Question: On what date did the tornado occur that destroyed Plaza Towers Elementary School?

<P0-S0> On the afternoon of May 20, 2013, an intense and destructive EF5 tornado struck Moore, Oklahoma, and adjacent areas, with peak winds estimated at 210 mph , killing 24 people (plus one indirect fatality) and injuring 377 others. <P0-S1>  The tornado was part of a larger weather system that had produced several other tornadoes across the Great Plains over the previous two days, including five that struck portions of Central Oklahoma the day prior on May 19. <SEP> <P1-S0> Charleston Community Unit School District 1 is a unified school district based in Charleston, the county seat of Coles County, Illinois; it was created through the consolidation of the charter school district it was formed from and over sixty-seven other school districts in the area. <P1-S1>  Charleston Community Unit School District 1 is a conglomerate of six schools, with all but one located in Charleston itself: four elementary schools, one middle school, and one high school form the makeup of the district. <P1-S2>  Education begins at a prekindergarten level, and those living in the Charleston area attend Mark Twain Elementary School, which prepares early youth for schooling by taking them through prekindergarten and kindergarten under the supervision of principal Terry Diss. <P1-S3>  Students who live in the far east reaches of Coles County may attend Ashmore Elementary School, which is based in a northeasterly village by the same name; Ashmore's distance from the other schools permits it to educate a larger range of students for the sake of efficiency. <P1-S4>  The school educates students from kindergarten through grade four, and also runs a prekindergarten program. <P1-S5>  Ashmore is also governed by Terry Diss. <P1-S6>  Students who graduate from Mark Twain move onwards to Carl Sandburg Elementary School, which educates those in grades one, two, and three under principal Chad Burgett. <P1-S7>  At Jefferson Elementary School in Charleston, the student bodies from both Carl Sandburg Elementary School and Ashmore Elementary School are consolidated. <P1-S8>  Students from grades four through six are taught in the facility under the supervision of principal Deborah Poffinbarger. <P1-S9>  District students graduating from Jefferson are moved to Charleston Middle School, where they are taught as seventh and eighth graders; the school principal here is Sandy Wilson. <P1-S10>  The last branch of education that Charleston's school district can provide is the education of adolescents in the grades nine through twelve at Charleston High School, which is run by principal Trevor Doughty. <P1-S11>  The superintendent of the schools in the district as of the 2007-08 school year was Dr. William Hill, although is considered as an interim;lastly, the mascots of the district and its middle and high schools are the Trojans, while the mascot of Jefferson Elementary School is the bulldog. <SEP> <P2-S0> Plaza Towers Elementary School is a public elementary school in Moore, Oklahoma, in the Oklahoma City metropolitan area. <P2-S1>  It is a part of Moore Public Schools. <P2-S2>  Plaza Towers is located in southwest Moore within a neighborhood of the same name. <P2-S3>  The school's mascot is the panther, named "Paws". <P2-S4>  The school's current building opened in 2014 after the previous facility was destroyed by the 2013 Moore tornado; seven students at the school died as a result of the tornado's impact. <SEP> <P3-S0> The 1968 Tracy tornado. <P3-S1>  was an F5 tornado that struck Tracy, Minnesota on June 13, 1968 at around 7 o'clock. <P3-S2>  The tornado killed nine people and injured 125 others. <P3-S3>  The wind speeds of the tornado reached over 300 mph as it tracked 9 mi through Murray, Lyon and Redwood counties in southwestern Minnesota. <P3-S4>  It is one of only two official F5 tornadoes that have occurred in Minnesota, although several other tornadoes that occurred before 1950 are estimated to have been F5 strength. <P3-S5>  The tornado destroyed 111 homes, caused major damage to 76, and caused minor damage to 114. <P3-S6>  Five businesses were destroyed and 15 others were damaged. <P3-S7>  Some homes in town only had their foundations left behind. <P3-S8>  A few farms outside of town were swept completely away, and extensive ground scouring occurred. <P3-S9>  An elementary school and 106 automobiles were destroyed, and a heavy boxcar was thrown more than a block by the storm. <P3-S10>  Two other boxcars were thrown 300 yards, and a steel I-beam was carried for two miles on a piece of roof. <P3-S11>  Hard rains and hail were also reported. <P3-S12>  A total of five tornadoes hit Minnesota on June 13, 1968, most ranking as an F0.