Rode to the beach yesterday.  First ride of 2016.  It was cold and overcast.  Started out at 57 degrees and never got much warmer.  It was a good day for layers of clothing.  Got a cramp in my left hamstring with about a half mile to go.  Man that hurt.  Probably not enough fluids.  You're no as thirsty when it's cold, but you have to continue to drink or your body tells you to by cramping up.