Updated: March 20, 2012, 12:00 p.m. EDT

Preliminary tornado statistics including records set in 2011

2011 was an unusually active and deadly year for tornadoes across the U.S., with a total of 1,691 tornadoes reported across the country, more than any other year on record except for 2004, which saw 1,817 tornadoes. Several tornado records were broken in 2011, including for greatest number of tornadoes in a single month (758 in April) and the greatest daily total (200, on April 27).

May 2011

• NWS's count of 326 tornadoes occurred during the month of May 2011. There were 178 fatalities in May (158 of those in the Joplin EF-5 tornado alone).

• The record number of tornadoes during the month of May was 542 tornadoes set in May 2003.

• The average number of tornadoes for the month of May during the past decade is 298.

• May is historically the most active month for tornadoes.

• This was the deadliest May since 1933.

• The deadliest May for tornadoes in the U.S. occurred in 1896, with 502 deaths.

• On May 24, 2011, deadly tornadoes claimed 18 lives in Oklahoma (10), Kansas (2), and Arkansas (6).
  

  Before and after aerial photos of St. John's Hospital in Joplin, Mo.

  (Credit: NOAA)

• During the severe weather outbreak, two separate tornadic supercells approached Norman, Oklahoma and the National Weather Center building where NOAA National Weather Service facilities are located.

• The NWS Weather Forecast Offices, which are responsible for critical minute–by-minute warnings, continued critical life-saving operations throughout the tornado outbreak. Back-up plans could have been implemented had the staff felt an imminent threat.

• The NOAA NWS Storm Prediction Center, which has longer range national watch and forecast responsibilities, proactively passed operations to their back-up, Scott Air Force Base, in an orderly manner, after assuring watches and notifications were in place.  No SPC services were disrupted by the temporary transfer.

• Latest National Weather Service headlines:

  Everyone in the National Weather Center building other than the National Weather Service staff went to shelter.

• On Sunday, May 22, 2011, an EF-5 tornado hit the city of Joplin, Mo., leaving an estimated 157 people dead.

• The Joplin tornado is the deadliest single tornado since modern recordkeeping began in 1950 and is ranked as the 7th deadliest in U.S. history.

• 

  NOAA satellite shows storm system moments before spawning tornado in Joplin, Mo.

  (Credit: NOAA)

  The deadliest tornado on record in the U.S. was on March 18, 1925.  The “Tri-State Tornado” (MO, IL, IN) had a 291-mile path, was rated F5 based on a historical assessment, and caused 695 fatalities.

• The EF-5 Joplin tornado had winds in excess of 200 mph, was ¾ of a mile wide, and had a track lasting six miles. 

• NWS responded to the increased need for staffing by sending additional forecasters to the Springfield, Missouri Weather Forecast Office.  The larger team is now able to support the ongoing severe weather operations as well as the first responder response and recovery efforts in Joplin.  An Incident Meteorologist has been deployed to the Incident Command Post.    

• More information on the Joplin tornado is available online: http://www.crh.noaa.gov/sgf/?n=event_2011may22_summary

• Service Assessment for Joplin, Missouri, Tornado, May 22, 2011

• The NWS Springfield, Mo., Weather Forecast oOffice issued a tornado warning  at 5:17 p.m. (local time), with 17 minutes of lead time for touchdown and 19 minutes lead time before entering Joplin.  At 5:41 p.m., the local storm report stated: “NUMEROUS REPORTS OF TORNADO ON THE GROUND WEST OF JOPLIN AND POWER FLASHES.”  The damage path began at South Black Cat Road and Newton Road.

• The NWS Storm Prediction Center highlighted southwest Missouri for the potential for severe weather several days prior to Sunday's storm. SPC also issued a tornado watch more than four hours in advance of the tornado touching down.

• The Marion County long-track EF5 of 27 April 2011 claimed 78 lives.

2011 Preliminary Annual Statistics

• NWS’s preliminary estimate is that there have been 1,691 tornadoes in 2011.

• The previous yearly record number of tornadoes was set in 2004 with 1,817.

• The overall yearly average number of tornadoes for the past decade is 1,274.
  • The preliminary estimated number of tornado fatalities for 2011 is 550. NWS records indicate that there were 364 tornado fatalities before the Joplin event. There were 158 fatalities from the Joplin tornado.
• 2011 is ranked as the 4th deadliest tornado year in U.S. history.

April 2011

• April 2011 is ranked as the most active tornado month on record with 758 tornadoes (For more information, please visit NOAA's Storm Prediction Center). There were an estimated 364 fatalities.
  • The previous record for April tornaodes was set in April 1974 with 267 tornadoes.

  • The average number of tornadoes for the month of April during the past decade is 161.

  • The previous record number of tornadoes during any month was 542 tornadoes set in May 2004.

• NWS records indicate 321 people were killed during the April 25-28 tornado outbreak.

• NWS records indicate 360 people were killed by tornadoes during the entire month of April 2011.

• April 25-28 Preliminary Tornado Tracks Map (Based on NWS Storm Survey Findings)

• Service Assessment on Historic Tornadoes of April 2011