SHOUT – Assessing the Utility of Unmanned Aircraft for Improving Operational Forecasts of Hurricanes and Tropical Cyclones

The NOAA Unmanned Aircraft Systems (UAS) program has begun the Sensing Hazards with Operational Unmanned Technology (SHOUT) project to evaluate the potential of high altitude, long endurance unmanned aircraft like the Global Hawk to improve forecasts of high-impact weather events and mitigate any degradations in the forecasts that might occur if there were a gap in satellite coverage. Improved forecasts of hurricanes and tropical cyclones are a major focus of the effort, and the first field phase of the project was conducted this past August and September to assess that goal. The NASA Global Hawk unmanned aircraft was instrumented with the Airborne Vertical Atmospheric Profiling System (AVAPS or dropsondes), the High Altitude MMIC Sounding Radiometer (HAMSR, a microwave sounder), the High-Altitude Imaging Wind and Rain Airborne Profiler (HIWRAP, a scanning Doppler precipitation radar), and the Lightning Instrument Package (LIP). Three 24-hour flights into Tropical Storms Erika and Fred were conducted from the NASA Wallops Flight Facility.

This presentation summarizes the mission goals, observations collected this year, utilization of the data, and preliminary assessments of data impact. Significant accomplishments this year include improved targeting of sampling using ensembles of forecasts from the Hurricane – Weather Research and Forecasting (HWRF) model, improved provision of real-time data to forecasters at the National Hurricane Center, and first-ever operational assimilation of Global Hawk dropsonde data in the HWRF model. Data impact is being evaluated through a combination of Observing System Experiments (OSEs) and Observing System Simulation Experiments (OSSEs). Initial results, while still limited, suggest the potential for positive impact on storm track and intensity forecasts.