I no longer do rides in the rain for fun. The last time was during one 50-mile day stretch of a 183 mile 3-day ride with an organized group which had support crews of baggage trucks, food distribution, mechanics, ambulance-mounted paramedics, and vehicles to pick up exhausted riders. The whole day was a massive downpour of rain in cold temps (it is Maine after all). After 40 miles, hypothermia set in and I ended up going the rest of the day's ride in an ambulance to where we would stop for the night.

Never again unless I just happened to get caught in a sudden rainstorm in which I will successfully complete my ride or finish it with no ill effects.