If it's going to be bad out I can always take my little Olympus 850SW (now Stylus Tough brand). Yeah, it's not going to be like a DSLR for quality but it can take drops, freezes and immersion...perfect for winter days with the dogs.
I don't have any WR lenses, but that 18-135WR is
REALLY tempting. Maybe if I have a second birthday this year.
I have been outside in very cold weather with the K-10. I let it warm to room temperature before placing back in the camera bag. The sensor recorded temperature for each picture, which was pretty interesting. Single digits F.