yeah a more narrow tire does help in snow but thats just about it. i would assume it does in rain aswell because with a wider tire you would most likely be more at risk of hydroplanning.
any good mechanic shop should be able to measure your offset and everything to help you find a good set of tires and wheels that will fit. call around and see if you can find one that will even do it for free if you purchase the tires from them.
hn155: Rockford punch pro speakers, t400.4 deh 80prs, full audio build to come. working towards 175hp n/a, simple but fun.