President Biden is navigating a politically fraught path on climate change after last weekend’s deadly tornadoes, stopping short Monday of directly blaming global warming for the disaster but emphasizing the storms’ extreme nature and ordering officials to get more definitive answers.

Biden, facing an unusual series of violent weather events during his first year in office, has been forced to change the way presidents have long dealt with natural disasters. A task that once involved calling local leaders, offering aid and consoling victims — all things Biden has done — has expanded to far more politically sensitive terrain.

Scientists are drawing clearer lines between global warming and destructive weather — often prompting Biden to warn of the urgent need to address rising temperatures. And some climate activists say the tornadoes underline the urgency of swift action. But Republicans are eager to pounce on any exaggeration of climate change’s impact, putting pressure on Biden not to get ahead of what is verifiable.

“We have to be very careful — we can’t say with absolute certainty that it was because of climate change,” Biden said Monday after officials briefed him on the tornadoes.

But he added, “What is certain: It is one of the worst tornado disasters we’ve had in the country. And the second thing that’s certain is that it is unusual. It is unusual how it happened, how many places it touched down, and the length of the path. So that’s all I’m prepared to talk about right now.”

Biden on Wednesday plans to visit Kentucky, where tornadoes killed at least 74 people. At least 14 more were killed in other states. Kentucky leans heavily conservative and is the home of Senate Minority Leader Mitch McConnell (R), a vocal critic of Biden’s climate agenda.

McConnell did not mention climate change in a floor speech Monday on the tornadoes.

Biden said he has ordered the Environmental Protection Agency and other departments to delve more deeply into whether climate change is responsible for the tornadoes or contributed to their ferocity. Although the precise connection between climate change and tornadoes is not certain, experts have said that higher temperatures could intensify these violent storms.

The recovery efforts come at a moment when climate change is at the center of Biden’s domestic agenda. He is trying to push a bill across the finish line on Capitol Hill that, among other things, would make historic investments in fighting climate change. His administration is also promoting a new infrastructure law that makes large investments in a vast network of electric-vehicle charging stations.

Vice President Harris traveled to Maryland on Monday to focus attention on the administration’s push to electrify the country’s transportation system. “There can be no doubt: The future of transportation, in our nation and around the world, is electric,” Harris said.

Without directly referring to the tornadoes over the weekend, Harris noted that a reason for the administration’s urgency on climate is the extreme weather that is increasingly gripping the country, from wildfires to tornadoes to floods.

“Across our nation, rising sea levels are flooding streets,” Harris said. “Wildfires are burning out of control.”

Scientists and environmentalists describe climate change as an existential threat that could cause untold harm to humans and other species if far-reaching changes are not made fast, and Biden has made tackling this problem a centerpiece of his domestic and foreign policy blueprints. But Republicans are quick to criticize Biden’s climate agenda as an overreaction to an exaggerated problem that will cost jobs and raise prices.

Robert Stavins, director of Harvard University’s Environmental Economics Program, said relying too heavily on extreme weather to make the case for climate mitigation can backfire, because opponents can point to stretches of fair or frigid weather to argue that action isn’t needed.

He recalled a Republican senator organizing activists to stand outside in Washington during a snowstorm with signs that read, “Honk if you think global warming is a hoax.”

“One has to be very careful, in my opinion, of getting too far out in front of these claims, because it can come back to haunt you,” Stavins said.

For many years, presidents dealt with natural disasters as “Acts of God,” spending little time litigating their causes and devoting most of their energy to dealing with the aftermath.

But over the past decade, experts have been able to more definitively attribute the strength of storms to changes in the climate, strengthening the hand of politicians who are urging policy changes, said Paul Bledsoe, who served as climate adviser to the Clinton White House.

“We didn’t have that in the 1990s when we were trying to warn the American public that this public safety crisis was coming,” said Bledsoe, who is now a strategic adviser at the Progressive Policy Institute. Even during President Barack Obama’s tenure, it was difficult to conclusively draw the connections between extreme weather events and warming temperatures, he said.

