Car Dies in Wet Weather

I have a 1998 with 177,000 miles that still runs great. In wet weather and with the car in gear and stopped, it will routinely die on me. It will be running and idling smooth. It starts right back up and again runs great. I can't figure it out. The car will not die once all summer, but come winter or a wet spring day and I can count on it to die at least once in a 25 mile stop and go drive. The plugs and wires were changed very recent with no change. The car has been doing this for a couple years and doesn't get any better or worse.