As you're quite aware, even "just around town" can get pretty hazardous in the winter. Seattle, with it's mild weather, had a freeze a few years ago and EVERY road was blocked with stuck cars. Some of those people ended up sitting in their cars for 4 + hours while the roads were cleared and reopened. Others walked and just abandoned their cars in the roadway causing other problems. Even if you had a 4WD with 4 wheel chains you would have had a hard time getting around because of all the stuck vehicles.

Year round I keep a blanket & provisions but in winter I bulk up my kit just like you did. I agree on the shelter addition though
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