It depends. There were several major tornado outbreaks in 2011. The most significant lasted just over 3 days, from April 25 into the morning of April 28.
The last confirmed tornado was in Texas on September 17, 2011. It was rated EF0
The last tornado to hit Akron was an EF0 on May 25, 2011.
The last tornado to touch down in 2011 was an EF0 southwest of Atlanta, Georgia on December 22 at 5:18 pm. It was the last of 13 tornadoes that occurred on that day.
As of February 8, 2012 the last tornado to hit Georgia was on December 22, 2011.
As of May 18, 2012 the last tornado in New Mexico was on August 3, 2011.
The Joplin, Missouri tornado of May 22, 2011 lasted 38 minutes.
The last confirmed EF0 tornado occurred at about 4:20 PM in Craven County, North Carolina on April 28, 2011.
The last tornado to hit Pennsylvania was an EF0 in York on April 16, 2011. It damaged several businesses and snapped a few trees.
Today, May 18, 2011
The deadliest tornado in this tornado season (2011) hit Joplin, Missouri on May 22, killing 158 people. The last deadly tornado this year hit Springfield, Massachusetts on June 1, killing 3.
The most recent tornado in Texas was an EF1 that touched down on February 1, 2011.
In 2011 there were 552 tornado fatalities in the United States, tying it as the second deadliest tornado year in U.S. history.