 2008.

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