Pack an emergency get home bag that caters to the needs of winter. This pack should include hand warmers, thermal natural fiber blankets as well as the mylar emergency kind that pack so well. With extra blankets, you can use the mylar blanket as a signal for help.
This is the time to raid the pantry for MREs, meals ready-to-eat. In the package, you will find more than food. There you will have warmers for heating the food that could keep you alive if you slide into a snow bank and have to spend the night waiting for rescue.
You can use some of the insulating techniques you would use at home if you are trapped in or near your car. Trash bags are easy to pack in your car. If you have to sleep in your car, put down a plastic barrier. Better one down than two over! You can cut a slit in the bottom and put the bag over your head to add a wet weather barrier to your clothes if you have to walk out.
And, just because I believe it needs saying, pack black bags to contrast against the white snow.
Pack a roll of duct tape. You can build a small city with a roll of duct tape and a roll of trash bags! Cut squares of duct tape and join barriers at the corners and the occasional point in between. If you use a whole roll of tape to cover a single seat, you will eventually have to scrape off the adhesive.
At home, you will have a bit more time and security to prepare for a snowed in survival prep. Practice what you have been preaching to the family.
Duct tape and plastic over interior of windows, roll plastic bags into a tube and tape them to the bottom of doors against drafts, create curtains to keep heat in central rooms.
Separate foods that require heavy consumption of fuel to prepare from your more 'instant' prep foods. For common sense, cook the hearty stews or roasts first. Should power go off, then fall back on the easily reheated or easily warmed foods. For these foods, you will need an alternate source of heat such as a small propane or butane burner or a sterno stove.
In the Warming up your Wardrobe post, you can get some suggestions for dressing warmer. Inside or outside, you must keep heat from escaping your body. Wear socks in home and keep shoes or boots nearby if you must leave suddenly. Stack all your blankets for sleep in the corners of your winter retreat room. It's best to sleep in a group in a single room that you can keep warm than to try to spread out. If the power goes out in the night the cold children will be wandering the cold house looking to you to to find the warm cuddly blankets in the middle of the night.
Get ready, it's going to be a long cold winter. Grab your gear and get ready.