When snow is in the forecast around here, the roads get treated. That is good for traction and bad for your car. Salt and brine cling to the lower half of the vehicle, and they get tracked inside on your shoes.
What salt does
Salt speeds up corrosion on exposed metal, and it dulls wheels and trim. Inside the car, it leaves white lines on carpets and floor mats that get harder to remove the longer they sit.
Before winter
The best time to deal with salt is before it arrives. A hand wash, clay and a coat of wax or sealant gives the paint a layer of protection and makes it easier to rinse clean. A wheel ceramic sealant does the same job for your wheels.
During winter
Wash the car when temperatures allow, especially after a storm has been cleared. Focus on the lower panels, the wheels and the door jambs. An Express Clean between storms is a simple way to keep up.
After winter
When the roads are clear for the season, book a deeper clean. Seat and carpet shampoo removes salt stains from the cabin, and an exterior detail takes off what built up on the paint.