My Mustang will be six years old in March. It has never seen rain (...well...once for 20 minutes when I got caught out...). But it doesn't get stored in winter. I put 10 miles or so per month on it to warm up the fluids and make the tires round again. It's easy: wait for rain to wash the salt off the roads, and for them to dry out after that. Mild winter weather like that is customary.
This winter, the car hasn't been out since early November and, based on the weather forecast, it won't make it until mid-February. Three months and counting. This has been the worst winter in Chicagoland in the 24 years I've lived here. It has combined the worst features of Cleveland (lake effect snow and grey skies day after day) and Minneapolis (biting cold for four months).