This dataset show the generalized coverage area (as of October 2014), of High Frequency (HF) radar systems across the US. HF radars measure the speed and direction of ocean surface currents in near real time. These radars can measure currents over a large region of the coastal ocean, from a few kilometers offshore up to 200 km, and can operate under any weather conditions. They are located near the water's edge, and need not be situated atop a high point of land. Dozens of institutions own and operate HF radars within the United States, and a majority are coordinated through the US Integrated Ocean Observing System. Ocean surface current data from these radars are shared on national servers -- the National Data Buoy Center and Scripps Institution of Oceanography -- who deliver the data to anyone who needs it. A process is currently underway to further define the spatial footprint of each radar based on local factors such as nearby obstructions, local wind-wave environment, etc. When available, this data will be integrated into MarineCadastre.gov. In the meantime, if specific information regarding a local radar system is required, please contact Dr. Jack Harlan, Project Manager for the HF Radar Ocean Remote Sensing, US IOOS Program Office.