- Climate
Texas floods not caused by cloud seeding or dam release, but likely worsened by climate change
Key takeaway
The floods in Texas on 4 July 2025 occurred in a region historically prone to flooding and were triggered by rainfall following extremely high levels of atmospheric moisture. Global warming increases atmospheric moisture, making extreme precipitation – like that which triggered these floods – more likely globally. There is no evidence that a dam release or cloud seeding caused the floods. Although cloud seeding was performed in Texas on 2 July 2025 by a start-up called ‘Rainmaker’, meteorologists and climate scientists explain that cloud seeding had effectively zero influence on the intense rainfall that caused the floods. Cloud seeding can only increase rainfall modestly over limited areas and only for short time spans; it cannot create clouds or storms that don’t already exist, nor can it cause extreme flood events like this one.
Reviewed content
Verdict detail
Incorrect:
The floods were caused by high precipitation due to an extremely high amount of water vapor over central Texas. Climate scientists explain it is not possible that recent cloud seeding could have caused the flooding, and in fact had almost zero influence on precipitation intensity.
Full Claim
Humans caused the Texas floods using cloud seeding, dam release, or other direct interference. It’s not possible that the floods would have happened otherwise.
Review
On 4 July 2025, heavy rainfall triggered catastrophic flash floods in central Texas, taking the lives of over 100 people, with many others reported missing.
The event unfolded in a region called ‘Texas Hill Country’ – also called ‘Flash Flood Alley’, as it is one of the most flood-prone areas in the U.S. due to its shallow soil, steep terrain, and high rainfall.
Following this tragedy, people online started spreading misinformation laced with conspiracies about what triggered the floods – ranging from cloud seeding to a dam release. Climate scientists and meteorologists quickly responded on social media, refuting misleading claims and offering clear scientific explanations in their place. But for many, this wasn’t enough.
As we’ve often seen, despite clear scientific explanations, bad actors seek to make money online by spreading conspiracies that go viral on social media. But as we’ve shown in past articles, they routinely miss the mark – often neglecting science and overstating human abilities to trigger disasters.
So what about this event? It turns out that a company called ‘Rainmaker’ did in fact do cloud seeding in Texas two days prior to the flooding, which raised suspicions on social media. The problem is that suspicions quickly turned to ‘conclusions’ without the support of any credible evidence, the telltale sign of conspiratorial – rather than scientific – thinking.
With that in mind, to investigate if recent cloud seeding – or other events – played a role in the flooding, we interviewed climate scientists with expertise in extreme weather events and cloud seeding to learn more.
No evidence that recent cloud seeding played any role in recent Texas floods
Before we begin – what exactly is cloud seeding? Cloud seeding is an 80-year-old technology which triggers rain or snowfall by dispersing small particles (usually silver iodide) in existing clouds. It’s no secret – in fact, the U.S. Government Accountability Office published a report on it in 2024.
It’s easy to see why people online are questioning if there were connections between Rainmaker’s recent cloud seeding and the floods, given they both happened in Texas two days apart. But coincidence alone does not guarantee a causal connection. In the same way that finding a cigarette butt in the ashes of a burnt-down house doesn’t mean it started the fire, cloud seeding occurring days before a flood event doesn’t mean it caused the flood.
So the next logical questions would be: did the cloud seeding particles stick around long enough to impact the storm two days later, and could cloud seeding even cause such a flood event?
To investigate those questions, we reached out to several climate scientists – all of whom explained that cloud seeing had effectively zero influence on the intense precipitation that triggered the floods.
One of these scientists, Dr. Bart Geerts, Professor at the University of Wyoming, has published many research papers on cloud seeding as a means to enhance precipitation. When asked if it’s possible that cloud seeding caused this flooding, Geerts explained:
Bart Geerts
Professor, University of Wyoming
“Definitively no. By their account (I spoke with the President of Rainmaker), they last seeded two days before the storm, on 7/1 [1 July 2025], and that was at least 30 miles away from the Guadalupe watershed. Even if they actively seeded during the storm event of the night of 3-4 July 2025, our cloud and AgI [silver iodide] resolving modelling work indicates that it would have made very little difference. […] Bottomline: our experience in various cloud regimes indicated that the impact will be very small.”
Science Feedback also posed this question to Dr. Daniel Swain, Climate Scientist at University of California Agriculture and Natural Resources, who studies extreme weather events like floods, extreme precipitation, and storms. Swain explained:
Daniel Swain
Climate Scientist, University of California Agriculture and Natural Resources, Los Angeles
“There is no evidence that cloud seeding activities played any role whatsoever in the Texas floods. In fact, it is highly implausible – from a meteorological perspective – that any actual or hypothetical cloud seeding activities would even theoretically be capable of causing a major flood event like this. […] Cloud seeding is the use of various methods to attempt to modestly augment natural precipitation from existing clouds and storms. It cannot create clouds or storms that do not already exist.”
