Helene’s path not controlled by HAARP or radar | Fact check

A Sept. 27 Instagram post (direct link, archive link) includes a video of a weather radar map showing a hurricane moving up through Florida into the Southeast U.S. Blue flashing lights can be seen pulsating on the map around the hurricane.
“Who says ‘you can’t control the weather’” reads part of the post’s caption. “They cooked this one up – and push and pull it wherever they want using Nexrad (sic), Doppler and HAARP.”
The post was liked more than 4,000 times in 10 days.
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It is not possible to control the weather at a large scale, experts said. HAARP studies the ionosphere, and there is no known mechanism for affecting the weather from there. Doppler radars such as NEXRAD also cannot control storms, according to experts.
Hurricane Helene cut a swath of destruction through the Southeast, killing more than 200 people and causing more than $30 billion in losses after making landfall on Sept. 26.
It was the deadliest mainland hurricane in the U.S. since Katrina in 2005, spurring a rush of conspiracy theories about its origin. But the idea that it was created or directed by various technologies is unequivocally false, experts told USA TODAY.
“Weather systems – thunderstorms, hurricanes, cold fronts, winter storms – move based on the mid-latitude flow,” Katja Friedrich, a professor of atmospheric and oceanic sciences at the University of Colorado, said in an email. “In the case of Helene, there was this upper-level trough slightly to the west of the hurricane that made it move northwards or north-eastwards.”
Altering the large-scale flow of a storm would require changing the climate, such as the water temperature, she explained. That isn’t possible, nor is it the mechanism alleged to have been used in the post.
Instead, the post claims the storm was pushed around by Doppler radar, which is used to detect objects based on the way pulses of energy are reflected back to the radar. Signal strength, the time it takes to receive the return signal and other data points are analyzed to determine if the pulse pinged off a bird, a bug, a raindrop or something else.
The Next Generation Weather Radar, also known as NEXRAD, is a network of 160 high-resolution Doppler systems, operated jointly by the National Weather Service, the Federal Aviation Administration and the Air Force.
The most powerful Doppler radar systems can send out 750,000 watts of electromagnetic energy, according to the National Weather Service. Jen DeHart, a research scientist in Colorado State University’s Tropical Weather and Climate research group, told USA TODAY that is far less than what could push masses of air around.
“That energy does not move the storm around,” DeHart said in an email to USA TODAY. “Hurricanes are very large, and the water contained within a hurricane is immense. They are usually moved around by large-scale high-pressure or low-pressure systems. A radar does not transmit anywhere near enough energy to change the movement of a hurricane.”
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The post also claims that the High-frequency Active Auroral Research Program, also known as HAARP, modified the path of the storm. USA TODAY has previously debunked claims that HAARP affected storms.
HAARP uses a transmitter and advanced instruments to study the ionosphere, a layer of charged particles that separates the atmosphere and space. But there is no evidence the ionosphere can affect the weather.
The atmospheric pressure in the ionosphere is less than a millionth of the atmospheric pressure on the ground,” Toshi Nishimura, an associate professor at Boston University who studies the ionosphere previously told USA TODAY.
“It’s too light to create any appreciable disturbance in the lower atmosphere. It’s like an adult trying to push an aircraft carrier,” Nishimura said.
Hurricane Helene has generated an array of misinformation, with social media users sharing miscaptioned videos of other storms and AI-generated images of damage. False claims are also being shared about financial assistance from the federal government and a fundraising campaign announced by former President Donald Trump.
USA TODAY could not reach the social media user who shared the claim for comment.
Lead Stories also debunked the claim.
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