Bad weather hurts Election Day turnout. Expanding mail and early voting can help, research suggests.

Inclement weather discourages voting on Election Day in the U.S., especially among young adults, people who don’t vote regularly and voters who tend to support Democrats, decades of academic research have found.

However, a recent paper published in Political Geography indicates rainy days in particular have less impact than they did before the COVID-19 pandemic. That’s largely because more people have started voting by mail and using other alternative voting methods.

A record number of voters cast mail-in ballots during the 2020 presidential election — 43%, up from 23% in 2016, an analysis from the MIT Election Data and Science Lab shows. In 2022, 32% of voters mailed their ballots.

The recent paper, which examines turnout in the swing state of North Carolina, finds that rain reduced Election Day voting there by 1 percentage point, on average, across the last four presidential elections. Rain also appears to affect voting in subsequent presidential elections, writes the author, Nick Turner, a principal economist at the Board of Governors for the Federal Reserve System.

“A novel finding of this paper is that absentee/early in-person voting increases in the following election in response to prior election rainfall,” writes Turner, who told The Journalist’s Resource he could not comment for this article.

Yusaku Horiuchi, a Dartmouth College professor who has studied weather and voting in the U.S. and Japan, described Turner’s findings as important. If more people can choose when they submit their ballots, weather will become less of a hurdle to voting, he wrote in an email to The Journalist’s Resource while traveling in Japan.

Horiuchi added that journalists should keep in mind that years of research demonstrate that rain and snow do not have a big impact on voter turnout.

“Given the extreme polarization of American politics, American voters may go to the polling stations regardless of the weather conditions,” he wrote.

Most studies that look at how U.S. voters respond to inclement weather focus on larger-than-normal amounts of rainfall. Studies examining natural disasters such as hurricanes and wildfires are less common.

As journalists review the research, it’s important they recognize that many studies present their results as percentage-point changes in voter participation. If you are unsure how a percentage-point change differs from a percent change, please read our tip sheet on the topic. We also created an infographic story to help journalists understand how to use these two math terms, which often are mistakenly interchanged.

1 percentage point

For every centimeter of rain — less than half an inch — the odds of voting drop about 1 percentage point, according to an estimate published last year in Electoral Studies. That estimate is based on a meta-analysis of data collected from 27 studies on weather and voter turnout written or published from 1993 to 2023.

Even small shifts in voter turnout in individual counties can alter the result of a close election, however. When a group of researchers looked at how weather affected U.S. presidential elections from 1948 to 2000 — including the very close presidential race in 2000 — they discovered that both rain and snow tended to benefit Republican candidates.

The heavier it rained or snowed, the better Republican candidates fared, the researchers write in the 2007 paper, “The Republicans Should Pray for Rain: Weather, Turnout, and Voting in U.S. Presidential Elections.”

“More precisely, for every one-inch increase in rain above its election day normal, the Republican presidential candidate received approximately an extra 2.5% of the vote,” write political scientists Brad T. Gomez, Tom Hansford and George A. Krause. “For every one-inch increase in snow above normal, the Republican candidate’s vote share increases by approximately 0.6%.”

If the weather in Florida had been drier on Election Day 2000, Democratic presidential candidate Al Gore would have won that state — and the election, the researchers note. A rainier day would have expanded Republican candidate George W. Bush’s lead.

“[I]t 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 researchers write.

Weather can make voting inconvenient

A 2018 study Horiuchi coauthored re-analyzes the data that Gomez, Hansford and Krause used and provides a more nuanced view of the issue.

Horiuchi and Woo Chang Kang, an associate professor of politics at Korea University, focus on the behavior of U.S. adults who don’t vote regularly. Compared with regular voters, so-called “marginal” voters tend to be younger and have lower incomes. They are much more likely to support the Democratic Party.

Horiuchi and Kang estimate that voter turnout falls by 1.07 percentage points when it rains 0.96 inches more than normal. They write that rainfall “decreases the Democratic candidate’s vote share by as much as 2.08% points, while it increases the Republican candidate’s vote share by 1.00% point.”

