Rainmaker, the weather modification startup focused on generating rain and snow through cloud seeding, announced today that it has raised $100 million in Series B funding. Investors including NOA VC, Upfront Ventures, DCVC, Lowercarbon Capital, and Dream Ventures participated in the round.
Rainmaker declined to share an updated valuation as part of the news. Prior to this round, the company had raised $50.3 million in venture backing.
Founded in 2023 (and dubbed “The hardest startup in America” by Fast Company), Rainmaker has developed a fleet of custom drones that can withstand harsh conditions in order to “seed” precipitation. During flights, the drones release silver iodide, an ice-attracting particle, into clouds with promising conditions. The silver iodide serves as a catalyst, helping turn the cloud’s water droplets or ice crystals into precipitation.
In recent months, the company says, it has made significant progress toward demonstrating the effectiveness of its seeding programs. Rainmaker says that it has data tying its flights to 145 million incremental gallons of fresh water: Its drones fly in programmed patterns, allowing researchers to distinguish their precipitation from naturally occurring precipitation. In August, test flights in Alaska’s Kenai Peninsula yielded 19 million gallons of precipitation over the course of three hours.
Augustus Doricko, founder and CEO of Rainmaker, views the Alaska testing as a breakthrough moment. “That [research campaign] represents a significant, precedent-changing shift in our capacity to produce fresh water at scale for the ecosystems, communities, and industries that need it across the Colorado River Basin, the Great Salt Lake, the rest of the dry and arid Western United States, and world over,” he says.
The new funding will support the expansion of Rainmaker’s research team, including radar meteorologists, machine learning specialists, and aerosol chemists. Rainmaker also plans to continue collaborating with outside research teams to validate its results.
Interest in weather modification is on the rise as climate change introduces new risks and concerns, from drought to increasingly powerful storms. Recast Systems, a newly launched competitor, is seeding clouds with an organic compound in Texas and New Mexico.
Doricko says Rainmaker has filed patents for multiple biodegradable seeding agents and is preparing to test them this winter.
If the company continues to make progress toward cloud seeding at scale, Doricko says he sees an opportunity to mitigate extreme weather, too. Hail storms, floods, tornadoes, hurricanes: It’s not hard to imagine that someone will be willing to pay to make events such as these less severe.
“We will be better situated than anybody in history to conduct these subsequent interventions,” Doricko says. They fit within his broader vision to “make Earth more habitable.”