A pilot Airborne Snow Observatory (ASO) in the Weber Basin is producing preliminary snow-pack mapping that closely matches existing SNOTEL point observations, project representatives told the Weber River Watershed Council on Nov. 26, while stressing that forecast products require additional validation.

An ASO representative said the pilot — funded in part by a Bureau of Reclamation grant and basin partners — covers roughly 870 square miles focused on upper headwaters, and that a snow‑free flight completed Sept. 25. The team reported preliminary comparisons of ASO snow depth to SNOTEL readings showing differences of only a few centimeters in places and an estimated change on the order of tens of thousands of acre‑feet between two surveys, though the presenter cautioned those figures are still under correction and validation.

"We're still waiting on forecast results, which is undergoing some correction and validation at the moment," the presenter said. "We're expecting those within the next week or two." The presenter added that ASO uses lidar and imaging spectrometers to create snow‑on and snow‑free digital elevation maps and then models snow water equivalent (SWE) via a snowpack model that feeds into the WRF‑Hydro runoff forecast model.

The team described the pilot’s objectives as producing a near‑real‑time basinwide picture of seasonal snowpack, improving runoff forecasting for water managers and assessing whether ASO-derived products are cost‑effective for larger operational use. The presenter said the pilot cost is about $1.8 million over three years and that a final pilot report will be delivered in 2027.

Council members asked about flight timing, gauge selection and data ownership. The presenter said ASO technically owns the raw data but funding partners receive access, and staff will follow up with a gauge list and data‑sharing details.