We encourage everyone keep a mini survival kit in your vehicle all year long, but Winter is definitely here and you need to be prepared.
We suggest you consider the Survive Outdoors Longer Heavy Duty Emergency Blanket or one of their other blankets or bivies, based on your needs. They are available with OD or Orange face fabrics and are backed by reflective foil material (90% heat reflective) which will help keep you warm.
Wind and rainproof, it can be used as a ground cloth, blanket, sleeping bag, or shelter. The Heave Duty Emergency Blanket is 5′ x 8′ and weighs 7.9 oz. This one also slightly thicker (2.5 mil) than other emergency blankets which are 1 mil thick*.
*A mil is a measurement that equals one-thousandth of an inch, or 0.001 inch. One mil also equals 0.0254 mm (millimeter).
I left one of their 2 person original heatsheets up as a plow point shelter for over 2 months during winter with a light debris( pine needles) covering, at the end it had streched a bit at the tie offs and sagged a little from wet frozen pine needles, but no holes and underside was completely dry- a quick rehang made and debris change and it was completely fine. If this one has the same ability to stretch rather than tear ,it can’t be anything but good .
I have one of the even thicker reinforced 5×7 “sport utility” versions of these in each of my vehicle go bags, in addition to the smaller and more compact 2-person emergency blanket.
At 3/4 a pound it is pretty heavy, but the utility it offers is worth it, it has grommet holes for easier and faster tie down, especially if it is windy, and it has fiber reinforcements throughout, like a tarp.
My partner and I had the SOL emergency bivvy in our bags as we got stuck in a storm in the mountains a few years ago. The temperature dropped significantly when the rains came in and those bivvies were integral to keeping us out of danger that night. I keep SOL blankets or bivvies in all vehicles and packs.