Stream interaction regions (SIRs) form when fast solar wind overtakes slow solar wind. These structures are long‐lasting and can corotate (i.e., a corotating interaction region) with the Sun, allowing for these structures to be observed by a warning buoy prior to encountering the Earth. When SIRs hit the magnetic field surrounding the Earth, they can trigger geomagnetic storms, which can negatively affect spacecraft and astronaut health, communications, and the electric grid. For this reason, predicting when an SIR may hit the Earth is an important problem in space weather. In our paper, we investigate the utility of deploying spacecraft to different locations around the Sun to act as a warning buoy system for these solar wind structures. For example, we find a 74.6% (46.1%) chance of predicting the arrival of an SIR at Earth within ±3 (±1) days after being observed at the Earth‐trailing Sun‐Earth Lagrange point, L5.