Swain also pointed out that rain increases from cloud seeding are modest and very short lived, increasing rainfall by a maximum of 15% – but more typically around only 5%.
Finally, we asked Dr. Andreas Prein, Professor of High-Resolution Weather and Climate Modeling at ETH Zürich, who similarly explained:
Andreas Prein
Project Scientist, National Center for Atmospheric Research
“There is no scientific basis to expect that the cloud seeding had an impact on the severity of the flood. I heard that the last seeding was done two days before the event, meaning that the particles were already removed from the area before the flood event started. In general, the flood was related to the remembrances of a tropical storm that organized stationary thunderstorms over the region. Aerosol effects have secondary importance in such situations.”
In addition to those we interviewed, other scientists drew the same conclusions on social media. The day after the floods, meteorologist Matthew Cappucci tweeted, “Cloud seeding played ZERO role in deadly Texas floods. Rudimentary, basic physics explains that.”
Cappucci then point out why the sheer magnitude of this event far exceeds the capabilities of cloud seeding:
“it’s a small-scale thing. And it doesn’t create moisture; it just help[s] droplets in clouds bump into each other to form bigger drops that fall. You don’t spontaneously make 4 trillion gallons of water appear in Texas.”
For context, that amount of water would fill over 6 million Olympic swimming pools.
This is not the first time people have made claims that grossly overestimate the capabilities of cloud seeding. As Swain explained to Science Feedback:
Daniel Swain
Climate Scientist, University of California Agriculture and Natural Resources, Los Angeles
“It is worth noting that these incorrect claims of a link between cloud seeding and flood events are similar to those made during the record-breaking UAE rain/flood event a couple of years back; there was no evidence of a connection then or now.”
Substantial rainfall in central Texas triggered flooding – no evidence of a ‘dam release’
A video on TikTok went viral with over 500,000 views after claiming that ‘the floods were caused by a dam release because there is no footage of rainfall during the floods’. This is incorrect and misleading for several reasons.
Firstly, there are no reports that a dam release triggered this event. Climate scientists and meteorologists explain the event was triggered by heavy rainfall from high atmospheric moisture that remained after Tropical Storm Barry from the week prior.
Secondly, there is indeed footage of the rainfall during the Texas floods (see rain footage at 8:19 in video here, archived here). But video footage is not even necessary to prove it rained. Scientists do not estimate rainfall by watching videos online – they use data. Much of this data is freely available to the public to check for themselves.
For example, the National Atmospheric and Space Administration (NASA) recently shared satellite data which clearly shows high rainfall rates over central Texas on 4 July 2025 (Figure 1).
Climate change increases likelihood of extreme floods by increasing atmospheric moisture – future studies will determine contribution to this event
Some people online – like known misinformer Steve Milloy – are diminishing the idea that climate change could contribute to such an event. But the reality is that scientists have long-warned that weather extremes like these will increase as our planet warms (Figure 2).
In fact, scientists have high confidence that extreme precipitation events will increase globally as a result of climate change[1]. Scientists are confident about this projection because it is founded on a physical relationship which shows that, as our atmosphere warms, it holds more moisture. As Geerts explained to Science Feedback:
Bart Geerts
Professor, University of Wyoming
“There is a simple relationship between temperature and atmospheric humidity: the Clausius-Clapeyron (CC) relation predicts a roughly 7% increase in atmospheric water vapor for every degree Celsius of warming, which can lead to a similar increase in precipitation intensity. This is a scientific fact, not a debate.”
In other words, if our atmosphere was a sponge, the sponge would grow at a predictable rate as it warms up – thus allowing it to hold more water, and later precipitate that water under the right conditions. As Swain explained to Science Feedback:
Daniel Swain
Climate Scientist, University of California Agriculture and Natural Resources, Los Angeles
“These floods unfolded in an ambient airmass containing record (or near-record) water vapor over Central Texas. Climate change increases the amount of water vapor in air that is available to be converged into developing storms, and thereby increases the ceiling on how intense precipitation can become when conditions are otherwise favorable for torrential downpours (as they were in this instance)”
Scientists we interviewed explained that future studies of the Texas flood event will give them a more precise understanding of how much climate change contributed to this event.
