During 2009 and 2010, the DTC has worked with NCEP/EMC to port all capabilities of the operational Hurricane Weather Research and Forecasting (HWRF) model to community code repositories. At the same time, the DTC has developed a functionally-equivalent testing and evaluation infrastructure to allow running extensive HWRF tests to assess the forecast skill of new developments that can be considered for operational implementation.

The HWRF HNR2/HR20 test is the first comprehensive HWRF test conducted by the DTC. It had the goal of qualifying the DTC testing infrastructure and the community code by comparing them against a similar run conducted by EMC. Both the runs conducted at DTC, dubbed HNR2, and the runs conducted at EMC, dubbed HR20, correspond to the 2011 HWRF Operational Baseline, a starting point from which the code for the 2011 HWRF Operational Implementation was constructed.

As explained in detail in the Test Plan, an exact match between HNR2 and HR20 was not expected due to a few differences in how HNR2 and HR20 were configured. For example, HNR2 was run in a Linux cluster, while HR20 was run in an IBM P6. Nevertheless, the results indicate that the average forecast skill for the track and intensity forecast is virtually indistinguishable between HNR2 and HR20.