My worst experience was on October 3, 1998. A Halloweekends Saturday. The chance of rain was 90% all day (it rained at least 90% of the day), the temperatures were in the low to mid 50's, and it was very windy. Unfortunately, the place was packed. It was then that I learned that weather conditions, no matter how inclement, is not a deterrent to the people that came to CP that day.
Major rides such as the Magnum, Mean Streak (big loss LOL), and Gemini would never open that day. And Raptor, Mantis, and Power Tower would operate on a on-again off-again basis due to the rain. And of course lines for these rides were very long because of all the other rides that were closed. Oddly enough, the only ride unaffected by weather conditions, Disaster Transport, never opened that day either.
I was only able to ride the Mantis, Mine Ride, Blue Streak, and the Raptor. Nothing like riding the Raptor in the front seat and have rain pelt you in the face. The only positive thing about this trip is the free ticket I received after buying my first ever season pass earlier that day.