Snow

“Snowmageddon” is the Twitter nickname for the snowstorm hitting the northeastern US and Canada at present - apparently New York is expecting the worst snows since 1888. Most firsthand reports suggest people shovelling a bit more than usual, quoting Game Of Thrones and carrying on.

Ice and snow can affect footing as well as visibility, and the cold saps endurance.

Also, snow goons. 

And of course the 1888 thing has me imagining something reappearing out of the storm from over a century in the past.