Sometimes when it rains and my car would sit in the driveway, then i would go outside after the rain and the car would start fine then when i was driving it after the rain it would start to miss and hesitate. When i came to stops the RPMs would drop and the car wants to die. One other thing, on the way up to school on the freeway i was going about a steady 100mph in sixth gear with cruise on and it starts to miss. The problem will continue in any gear only when it reaches 4500rpm and beyond. It only misses with about two thirds or more throttle. These problems only happen only once in a while.

 

Do a search on the opti-spark. That is most likely the cause of all of your missing problems. when it rains, its obviously really humid which may be causing the opti do get damp due to condensation. if the temp is right. That may be why it does it some of the time. Good luck on your finds.