By the numbers: How record cold could impact Iowa caucuses

Freezing temperatures and strong winds foreshadow possibly life-threatening conditions for Monday night, when caucuses begin at 7pm, per the National Weather Service Des Moines office.

Why it matters: Turnout is always the x-factor in elections, but that's particularly true at the Iowa caucuses. In some rural precincts, as few as 10 people can make a big difference.

The bottom line: It's unknown how the extreme weather could affect Donald Trump's lead because many of his supporters are in rural areas, where it'll be harder to travel to caucus sites.

• And given expectations, lots of people could stay home — assuming Trump will win. But he also has some of the most enthusiastic supporters, which could play in his favor.