Beyond this one flood, how will extreme precipitation increases affect future flooding? When it comes to climate change and flooding, evidence does not suggest there will be a universal increase in all flooding – but unfortunately, the ones that will increase are some of the worst kind. As explained by Swain:
Daniel Swain
Climate Scientist, University of California Agriculture and Natural Resources, Los Angeles
“There is not a 1:1 correspondence between increasing extreme precipitation events and changes in flood occurrence or severity. There is even some evidence that smaller floods may actually decrease in a warming world–while the very most extreme ones, like the Texas event, will increase[2]. But in general, there is more evidence that sudden and intense flash floods, specifically, occurring in urban areas and watersheds that respond very quickly to extreme precipitation are indeed increasing[3] with greater confidence than slower-developing and broader-scale river floods.
On a final note, it is important to acknowledge that there are two sides to a disaster: the physical aspects – which we have covered here – and the human aspects, like preparation and response. Geerts notes that:
Bart Geerts
Professor, University of Wyoming
“Aside from climate change, the immediate culprit here seems to be ineffective communication: the lack of a dedicated outdoor siren system, the lack of good cellphone reception, and the lack of requirement to have NOAA/NWS weather alerts active on their phones in that vulnerable area. But that is outside my expertise.”
With many people online – from politicians with no relevant expertise, to random social media users – sharing misinformation about extreme events, we encourage our readers to listen to scientists and experts to stay well-informed and prepared for future disasters.
Scientists’ feedback
1. There are claims that cloud seeding activities conducted by the company ‘Rainmaker’ were responsible for the floods in Texas on 4 July 2025. Is it possible for cloud seeding to cause such an event? If not, could it have any significant influence?
Bart Geerts
Professor, University of Wyoming
“Definitively no. By their account (I spoke with the President of Rainmaker), they last seeded two days before the storm, on 7/1, and that was at least 30 miles away from the Guadalupe watershed. Even if they actively seeded during the storm event of the night of 3-4 July 2025, our cloud and AgI resolving modelling work indicates that it would have made very little difference. With some funding, we are happy to quantify any residual effect of their seeding through modeling. We can also simulate various airborne cloud seeding scenarios during the storm, totally hypothetical scenarios, to quantify the potential impact. Bottomline: our experience in various cloud regimes indicated that the impact will be very small.”
Daniel Swain
Climate Scientist, University of California Agriculture and Natural Resources, Los Angeles
“There is no evidence that cloud seeding activities played any role whatsoever in the Texas floods. In fact, it is highly implausible – from a meteorological perspective – that any actual or hypothetical cloud seeding activities would even theoretically be capable of causing a major flood event like this.
Cloud seeding is the use of various methods to attempt to modestly augment natural precipitation from existing clouds and storms. It cannot create clouds or storms that do not already exist. Additionally, it only has a noticeable effect under a limited set of ambient weather conditions; in other settings, it would have essentially no effect at all. Additionally, modern cloud seeding techniques (even if used under optimal conditions) have only a very modest effect on precipitation that generally affects a relatively limited area. Most studies suggest that cloud seeding has the potential to increase precipitation by a maximum of ~15% under very specific conditions and over limited areas. In practice, the effect is typically much lower (more like ~5%) and there is even some scientific uncertainty whether it has much of a detectable effect at all given the considerable challenges in studying its effects (some studies have found an effect essentially indistinguishable from zero).
I have no specific knowledge whether this specific company was or was not operating at a particular time relative to the floods. I do know, however, that cloud seeding has a very time-limited effect (hours at most, not days, as the cloud condensation nuclei disperse or are rained out of the atmosphere). So even if the company were operating as soon as 24 hours in advance of the floods, there is essentially zero chance those activities could have influenced the event.
It is worth noting that these incorrect claims of a link between cloud seeding and flood events are similar to those made during the record-breaking UAE rain/flood event a couple of years back; there was no evidence of a connection then or now.
The U.S. Government Accountability Office (GAO) conducted a review of cloud seeding activities in late 2024; I was one of the contributors to this report.
In sum: it is far likelier that cloud seeding actually has an even smaller effect on precipitation than is widely claimed than it is that it had any measurable influence in amplifying the rainfall that caused this flood event.”
Andreas Prein
Project Scientist, National Center for Atmospheric Research
“There is no scientific basis to expect that the cloud seeding had an impact on the severity of the flood. I heard that the last seeding was done two days before the event, meaning that the particles were already removed from the area before the flood event started. In general, the flood was related to the remembrances of a tropical storm that organized stationary thunderstorms over the region. Aerosol effects have secondary importance in such situations.”
