Severe storms in the US could impact voter turnout in key states

Weather can affect the outcome of an election, especially in a country like the United States where voting is optional, many races are close, and the weather itself can be extreme. Historical data shows that good weather favored John F. Kennedy's victory in 1960, while rain helped secure George W. Bush's victory in Florida in 2000.

This year, a massive storm stretching from Texas to Canada threatens to impact voter turnout as Donald Trump and Kamala Harris face off in one of the closest races in American history.

Meteorologists are predicting severe thunderstorms and rain over the next 48 hours. A cold front is expected to sweep across the central portion of the country, bringing the threat of severe weather conditions from the Great Lakes and upper Midwest down to the lower Mississippi Valley, including portions of the Texas and Louisiana coasts.

Path of the storm

The worst of the storm is expected to hit safe Republican states to the south, while key swing states Wisconsin and Michigan could also see heavy rain. Up to two inches of rain could dampen turnout in these battlegrounds, with northern Michigan and southern Wisconsin particularly affected.

Rain and snow have consistently reduced voter turnout in past elections, often favoring one party over the other. A 2023 study in Denmark found that voter turnout fell by one percent for every 0.3 inches of rain. Similarly, a 2007 US study found that rain reduces voter turnout by about one percent per inch.

These trends suggest the storm could lead to a significant drop in voter turnout in Wisconsin, Michigan and other areas with heavy rainfall.

Will Republicans benefit?

In conversation with the Australian Broadcasting CorporationUniversity of Sydney Professor Benjamin Reilly claims the US presidential race is “too close to call” with opinion polls reflecting exceptionally close competition.

Professor Rosalind Dixon from the University of NSW agrees, stressing that survey data suggests close results are possible in critical swing states, many within the margin of error. Both professors warn that bad weather could reduce voter turnout, especially among less politically engaged voters who might not go to the polls because of rain or snow.

In previous elections republican have benefited from bad weather, which often turns off voters who are less selective and more Democratic-leaning. A study by Brad Gomez found that every 0.6 inch increase in rainfall led to a 2 percent increase in the Republican candidate's vote share.

While Professor Reilly notes that the storm could hurt voter turnout in heavily Republican areas in the South, he points out that Republicans have benefited from low voter turnout in the past. However, Professor Dixon warns that the impact of weather on turnout is likely to be small. She argues that motivated voters are likely to go to the polls regardless of the weather, making predictions uncertain.

Voter behavior

Recent changes in voting patterns in the U.S. may call into question the historical connection between bad weather and Republican electoral gains. A 2023 paper by Spencer Goidel and co-authors found that increased voter turnout since 2016 is no longer disproportionately in favor of Democrats. Instead, it has recently been shown that low voter turnout gives the Democrats an advantage.

This evolving dynamic suggests that Trump may now have a vested interest in seeing fair weather in critical swing states like Michigan and Wisconsin.

If turnout declines in these regions as expected, it could tip the scales in Harris' favor as working-class voters increasingly lean toward Republicans while college-educated voters support Democrats.