advice on wheel/tire combo

i have an '03 sentra 2.5 le, it has the standard alloys and fs potenza tires that came stock, i'm considering replacing it with a larger wheel. can i get wider tires? and will it sacrifice safety in wet conditions?

total n00b

215 is the largest I would go, even on 225 the tire will rub on the fender on bumps if you don't roll the fenders. 215/45/17 is the stock size on the spec, that's the size I would go with if you plan on going with 17's.