Always gotta have some matches in yer pocket, always.
I've been carrying in my pocket my old faithful ZIPPO with the opening tightly sealed with a rubber band I cut from a bicycle tube, for many years. The rubber band keeps it dry.
I've tested it three different times by leaving it in a jar of water for two hours. When the band is removed the lighter fires up with the first strike and has a clean flame. Works for me in all kinds of weather.
L.W.