Weather Plays Role in Election Day Outcomes

Tomorrow is Election Day. The seemingly-endless campaigning, non-stop political ads, and intense debates have finally come to an end. Now, it's time to cast your vote. Unfortunately, Mother Nature doesn't seem to want to cooperate. Rain showers are likely with a possible thunderstorm as high temperature climb to between 60 and 65 degrees Tuesday. Does weather actually play a role in voter turnout? Only recently has science been applied to illustrate that bad weather on Election Day can indeed change the course of history.

The longtime belief is that rain hurts Democrats. Generally speaking, Democrats are more likely to live in cities and tend to be less affluent than Republicans. Consequently, they are more likely to walk to the polls or depend on public transportation. So logically, rain might discourage more Democrats than Republicans from getting out to vote or from waiting outside crowded urban polling places.

A recently released study confirmed that belief. The Republicans Should Pray for Rain: Weather Turnout and Voting in U.S. Presidential Elections was published in The Journal of Politics in June of 2007. A team of political scientists cross-referenced voting data and weather reports from more than 3,000 counties for presidential elections from 1948 to 2000.

The researchers carefully adjusted for differences in normal precipitation from place to place by factoring in, for example, the greater likelihood of wet weather in Seattle and Portland, Oregon, than in dry areas such as Los Angeles. Overall, the researchers found that "rain does have a significant effect decreasing the Democratic vote share," said political scientist Brad Gomez, a co-author of the study.

"For nearly 95 percent of our observations, the effect of rain on vote share is positive, significant, and increases in magnitude as the county becomes more Republican," the study found. Specifically, "for every one-inch increase in rain above its election day normal, the Republican presidential candidate received approximately an extra 2.5 percent of the vote," the study found. "For every one-inch increase in snow above normal, the Republican candidate's vote share increases by approximately 0.6 percent."

So if it's raining or snowing on Election Day, the challenge for Democrats is to overcome the Republican advantage by better mobilizing their supporters, the researchers said. "Otherwise, Democrats may wish to pray for dry weather," they said. The single most impressive example of rain dampening enthusiasm occurred in 1972 in Tunica County, Mississippi, the researchers reported. Over four inches of rain (4.37") fell on Election Day that year, and voter turnout plunged 3.8 percent.

In the hotly contested 2000 election, better weather in Florida could have tilted it into Democrat Al Gore's column, the study concluded. That would have made irrelevant the recount that led to George W. Bush's victory in the U.S. Supreme Court that year. In 1960, the study said, Richard Nixon would have won an additional 106 electoral votes --- and the presidency --- had the weather been bad in Delaware, Illinois, Minnesota, Missouri, New Jersey, New Mexico and Pennsylvania, all closely contested states Kennedy won that year.

Although the weather was pretty bad across the country on Election Day in 1972 and 1992, the outcomes those years were so lopsided for Nixon and Bill Clinton, respectively, that less precipitation couldn't have changed things, the researchers said. So, the obvious conclusion is that the tighter the election, the more important the weather becomes, according to the study.

We'll see whether the weather influences this year's elections. There are many local races on the ballot. Make sure you take your umbrella and cast your vote.

Paul