Had an opportunity (if you call it that) to ride my new Avon Cobra Chrome 250 rear in the rain yesterday. Full disclosure - it was cold, maybe 8C (46F) on clean, old pavement, urban main street, no sand, no tar snakes, no painted lines, straight line, new tires have been scrubbed in, pressure is... I forget, 40 something?
Keeping in mind I also just recently ran all day in wet conditions with Stavros on the Ontario ride and had no problems:
Last night I was coming around on a left turn and taking it easy on purpose due to the rain, 1st gear...all good, out of the turn, 2nd gear ok... slight blip in 2nd gear - and I mean GENTLE blip... rear let go for some brief fishtail-ish action! wtf?! Caught me a little by surprise as I was already moving and did not expect the rear to let go like that in a straight line with so little torque applied.
My first two thoughts - check and adjust the pressure and maybe it was the 8C temperature + wet + torque which was just too many factors for the tires to hold on?