Global Atmospheric River Reconnaissance Underway for the 2025–2026 Water Year

January 16, 2026

As the 2025–2026 water year reaches full swing, AR Recon has entered a new phase of global coordination under the Global Atmospheric River Reconnaissance Program (GARRP), with expanded observations spanning multiple ocean basins across the Northern Hemisphere.

Florian Pappenberger, Director General of the European Centre for Medium Range Weather Forecasts, highlighted the significance of this expansion in a recent Financial Times article (PDF). “It’s fantastic that reconnaissance is going global. The Pacific programme has already substantially improved forecasting accuracy and I expect that this expansion will help to improve forecasting skill quite a lot more.”

This season, AR Recon missions continue over the North Pacific, while new flights are possible from Biloxi into the western Atlantic and the Gulf. During the week of January 12th, for the first time, there were two nearly concurrent flight missions for GARRP over both the Pacific and Atlantic oceans. On Thursday, January 15, there were two Air Force WC130-J flights over the Northeast Pacific, centered on 00Z January 16. Later that same day, NAWDIC’s flight season over the western Atlantic began with a HALO G550 mission centered near 12Z on January 16. This will hopefully be the first of many coordinated missions over the next month.

In parallel, the expanded Coordinated University Sounding Project for AR Recon (CUSP-ARR) enters its second season. This year, CUSP-ARR brings together 15 universities across North America to launch weather balloons during active storm periods, collecting high-resolution atmospheric data in data-sparse regions that experience, or are impacted by, AR landfall. CUSP-ARR radiosonde launches are directed by AR Recon mission control. In addition to forecast improvements, the program provides hands-on training for undergraduate and graduate students in observational techniques, data workflows, and participation in an international Research And Operations Partnership.

Together, these coordinated observations are designed to improve forecast skill by filling critical data gaps in regions where atmospheric rivers often form and intensify. This global approach supports the growing recognition that improving forecasts for floods, droughts, and extreme weather requires international collaboration.