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What happened during the 1969 Hurricane Debbie seeding experiments in Project Stormfury?

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What Is Cloud Seeding? — weather modification Cloud seeding can produce an extra 5 to 15% of precipitation.

During the 1969 Project Stormfury experiments, Hurricane Debbie was seeded with heavy doses of silver iodide dropped from airplanes on August 18 and 20.

The results showed a decrease in maximum measured wind speeds of 31 percent and 15 percent on the two respective days of seeding. On August 19, the day between these flights, the storm reportedly reintensified. At the time, these findings were viewed with optimism because they aligned with predictions from a mathematical model of a hypothetical hurricane.

However, later scientific analysis suggested that the observed fluctuations in storm intensity were likely part of natural cycles rather than a direct result of the seeding. Due to these findings and the inherent difficulties in hurricane modification, Project Stormfury was eventually discontinued in 1983, and there are currently no active programs for hurricane modification.1