Rough idle on my 2002 town and country

i have a 2002 town and country and it seems like in the summer temps of florida make the van skip, feels like a miss in the motor. we had the compression checked it was fine. the van can run for hours and all of the sudden at the next red light it starts again, about 30 sec. then idles fine then skips again, only at idle. driving down the road it runs great. what advice do you have. cb