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(Provided by Gigafact.)

No.

Multiple studies show that cloud seeding does not increase rain or snowfall enough to trigger extreme flooding, and scientists say there is no evidence the practice contributes to weather disasters. 

Cloud seeding is a weather modification tactic where substances like silver iodide are released into clouds to encourage more rain or snowfall, often in drought-prone regions.

Data on the efficacy of cloud seeding varies. A 2018 report from the World Meteorological Organization, a United Nations agency that promotes international cooperation on atmospheric science and climatology, showed cloud seeding increases precipitation anywhere from 0% to 20% due to the weather’s natural unpredictability.

Researchers in Idaho found cloud seeding could add anywhere from .05 to .28 millimeters — roughly the thickness of fishing line — to snow accumulation.

Colorado, one of nine states actively cloud seeding, has had a weather modification permit program since 1972, with seven winter operations currently running throughout the state. 

See full source list below.

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References:

The claim that cloud seeding caused the Texas floods is untrue — and actively harmful, NPR, July 13, 2025. Source link.

Cloud Seeding Technology: Assessing Effectiveness and Other Challenges, U.S. Government Accountability Office, Dec. 19 2024. Source link.

Review of Advances in Precipitation Enhancement Research, Bulletin of the American Meteorological Society, Aug. 1 2019. Source link.

Quantifying snowfall from orographic cloud seeding, Proceedings of the National Academy of Sciences, Feb. 24, 2020. Source link.

September 2013 Floods, National Weather Service, accessed July 2025. Source link.

Weather Modification Program, Colorado Water Conservation Board, accessed July 2025. Source link.

Type of Story: Fact-Check

Checks a specific statement or set of statements asserted as fact.

Tyler has spent the last three years reporting on the environment, culture and local government in Colorado. Most recently, he spent time as a staff reporter and photographer for Boulder Weekly, where he covered the rapidly growing city of Longmont...