The current weather forecast for November 2, 2010 looks ugly for the middle Atlantic East Coast with easterly winds and rain chances set up between a Canadian high pressure cell and a developing SE US low. Temperatures there are expected to be in the 40s and 50s. The Pacific Northwest may also see considerable wet weather.
There are some old axioms that certain political parties in the USA should pray for rain or sunshine, but in early November, you never know what you will get in terms of weather. A study a few years back by Florida State University professor Brad Gomez comprehensively analyzed the relationship between Presidential voter turnout and weather using over 20,000 individual weather stations from 1948-2000. In their paper, Gomez et al. found empirical evidence that rain (snow) reduces voter participation by about 1% (0.5%) per inch, and may have affected the electoral outcome of the 1960 and 2000 presidential elections.
While the upcoming November 2 midterm elections have a significantly lower voter participation than Presidential years, it is likely that weather is more important to voter turnout and election outcome. This type of study is a great way to combine social and physical sciences to model effects of weather and climate on political issues — rather than vice versa.
Abstract of paper:
The relationship between bad weather and lower levels of voter turnout is widely espoused by media, political practitioners, and, perhaps, even political scientists. Yet, there is virtually no solid empirical evidence linking weather to voter participation. This paper provides an extensive test of the claim.We examine the effect of weather on voter turnout in 14 U.S. presidential elections. Using GIS interpolations, we employ meteorological data drawn from over 22,000 U.S. weather stations to provide election day estimates of rain and snow for each U.S. county. We find that, when compared to normal conditions, rain significantly reduces voter participation by a rate of just less than 1% per inch, while an inch of snowfall decreases turnout by almost .5%. Poor weather is also shown to benefit the Republican party’s vote share. Indeed, the weather may have contributed to two Electoral College outcomes, the 1960 and 2000 presidential elections.
The results of the zero precipitation scenarios reveal only two instances in which a perfectly dry election day would have changed an Electoral College outcome. Dry elections would have led Bill Clinton to win North Carolina in 1992 and Al Gore to win Florida in 2000. This latter change in the allocation of Florida’s electors would have swung the incredibly close 2000 election in Gore’s favor. Of course, the converse is that a rainier day would have increased George W. Bush’s margin and may have reduced the importance of issues with the butterfly ballot, overvotes, etc. Scholars have identified a number of other factors that may have affected the Florida outcome (see Brady et al. 2001; Imai and King 2004; Mebane 2004)—it was, after all, a very close election with only 537 votes separating Bush and Gore—but to our knowledge we are the first to find that something as simple as rainy weather in some of the Florida counties may have played a critical role in determining the outcome of a presidential election.
The partisan bias associated with weather depressed voter turnout can have meaningful repercussions for election outcomes. Our simulation results for the 1960 and 2000 presidential elections are key examples. The closeness of the 1960 race (a scant 118,000 popular votes separated Kennedy and Nixon) made several states pivotal in the Electoral College, including Illinois, where allegations of vote fraud undertaken by Chicago Mayor Richard J. Daley followed
Kennedy’s 9,000 vote victory. We cannot say whether Kennedy’s victory benefited from such actions, but we can claim that Kennedy benefited from relatively good weather. In responding to the Florida debacle in the 2000 presidential election, Democrats complained incessantly about a litany of factors that stood as obstacles to a Gore victory: “butterfly ballots,” “hanging chads,” the Florida Secretary of State, the newly elected president’s brother (the Governor of Florida), and, of course, the Republican-appointed Justices on the United States Supreme Court. Yet, our results show that the weather may have hurt their cause just as much. In close elections, the weather becomes one of many factors that can be determinative.
It is clear from our results that Republicans benefit from precipitation on election day. To offset these Republican gains,
Democrats must take action to counteract the increased cost of voting among their supporters. Otherwise, Democrats may wish to “pray for dry weather.”