Weather's Impact on Voting

Newswise — An Indiana State University study has confirmed the widely held belief that weather plays a role in voter turnout, and appears to be a greater influence on Hoosier voters than those in Kentucky. Researchers in the university's department of geography, geology and anthropology reviewed voter turnout records in Indiana and Kentucky for 20 primary and general elections between 1990 and 2000. They also examined temperature and precipitation records on the dates of elections. Geography professors Jay Gatrell and Greg Bierly completed the Kentucky study in 2002, and then set to work with a team of students to examine Indiana records.

"The data suggest that Indiana is more susceptible to being influenced by weather events than neighboring Kentucky," Gatrell said.

And the Kentucky study had already found that if inclement weather kept enough people from the polls, the outcome of an election could be swayed.

"There was a statistically measurable influence of minimum temperatures on voter turnout. That was the principal variable." Bierly said. "The measurement was probably a little more significant for independent voters than it was for traditional Republican or Democratic declared voters."

Throw in a little rain, and voter turnout declined further, Gatrell noted. "The interaction between the two in our model suggests that is even more dynamic," he said.

"We here a lot about weather and rain and reduced turnout but most of it is anecdotal. There's really no previous systematic study of voter turnout and inclement weather's influence on it." The Indiana State study found 23 percent of the difference (observed variance) in voter turnout for general elections in Kentucky was attributable to the study's weather model. In Indiana, that number rose to 54 percent. In primary elections, weather was blamed for 32 percent of the difference in voter turnout in Indiana compared with 25 percent in Kentucky. Both states hold primaries in May.

Weather was a greater deterrent to independent voters than registered Republicans or Democrats in Kentucky. Indiana does not keep records of voter turnout by party affiliation. Weather was more likely to impact state elections in both states rather than national elections.

Bierly and Gatrell got the idea for the study one cold, rainy evening during the 2000 Florida recount.

"The margin of voter difference for the presidential candidates looked like it was going to be within the margin of error for the voting machinery itself, so we began to ask ourselves if some external factor could actually influence an election," Bierly said.

"If you had a situation where the voting margin was incredibly close, as it was in the Florida recount, then weather could exert an influence," he said. Following the recount, President Bush carried Florida by barely 500 votes out of more than 6 million cast.

Kentucky was chosen for the initial study because it is considered a bell weather state in national politics, That Indiana voters appear to be more likely to stay home when the weather turns bad may be due to the traditionally Republican state being less competitive politically, Gatrell said.

"The competitiveness of races, the overall competitiveness of party systems and moneys that are dumped in by national campaigns during Presidential years all influence the political culture of a state," he said. "The political culture of Indiana and Kentucky are decidedly different and in both cases weather influences, but the exact influence is spatially distinct. Indiana appears to be more susceptible to diminished turnout as a result of inclement weather."

The study, completed last spring, was published in September in the Journal of the Indiana Academy of Social Sciences under the title "Blame it on the rain! Exploring the distinct political cultures of Kentucky and Indiana using turnout data and observed weather conditons." Gatrell and Bierly plan to expand their study of weather and voting to the entire Great Lakes region.

ISU Public Affairs: http://isunews.indstate.edu