Pick out a good one or just learn about history.
https://en.wikipedia.org/wiki/April_27
2011 – The 2011 Super Outbreak devastates parts of the Southeastern United States, especially the states of Alabama, Mississippi, Georgia, and Tennessee. 205 tornadoes touched down on April 27 alone, killing more than 300 and injuring hundreds more.
https://en.wikipedia.org/wiki/2011_Super_Outbreak
April 27's 317 fatalities were the most tornado-related fatalities in the United States in a single day since the "Tri-State" outbreak on March 18, 1925 (when at least 747 people were killed)
That Great Tri State tornado in 1925 was just 1 incredible tornado and hit this area in southwest IN.
https://www.britannica.com/event/Tri-State-Tornado-of-1925
2005 – Airbus A380 aircraft had its maiden test flight.
This one has personal significance for me. I was working for Lockheed Aircraft Co. on the l-1011 Tri-star, and up till them our only competition for Jumbo jets was the Boeing 747 and the Douglas DC-10.
With the introduction of the Airbus (which was subsidized by Great Britain and France), the competition for commercial aircraft business was too intense, and Lockheed decided to concentrate on their very successful military aircraft business. I then began working on the Stealth fighter.