• April 19: Skynet is brought online after an unknown entity creates it.^[1]
• April 21: Judgment Day. Kyle Reese and Derek Reese witness the launch of U.S. missiles while playing ball in their yard.^[1][2]

References

1. ↑ ^{1.0 1.1} Terminator: The Sarah Connor Chronicles, pilot episode
2. ↑ Terminator: The Sarah Connor Chronicles, "What He Beheld"