California company says cloud-seeding drones produced 19 million gallons of precipitation over Kenai Peninsula

By THE ALASKA STORY

Aug. 25, 2026 – A California weather-technology company says seven cloud-seeding missions flown over the Kenai Peninsula last weekend produced an estimated 19 million gallons of additional precipitation in roughly three hours.

Rainmaker Technology Corporation, an El Segundo-based company founded by Augustus Doricko, released a detailed report Monday describing drone operations conducted Aug. 22–23. The company characterized the Alaska flights as research and development intended to test and validate its drone-based cloud-seeding system.

According to the company’s self-published validation report, two “Elijah” drones identified as EL-151 and EL-153 flew seven coordinated missions as a low-pressure system strengthened over the Gulf of Alaska.

The drones released 19 silver iodide flares containing a combined 374 grams — less than one pound — of material. Silver iodide, commonly abbreviated AgI, has a crystalline structure similar to ice and is used to encourage the formation of ice crystals inside clouds containing supercooled water.

Rainmaker said the flights were conducted at elevations ranging from approximately 11,700 feet to 14,000 feet above sea level. Temperatures at the release altitudes ranged from approximately minus 5 degrees Celsius to minus 15 degrees Celsius, which the company said was suitable for activating the silver iodide.

Surface temperatures were warm enough that precipitation fell as rain in the valleys and snow over higher terrain.

Rainmaker said it identified seven separate “seeding signatures” using data from the PAHG NEXRAD radar serving the Anchorage and Kenai Peninsula region. Each radar signature appeared after one of the seven missions and moved downwind in a manner that the company said was consistent with the growth and descent of seeded ice particles.

The signatures appeared between approximately 17 and 40 minutes after the flares were released and, in some cases, remained visible on radar for more than an hour.

Using a 27-model quantitative precipitation estimate, Rainmaker calculated that its operations generated a mean of 57.6 acre-feet of additional precipitation, equivalent to about 18.8 million gallons. Its middle range of estimates was approximately 45.7 to 64.8 acre-feet, while the broader range extended from about 41.7 to 89.4 acre-feet.

The area receiving at least a trace of precipitation attributed to the seeding covered approximately 96 square miles, according to the company. Rainmaker estimated that the center of the affected area received more than one millimeter of additional precipitation.

Those figures are Rainmaker’s estimates, not measurements independently verified by an Alaska or federal agency.

The company acknowledged that some natural precipitation was already falling during the experiment and that atmospheric conditions were favorable but not ideal. The clouds contained both natural ice and intermittent pockets of supercooled liquid water, making it more difficult to separate naturally occurring precipitation from precipitation caused by seeding.

To account for the background precipitation, Rainmaker subtracted a baseline radar-reflectivity value before calculating the estimated additional water. The company also acknowledged uncertainty involving radar calibration, the placement of the manually drawn boundaries around the signatures and what happened to the precipitation as it fell below the radar’s lowest beam.

Rainmaker’s analysis is modeled on research from the 2017 Seeded and Natural Orographic Wintertime Clouds: The Idaho Experiment, known as SNOWIE. That National Science Foundation-supported project used aircraft, radar and ground instruments to identify and quantify snowfall attributable to cloud seeding.

A peer-reviewed study published in 2020 concluded that researchers had isolated radar-observable snowfall generated by cloud seeding during three Idaho events. That research was considered an important advance because earlier cloud-seeding studies often depended largely on statistical comparisons between seeded and unseeded storms.

Rainmaker applied a similar radar-based approach in Alaska, but its Kenai findings have not yet undergone peer review or independent third-party validation.

Cloud seeding does not create storms or manufacture clouds from clear skies. It attempts to extract additional precipitation from clouds that already contain the necessary moisture and temperature conditions. The results depend heavily upon the type of cloud, its temperature, the amount of supercooled water available and local wind patterns.

The technology has been used for decades in western states seeking to increase mountain snowpack and water supplies. Scientific studies generally indicate that glaciogenic cloud seeding can enhance precipitation when conditions are suitable, although calculating an exact increase from an individual operation remains difficult because no two natural storms are identical.

Rainmaker says it has been conducting flight testing and validation work in the Kenai Peninsula area since June. The company describes the Alaska operation as research rather than a commercial precipitation-enhancement program and says it operates with the applicable federal authorizations and aviation waivers.

Federal law requires weather-modification activities to be reported to the National Oceanic and Atmospheric Administration, although NOAA says it does not conduct, fund or oversee cloud-seeding programs. Aviation approval and other requirements may also apply when drones are operated at high altitudes or beyond the pilot’s direct line of sight.

Rainmaker said the Alaska flights represent a proof of concept and that it intends to continue refining its cloud-seeding platform during the coming winter.

The claim that the drones added approximately 19 million gallons of water over the Kenai Peninsula rests on Rainmaker’s own flight records and interpretation of publicly available radar data. The underlying cloud-seeding process is scientifically established, but the precise amount of precipitation attributed to this particular Alaska operation has not been independently confirmed.