This week is the second week of the PHI-HS experiment in the Hazardous Weather Testbed, in which two NWS forecasters are testing and evaluating the production of probabilistic hazard information (PHI) using AWIPS Hazard Services. One of the important aspects being tested as part of this experiment is how to collaborate the production of PHI across more than one NWS County Warning Area (CWA). During two of the real time and archived weather events the two NWS forecasters work during the week, each forecaster was assigned a specific area of responsibility. As storms moved from one area of responsibility to another, the forecasters used NWSChat and Hazard Services to collaborate in an effort to produce consistent, accurate PHI for these storms. Researchers from NOAA NSSL and GSD, NWS Warning Decision Training Dvision, University of Oklahoma CIMMS, and the University of Akron will evaluate results from the experiment to examine the various technical and procedural issues surrounding effective collaboration. This testing will not only help examine coordination issues related to PHI production, but could also help provide insight into warning and forecast collaboration issues more generally.