sentences:  Tornado outbreak sequence of April 20–26, 2007
  
  The April 20–26, 2007 tornado outbreak sequence was an extended period of tornado activity that occurred in late April 2007.The outbreak sequence is best known for producing a deadly pair of tornadoes that struck the border cities of Piedras Negras, Coahuila, and Eagle Pass, Texas, along the United States-Mexican border on April 24, 2007.