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Why is cloud seeding often used to increase mountain snowpack?

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

Cloud seeding is used to increase mountain snowpack by introducing substances, such as silver iodide, into supercooled clouds—clouds composed of water droplets at temperatures below freezing.12

These substances act as ice nuclei, providing a surface around which water droplets can evaporate and deposit as ice crystals. As these crystals grow by attracting additional water droplets, they become heavy enough to fall as snow. This process is specifically employed over mountainous regions, such as the western United States, to enhance winter water supplies.12

While some studies suggest that seeding can increase precipitation from supercooled clouds by 10 to 20 percent under optimal conditions, the practice remains a subject of scientific debate. The effectiveness of cloud seeding is highly dependent on specific meteorological conditions, and in some instances, it may be ineffective or even lead to decreases in precipitation. Because precipitation is naturally variable, it is difficult to definitively quantify the exact impact of these operations.12