HREF- High Resolution Ensemble Forecast model- A composite ensemble statistical model based on the NAM, HRRR RAP and HIREW versions, including the new HIRESW-FV3.

Some of the models that comprise the group, or ensemble, are time-lagged (previous runs) to give more time-based forecast continuity. The HREF is run four times a day, 00z 06z 12z and 18z. It becomes available about 3:10 minutes after its run is started.