Still, the science connecting tornadoes to climate change is limited, he said, which helps explain why Biden has stopped short of attributing the recent tornadoes to the planet’s warming.

Nonetheless, a volatile issue has become part of the response to natural disasters, an area that had largely been free of politics. Biden in particular has sought to stress unity and empathy after such tragedies, but even his relatively limited statements on climate change in response to reporters’ questions have drawn attacks from the right.

On other occasions, Biden has been blunt, warning that the country faces a “code red” moment on climate. “We know that decades of forest management decisions have created hazardous conditions across the Western forest, but we can’t ignore the reality that these wildfires are being supercharged by climate change,” he said in remarks after observing areas destroyed by wildfires earlier this year.

White House press secretary Jen Psaki stressed that many communities of all ideological stripes are affected by severe weather events fueled by climate change. But she signaled that Biden’s visit Wednesday would be more about providing comfort to those hit hardest by the recent tornadoes.

“That visit is really about him receiving an update of the work that’s happening on the ground, hearing directly from leaders on what they need more from the federal government, if anything,” she said, adding, “He’s not going to give a major speech while he’s there.”

The president is also likely to stress the need to support the victims and their families. On Saturday, as news of the devastation was emerging, Biden stressed the human costs to those who had lost their homes and worse.

“My heart aches for those people right now, including the rescuers,” he said. “Everything is gone, from the baptismal photograph to the wedding picture to the picture of your oldest daughter in a ballet. It’s profound. It’s profound.”

Politicians like Biden are becoming more vocal about extreme weather just as the public is expressing more concern. A September survey conducted by the nonpartisan Pew Research Center showed that 67 percent of Americans said extreme weather events are happening more often than in the past, including majorities across all major regions of the country.

A 2019 poll from The Washington Post and the Kaiser Family Foundation found that 63 percent of people who said their area had been affected by severe storms, droughts or extremely hot days identified climate change as a “major factor.”

Still, wider acceptance of the impact of climate change does not necessarily mean that Americans will back mitigation efforts in large numbers. Many Republican elected officials and even some Democrats have resisted aggressive efforts to curtail emissions, arguing that doing so comes at the expense of workers in industries involving fossil fuels.

They include Sen. Joe Manchin III (D-W.Va.), whose state depends heavily on coal. Manchin has emerged as a key holdout with the potential to make or break a massive social spending plan that would enact the biggest clean-energy investment in U.S. history. Manchin has recently voiced concerns about other aspects of the bill, most notably its overall size and potential effect on inflation.

Biden said Monday that he was not intent on using the recent storms or climate change to twist Manchin’s arm during a high-stakes conversation with the moderate Democrat.

“No, I’m not going to make that argument with him about this. Look, Joe understands,” said Biden of the senator. “He’s been through some real disasters in West Virginia.”

Some liberal activists seized more aggressively on the tornadoes to pressure lawmakers to pass the social spending bill.

“This climate disaster is about our electeds failing us, choosing to water down and delay climate bills instead of investing in infrastructure that will keep people safe,” Varshini Prakash, executive director of the Sunrise Movement, said in a written statement. Prakash added that the plan “must pass. It is the bare minimum.”

Revving up the country’s battle against climate change — after four years under President Donald Trump, when that battle was largely abandoned — has been a central theme of Biden’s presidency. The climate challenge is one of four major crises he pledged to tackle upon taking office, along with the coronavirus pandemic, the economy and racial justice.

In February, the United States officially rejoined the Paris climate accord, a major international agreement from which Trump had withdrawn. Biden also took a leading role at a recent international climate summit in Glasgow, Scotland.

Beyond that, climate has been a pillar of Biden’s two highest-profile legislative packages: the infrastructure law that recently took effect and the social programs bill that he hopes to push through in coming weeks.

“We all know everything is more intense when the climate is warming — everything,” Biden said Saturday. “And obviously it has some impact here, but I can’t give you a quantitative read on that.”

Scott Clement contributed to this report.