Horiuchi and Kang note that it is outside the scope of their study to pinpoint exactly why this happens. After reviewing research on human psychology and behavior, they hypothesize that inclement weather may help the Republican Party in two ways:

Marginal voters are more likely to forgo voting when it is less convenient — for example, when rain makes traveling difficult and waiting in line more uncomfortable.
Some voters who supported Democratic candidates in previous elections may choose a Republican candidate when the weather is poor.

“As documented in the literature of psychology and related fields, weather conditions are important determinants of social and economic behaviors of human beings,” Horiuchi and Kang write. “Inclement weather on the election day could affect voters’ moods and risk attitudes, which opens the possibility that weather conditions affect voters’ electoral choices as well.”

Severe weather and voting

Researchers have learned that severe weather has sometimes had less of an impact on voting than many people might expect.

Hurricane Katrina, one of America’s costliest natural disasters, hit New Orleans in August 2005, leaving 80% of the city flooded for weeks. When researchers looked at how the storm affected turnout for the city’s mayoral election in May 2006, they learned that flooding depressed voting. However, people living in the most flooded areas were more likely to vote than those in less flooded areas.

The group most affected — residents who experienced one foot of flooding — were 8.7 percentage points less likely to vote in the mayoral election than residents from areas that did not flood. People who lived in areas that experienced six feet of flooding were 3.7 percentage points less likely to vote, note political scientists Betsy Sinclair, Thad E. Hall and R. Michael Alvarez.

They write in their resulting paper, published in American Politics Research in 2011, that residents who experienced the most flooding might have been more motivated to participate in the election. Also, voter mobilization efforts might have targeted these residents more intensely.

Turnout fell in the Florida Panhandle after a Category 5 hurricane made landfall in October 2018, less than a month before the general election. But early, in-person voting offset some of the reduction, finds a 2023 paper in Political Research Quarterly.

Florida Gov. Rick Scott directed election offices in the eight counties that suffered the most damage to make it easier for their residents to vote prior to Election Day. In response, local election officials opened additional early voting sites, expanded the number of days people could vote early and expedited the processing of mail ballots, explain researchers William A. Zelin and Daniel A. Smith.

Zelin and Smith found that residents of those eight counties who had voted on Election Day in 2016 were 7.9 percentage points more likely to submit ballots at early voting sites in 2018, compared with similar voters in neighboring counties.

“We provide compelling evidence that general turnout is likely dampened when natural disasters strike, but that election administrators may be able to mitigate these effects by expanding access to convenience voting methods,” they write.

Climate change and elections

The meta-analysis published last year in Electoral Studies raises questions about how global warming might affect elections in the coming years.

If bad weather becomes more frequent and intense, weather on Election Day “will become increasingly consequential,” write authors Søren Damsbo-Svendsen and Kasper M. Hansen, political science researchers at the University of Copenhagen.

“Extreme weather at elections is thus one important way through which global climate change directly and tangibly interferes in politics,” they add.

Turner, the Federal Reserve economist, argues that alternative voting methods will prevent bad weather from reducing voter turnout. He stresses in his paper, published in April, that many earlier studies of weather and turnout were conducted when in-person voting on Election Day was the primary way to submit ballots.

His analysis suggests a rainy Election Day may actually boost turnout during subsequent elections by prompting people to use alternative voting methods. In North Carolina, bad weather later increased turnout by almost 2 percentage points, he estimates.

“One interpretation of these findings is that voters develop an aversion to casting their ballots in person after facing weather-related costs in the prior election and that the transition to alternate voting methods boosts the probability of voting overall,” Turner writes.

Bad weather dampens Election Day turnout. Studies suggest mail ballots and other alternative voting methods can help.

1 percentage point

Weather can make voting inconvenient

Severe weather and voting

Climate change and elections

Further reading

About The Author

Denise-Marie Ordway