“Cloud seeding technology can reliably produce rainfall during drought conditions.”

The model result indicated that cloud-seeded technology is effective over Ethiopia when the daily resultant wind speed is less than 1.5 m/s and cloud base height (CBH) is less than 1700 m. During the spring season, PR is found 1.31 which is greater than 1, the seeding is effective, and during autumn is slightly effective. The spatiotemporal analysis showed effectivity rates like 29.16% in April 2021 and 37.50% in May 2021 under specific conditions.

While many smaller scale efforts occurred attempting to assess the efficacy of cloud seeding for purposes of precipitation enhancement, the SNOWIE research project was the first to demonstrate 'unambiguous' evidence that cloud seeding can produce winter precipitation. Cloud seeding authorized by the Idaho Water Resource Board (IWRB) is used during the cold season to augment high elevation snowpack, a critical source of water supply for the state.

Research reviewed by the US Government Accountability Office (GAO) suggests that cloud seeding may increase precipitation by up to 20 percent under optimal conditions. However, proving its effectiveness remains difficult due to limited data and the unpredictable nature of weather, and success depends heavily on the presence of the right types of clouds, which can limit opportunities for implementation.

Most studies suggest cloud seeding may increase precipitation by only 5-15%, compared to what would happen without cloud seeding. It’s difficult to say exactly how well cloud seeding works, because weather naturally varies a lot, and exact rainfall amounts are difficult to predict. Based on what we know about how clouds and rain form, cloud seeding doesn’t cause a significant increase in precipitation.

DRI's cloud seeding projects are conducted in an environmentally safe manner, increasing the precipitation formation efficiencies of passing clouds to support the water needs of local communities and ecosystems. DRI's team of scientists and technicians work year-round to design, maintain, and operate successful cloud seeding projects for state, local, and federal partner agencies. DRI's cloud-seeding program supplements the precipitation in existing storms, which can help alleviate the impacts of drought in targeted areas.

Its effectiveness depends heavily on environmental factors. For example, if clouds don’t contain enough moisture to begin with, cloud seeding won’t generate rain. Wind patterns, temperature, and local terrain also play a role; under the wrong conditions, even the most advanced seeding techniques can fall flat.

Cloud seeding enhances precipitation by working alongside natural atmospheric processes in clouds capable of producing precipitation, but it cannot create clouds, nor is it effective on large-scale storm systems that are efficiently producing precipitation. Experts suggest cloud seeding can squeeze out an extra 5 to 15 percent of rain, if successful.

Cloud seeding has evolved into a potential solution to droughts, a tool for firefighting, and a catalyst for weather modification. However, its reliability during drought conditions is not specified, with general claims of potential but noting pitfalls.

Although not a panacea for drought-stricken regions, cloud-seeding can increase seasonal precipitation by about 10%. It can only be used to supplement precipitation in an existing storm and cannot be used when there are no storm clouds to squeeze additional moisture from.

Recent research suggests that the decades-old approach can be effective, at least when seeding for snow, with a 2020 study demonstrating unambiguously that cloud seeding can increase snowfall. However, experts agree that cloud seeding should not be thought of as a response to drought, as in a drought there are likely to be fewer seed-able storms, and even optimistic estimates show only around a 10 percent increase in precipitation.

The results of about 70 years of research into the effectiveness of cloud seeding are mixed; most scientific studies aimed at evaluating the effects of seeding cumulus clouds have shown little to no effect, while seeding wintertime orographic clouds has shown increases in precipitation. The percentage increases in precipitation are small, and it's difficult to tell when snow or rain fell naturally and when it was triggered by seeding.

The World Meteorological Organization (WMO) states that evidence from randomized trials shows cloud seeding can increase precipitation by 5-15% under optimal conditions, primarily for orographic winter clouds, but results are statistically inconclusive for rain enhancement in summer cumulus clouds or drought-specific scenarios due to high natural variability.

Recent research in Israel reveals that the common practice of cloud seeding with materials such as silver iodide and frozen carbon dioxide may not be as effective as it had been hoped. In the most comprehensive reassessment of the effects of cloud seeding over the past fifty years, new findings have dispelled the notion that seeding is an effective mechanism for precipitation enhancement.