Wisconsin winters are the pits. I don't have a heated garage so I resort to using a touchless wash regularly during the freezing winter months.
I think it is just as important to keep your car spotless in the winter as in the summer months, maybe moreso. The accumulation of salt, sand and grit laying on the paint and then getting covered with snow means instant swirls as it slides off.
Granted touchless washes are harsh, but clearly not as harsh as the salt, sand and winter grime. Another advantage is that they do an underbody flush to remove the ice and salt.
I begin the winter with a couple coats of sealant (M21, this year its Ultimate Wax) and a topper of Meg's #16. I typically run through the touchless at least weekly and then run it home and do a QD and apply D156 to refresh the wax that the harsh detergents might have compromised. The nice thing about D156 (a.k.a. UQW) is that it can be applied to everything and it's really quick. I use it on glass and vinyl as well and it offers good protection. The car usually comes out of winter looking nearly as good as it started.
If you're in the same boat, and you find a good touchless wash facility, speak with the owner about a bulk purchase. I negotiated a package of 16 codes for $50, or about $3 a wash.
