The Air Force’s 45th Weather Squadron (45 WS) provides comprehensive operational meteorological services to the Eastern Range (ER) and the Kennedy Space Center (KSC). These services include weather support for resource protection, pre-launch ground processing and day-of-launch operations for launches by the Department of Defense (DOD), National Aeronautics and Space Administration (NASA), and commercial launch customers, as well as Range Safety. To ensure safety of government personnel and the civilian population, the Safety Office of the Eastern Range must ingest weather data into physical models, which, in turn, assess the risk to safety of each operation.

Large vehicles such as the Air Force’s Titan IV rocket and NASA’s Space Shuttle are boosted by solid rocket motors which exhaust substantial amounts of hydrogen chloride (HCl) gas during a normal launch. The Titan IV also carries more than 400,000 pounds of liquid hypergol propellants, which could be released to the atmosphere in the event of a catastrophic failure. Ground operations involving fuel and oxidizer storage and transfer activities also pose a risk of toxic emissions. Restrictive federal and local guidelines force stringent human exposure limits for which accurate toxic hazard corridor (THC) predictions must be prepared to protect both on-base and off-base populations. These predictions support launch and ground operations, emergency response, and long-term planning (facility siting, launch availability studies, etc.). However, launch delays due to predicted THCs are increasingly becoming a concern. Any delay or postponement of a launch causes significant cost impacts.

The actual location of a THC is largely driven by meteorological conditions. Launch sites at the ER and KSC are located on coastal barrier islands subject to strong synoptic, regional, and local meteorological influences. Convergence between the sea breeze and the Indian River breeze often trigger thunderstorms over Merritt Island during the summer months. Outflow from these thunderstorms further complicates local wind patterns. Because of these complex wind flow patterns, THC predictions can be quite challenging.

To assess weather’s impact on launch operations, the 45 WS operates an extensive meteorological instrumentation network. One of the more recent systems added was a 915 MHz boundary layer Doppler Radar Wind Profiler (DRWP) network. This paper discusses the general method of toxic forecasting on the Eastern Range and presents one case illustrating the value of that 915 MHz DRWP network in predicting toxic exposure risk.