May as well ride in the rain...When ever I take my bike somewhere by car, it inevitably rains there and back- so she ends up getting soaked. I just re-lube the chain. I think constant rain is hard on the cables, though.
If rain is cold, I wear a rain jacket with pitzips and venting in the back, a helmet cover (I _love_ that!!!) toe covers, and either these wind/rain resistant tights from Performance or, I have a new pair of actual rain pants, but it, of course, hasn't rained since I got them...I also carry dry socks and gloves. I also have a pair of waterproof, warm gloves, but I usually don't wear them.
If the rain is warm, I just wear my normal clothes, and sandals so I don't have to worry about my shoes getting ruined (and trying to dry out wet feet!!).
Carry some ziplocks all the time so you can protect your cell phone and camera if it rains unexpectedly.
Be careful of wet leaves- very slippery. People say you flat more in the rain, so make sure you're prepared for that. It's nice to have a red LED tail light so traffic can see you. And maybe a reflective vest or jacket.
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson