Keeping wine in cold temperatures

My wife and I won a raffle from the daycare my sister takes her kids to and our prize was 15 assorted bottles of wine. My sister lives in a city 8 hours away from me, and I happen to be there for work this week. I met up with them earlier and now have the wine in my hotel room. I still have one more day of training tomorrow and would prefer not to come back to the hotel.

Will my box of wine be ok kept in a truck (back seat) during the day tomorrow? It will be left there for about 9 hours and the temperature is supposed to be -9c going up to -3c over g of the day. I plan on getting the cab of the truck warm and covering the box with a couple sweaters to help insulate it.