Whatever you do, be cautious about washing your car in a cold climate with any hot water in the mix. I have been researching paint issues over the past year and have come across information from paint manufaturers that this causes "thermal shock' to clearcoat. The weird thing is, it supposedly dosen't visually happen right away, but rather the many tiny cracks that become visible do so after about 8 months to a year. I have wittnessed these cracks on some vehicles, one a 2000 Isuzu Rodeo SUV (black) that I detailed for the first time in 2002. I brought it to the attention of the owner before I worked on it, to save myself liability issues. I thought perhaps it was cause by a bad rotary buffing job that cause it to check/crack, but research on it led me to a site (wish I had kept the link) that was a BASF or such paint site that spoke of this hot water concern. There are perhaps other causes for this same paint issue, but I can assure you all that the hot water/cold car concern is valid according to the people that supply the paints to the manufacturers.
Not saying anyone here would do this, but given the laws of physics, it makes sense not to put anything hot on cold sheet metal. Warm may be a different story. Cheers.