According to AAA of Texas, you and I need at least a 1/2 full tank of gas as we get ready for this winter storm. That will help in case you become stranded, and can prevent your gas line from freezing.
Also, make sure your car battery is strong. Many auto-parts stores will check it for free.
Your tires are inflated correctly, they lose 1-2 PSI per 10 degree temperature drop.
Your windshield wipers and wiper fluid are crucial to drive in the snow. Again, many auto parts stores will install for free
If you have to drive, take your time and make sure you have an emergency kit including:
Blankets, extra coats, gloves, water, kitty litter or sand for traction, and an ice-scraper or snow brush.