Your kit should include a cell phone charger to stay connected. Blankets, clothing, work gloves, and boots should be in your vehicle for each passenger and yourself. Food and water are critical for survival if you are stranded.
A first aid kit is helpful if someone has an injury. You should also have a tow strap, jumper cables and rags handy if you want to try to get your car back on the road yourself. A shovel, cat litter for traction, an ice scraper, and duct tape may be of great help in snowy situations. Gather the items for your kit and store them as close to you as possible while you travel!