I buy rain jackets from Academy Sports, their store brand, that fold up in to the pocket so they fit easily in to my park bag. I have the for my whole family, even my husband that is 6'4". I always buy them a size larger than we need to fit around bags, and over most of our clothing. I don't trust ponchos, I've seen too many people have them fly over their heads during a bad storm (which happened Presidents day weekend when my DD10 and I were in MK, we had our jackets on and only our legs and the very bottom of my skirt and leggings got wet, which both dried by the time I was done eating lunch). Once the rain is done I just fold them up and back in my bag they go, mine has been on 15 trips in 3 years since I bought it and still holding up superbly, it was $20 and paid for itself a long time ago.