I've experienced complete opposite weather on my 2 trips both at the end of April. 1st time at CN was very rainy and cloudy almost the entire time (10 days). Ended up finding out later it was a very unusual amount of rain for the time we were there. The 2nd trip to CSA was always sunny, no clouds and rained maybe 15 minutes the entire time. I'm really interested on how it will be this coming April! Although I totally prefer all sun and no rain, it didn't ruin our 1st trip either.
I have been going to CSA in mid-April for over 14 years. The weather is the same all the time. It will be in the mid to high 70s when you wake up in the morning. It will be hot at lunch. It will probably rain for a while in the late afternoon. And it will be tolerably humid all the time.