1. The Wyoming 14: On December 13, 1995, 14 snowmobilers were killed in an avalanche in the Gros Ventre Mountains near Jackson Hole, Wyoming. The tragedy received national attention and led to increased awareness and safety measures in avalanche-prone areas.

2. Wyoming Statehood Day: December 13, 1890, marked the day that Wyoming became the 44th state in the United States. The state is known for its rugged landscape, abundant natural resources, and strong sense of independence.

3. First Women Jury: December 13, 1870, marked the first time in U.S. history that women served on a jury. The trial was held in Laramie, Wyoming, and the women were allowed to serve on the jury by a provision in Wyoming's state constitution that granted suffrage and equal rights to women.

4. Snow in Yellowstone: On December 13, 2009, Yellowstone National Park experienced a record-breaking snowstorm that dropped over 30 inches of snow in a single day. The park closed all roads for several days, making it difficult for visitors to enter or exit.

5. Battle of Little Bighorn: Although it did not occur on December 13 specifically, the Battle of Little Bighorn took place over June 25-26, 1876, in present-day Montana, but is still considered a significant event in Wyoming history. The battle was one of the most famous clashes between Native Americans and the U.S. government, and resulted in a devastating loss for the U.S. Army.