My worst turbulence was on a GA 40 minutes domestic flight PLM-CGK back in 1988. The 717 (or DC9 ?) flew through a thunderstorm and the plane dropped tens of meters at once. I heard screaming on board but the turbulence lasted not more than a few seconds.

In 2014, flight KL597 AMS-CPT (a 777) was very bumpy straight after takeoff from Schiphol due to windy weather. Winds were decreasing, I expected a delay of hours, but we left on time. Many flights were canceled or delayed.