2. What role do scientists think climate change played in this event?
Bart Geerts
Professor, University of Wyoming
“The amount of water vapor in the air of central Texas was extremely high, and that fueled the heavy rainfall. The atmosphere over Texas Hill country contained up to 2.5 inches of precipitable water (PW) with water vapor transport contributions from the Gulf of Mexico and tropical east Pacific (remnants of hurricane Barry). PW is the vertically integrated water vapor, expressed as a depth of liquid if it were to fall out at once. It was also unusually warm. There is a simple relationship between temperature and atmospheric humidity: the Clausius-Clapeyron (CC) relation predicts a roughly 7% increase in atmospheric water vapor for every degree Celsius of warming, which can lead to a similar increase in precipitation intensity. This is a scientific fact, not a debate. The details of the extreme precipitation increase remain uncertain, e.g. where and how much.”
Daniel Swain
Climate Scientist, University of California Agriculture and Natural Resources, Los Angeles
“These floods unfolded in an ambient airmass containing record (or near-record) water vapor over Central Texas. Climate change increases the amount of water vapor in air that is available to be converged into developing storms, and thereby increases the ceiling on how intense precipitation can become when conditions are otherwise favorable for torrential downpours (as they were in this instance).
Formal attribution studies have not yet been conducted, and those will eventually be able to offer more robust estimates of the climate change contribution, but based on the current state of the science and other recent attribution studies regarding similar extreme convective (thunderstorm) rain events it is reasonable to estimate that the rain intensity was on the order of 10-15% greater due to historical warming.”
Andreas Prein
Project Scientist, National Center for Atmospheric Research
“The early attribution studies that I am aware of show that climate change clearly made the event more severe. The main reason is the warmer and moisture atmosphere under current climate conditions that causes increased extreme precipitation rates.”
3. How do scientists expect future climate change to influence these extreme flood events?
Bart Geerts
Professor, University of Wyoming
“Many studies have shown that extreme precipitation will become more frequent and more intense in a globally warmer climate, for instance [here][4] and [here][5].
Aside from climate change, the immediate culprit here seems to be ineffective communication: the lack of a dedicated outdoor siren system, the lack of good cellphone reception, and the lack of requirement to have NOAA/NWS weather alerts active on their phones in that vulnerable area. But that is outside my expertise.”
Daniel Swain
Climate Scientist, University of California Agriculture and Natural Resources, Los Angeles
“There is very strong agreement that climate change will increase the magnitude of most extreme precipitation events[6] across nearly all global land areas. This signal has already emerged across most of the globe, including in the United States generally (and specifically in Texas)[7], but will very likely emerge in other regions soon (including locations where precipitation is not increasing on average). It is also believed that short-duration convective precipitation extremes (i.e., those associated specifically with thunderstorms at at the upper end/beyond the level of intensity that was historically observed), as were responsible for the floods in this event, will increase at a faster rate that other precipitation extremes[8].
There is not a 1:1 correspondence between increasing extreme precipitation events and changes in flood occurrence or severity. There is even some evidence that smaller floods may actually decrease in a warming world–while the very most extreme ones, like the Texas event, will increase[2]. But in general, there is more evidence that sudden and intense flash floods, specifically, occurring in urban areas and watersheds that respond very quickly to extreme precipitation are indeed increasing[3] with greater confidence than slower-developing and broader-scale river floods.”
Andreas Prein
Project Scientist, National Center for Atmospheric Research
“Extreme precipitation events will further intensify into the future. Unfortunately, what we are currently seeing with ~1.2°C global warming is just a fraction of the changes that we expect later this century when we approach ~3°C warming and beyond.”
References:
- 1 – IPCC (2021) Sixth Assessment Report.
- 2 – Brunner et al. (2021) An extremeness threshold determines the regional response of floods to changes in rainfall extremes. Nature Communications Earth & Environment.
- 3 – Davies et al. (2024) A new conceptual model for understanding and predicting life-threatening rainfall extremes. Weather and Climate Extremes.
- 4 – Myhre et al. (2019) Frequency of extreme precipitation increases extensively with event rareness under global warming. Nature Scientific Reports.
- 5 – Thackeray et al. (2022) Constraining the increased frequency of global precipitation extremes under warming. Nature Climate Change.
- 6 – Fowler et al. (2021) Anthropogenic intensification of short-duration rainfall extremes. Nature Reviews Earth & Environment.
- 7 – Mascaro et al. (2025) Evidence of Emerging Increasing Trends in Observed Subdaily Heavy Precipitation Frequency in the United States. AGU Geophysical Research Letters.
- 8 – Lenderink et al. (2021) Scaling and responses of extreme hourly precipitation in three climate experiments with a convection-permitting model. Philosophical Transactions of the Royal Society A.
