Snowstorms
It is the car and the shovel, not the cold.
About 70% of winter storm deaths happen in automobiles. Roughly 100 more people a year die while shovelling snow, and over half of those are cardiac. The safest thing most households can do in a snowstorm is stay off the road, and stop shovelling before they are tired rather than after.
Decide now what would actually make you drive in a snowstorm. Most of the reasons people give themselves at the time do not survive being written down in advance.
