SAN FRANCISCO — WindBorne Systems released the sixth version of its AI weather forecasting model, WeatherMesh 6, on June 1, 2026. The company claims the new model surpasses the accuracy of forecasts produced by the European Centre for Medium-Range Weather Forecasting (ECMWF) across several variables.
WeatherMesh 6 generates forecasts every hour, compared to the six-hour intervals of traditional models, and offers a resolution of 3 km in Europe and the continental U.S. WindBorne chief product officer Kai Marshland said WeatherMesh 6 “is as accurate five days out as a traditional forecast is the day before,” particularly on surface temperature measurements.
The company attributes the model’s performance to its proprietary data sources. WindBorne operates approximately 400 weather balloons in flight at any time, launched from 15 global sites, and sells that data to NOAA, the U.S. Air Force, and the U.S. Navy. Joan Creus-Costa, WindBorne’s head of AI, stated that direct ingestion of data from the company’s balloons and other sources is the key reason for improvements in WeatherMesh 6.
Founded in 2019 by a group of Stanford students, WindBorne initially built weather balloons to sell atmospheric data. The company began developing its own deep learning weather models in 2022. It raised $25 million in venture funding and was valued at $85 million in 2024. WindBorne sells its forecasts to investors and commodity traders.
CEO John Dean emphasized the strategic importance of owning a unique dataset. “I don’t understand, personally, the business model of being [an] AI based weather company without a data set advantage,” he told TechCrunch. He added that WindBorne has reduced its reliance on ECMWF’s initial conditions over time: “When we started doing [data assimilation] we were still very heavily reliant on ECMWF. I predict today, if we removed ECMWF’s initial conditions, we would actually still do pretty good.” Dean also said, “I’m not trying to invest a massive team into building a SaaS product, if the way people want consumer information two years from now is through an agent, right?”
No independent assessment of WindBorne Systems’s claims was available.