December 1, 2025
The atmosphere doesn't stick to six-hour cycles. Your weather forecast shouldn't either.
Traditionally, global weather models run just four times a day, at 0z, 6z, 12z, and 18z (UTC). That means for most of the day, forecasts are already hours out of date. Although NOAA’s High Resolution Rapid Refresh (HRRR) model updates hourly, it only covers the U.S. and has a maximum horizon of 48 hours.
With WeatherMesh-5c, WindBorne introduces Continuous Forecasting, and the first continuously updated global weather model. WM-5c runs every 20 minutes, ingesting the latest observations—including a real-time stream of weather data from WindBorne's Global Sounding Balloons (GSBs)—to deliver forecasts that are always fresh and the most accurate. Instead of waiting six hours for the next update, WM-5c narrows the gap between what’s measured in the atmosphere and what’s reflected in the forecast down to 20 minutes.
Table of Contents
What is Continuous Forecasting
About WM-5c
Benchmarks
Historical Data Access
More Information
What is Continuous Forecasting
How We Do It
- Lightweight architecture: WM-5c’s efficiency means a 24-member ensemble runs in parallel on 8 GPUs in just 16 minutes.
- Independent assimilation: Unlike other operational AI models, which depend on ECMWF or NOAA analyses published every 6 hours, WM-5c is powered by WindBorne’s proprietary AI-based data assimilation (AI DA) system. We use our own AI DA not only because it enables us to ingest balloon observations, but also because it results in better forecast accuracy than using ECWMF’s and NOAA’s analyses.
- Proprietary observations: Our balloon constellation collects more in-situ atmospheric data than the National Weather Service every day, feeding WM-5c with a unique source of information at minimal latency.
Continuous Forecasting vs Alternatives
- Earlier forecasts: WM-5c forecasts are available up to 6.5 hours before ECMWF’s.