1. In 1952, the deadliest tornado to ever hit the state of Oklahoma occurred on June 27th. The storm, known as the "Woodward Tornado," killed 116 people and injured 676 others.

2. On June 27, 1911, the city of Tulsa celebrated its first-ever Flag Day. The holiday was initiated by a local women's club, and has been observed in the city ever since.

3. In 1981, the Oklahoma City Thunder (then the Seattle SuperSonics) drafted future Hall of Fame player Nate McMillan on June 27th. McMillan played for the team for 12 seasons and later served as the head coach.

4. On June 27, 1906, the Oklahoma State Penitentiary in McAlester opened its doors for the first time. The prison, which still operates today, has been the site of numerous riots and protests over the years.

5. June 27th is also known as National PTSD Awareness Day, a day dedicated to raising awareness about post-traumatic stress disorder and its effects on veterans and others who have experienced trauma. Oklahoma has a high population of veterans, and many organizations in the state work to support those struggling with PTSD.