For all of the elegance of representative democracy, the theoretical consideration of candidates and balancing of their issues and your priorities, the outcomes of elections depend solely on who actually comes out to vote. That's historically been disadvantageous for Democrats, since the party's voters are more likely to fall into demographic groups that vote less frequently: people of color, poorer people, younger people.
It could also play a significant role in the upcoming caucuses in Iowa. Donald Trump leads in recent polls in the state, but his support is more heavily composed of people who are less likely to vote -- meaning that if there's any sort of obstacle between his voters and the place where they need to go to caucus, it's a problem.
Bernie Sanders has a similar problem. We've noted repeatedly that Sanders similarly depends on less-frequent voters, and that his support also depends on young people in three counties -- Black Hawk, Johnson and Story -- where there are big universities that are showing him a lot of support. (The largest cities in those counties are Waterloo, Iowa City and Ames, we'll note for reasons that are about to become obvious.)
With the East Coast blizzard looming last week, we overlaid another worry onto this picture: weather. Studies have shown that bad weather can have a negative impact on turnout, and Iowa in February is not immune to bad weather.
We are now one week from the day of the caucuses -- meaning that we now have weather forecasts at our disposal. Which means, too, that we can now see how weather may or may not affect turnout in areas that are important to the 2016 candidates.
Here are the latest weather forecasts for Election Day, at most three hours old. (This data is via OpenWeatherMap.) We've included maps of where past candidates did particularly well or poorly, to give you a sense of which areas will be most important to the candidates. And, underneath, that data broken out for easy perusal -- including the evening temperature, to give a sense of what things will look like as the clock runs down.
As of writing on Monday afternoon, there's some snow expected in the northwestern corner of the state, an area that has been a focus of Ted Cruz's and which backed Rick Santorum by a wide margin in 2012. Does this mean Cruz may lose a close election? No, probably not. But it means he may need to start thinking about investing in some shovels.