If you meet all the [requirements](mar-forecast-intro) to set up a MAR-based weather forecast, follow the next steps carefully to first set up a folder hierarchy that will act as the backbone of the forecast. This hierarchy will indeed provide all the base components of the so-called **operational chain**, i.e., the sequence of practical operations that are run to prepare and run MAR forced by [ERA5T](https://forum.ecmwf.int/t/release-of-era5t/1136) or [GFS](https://en.wikipedia.org/wiki/Global_Forecast_System) one day at a time, the latter corresponding to an actual weather forecast.
If you meet all the [requirements](mar-forecast-intro) to set up a MAR-based weather forecast, follow the next steps carefully to first set up a folder hierarchy that will act as the backbone of the forecast. This hierarchy will indeed provide all the base components of the so-called **operational chain**, i.e., the sequence of practical operations that are run to prepare and run MAR forced by [ERA5T](https://forum.ecmwf.int/t/release-of-era5t/1136) or [GFS](https://en.wikipedia.org/wiki/Global_Forecast_System) one day at a time, the latter scenario corresponding to an actual weather forecast.
1. On your target computer (i.e. where the forecast will run), e.g. a cluster, create a new directory at a suitable location to store the software and main resources of the operational forecast chain. **This directory must be permanent** as it will both contain the main software, the `MARsim` archives used for the forecast as well as logs written by various parts of the operational chain. This directory will be subsequently refered to as `$DIR`.
1. On your target computer (i.e. where the forecast will run), e.g. a cluster, create a new directory at a suitable location to store the software and main resources of the operational forecast chain. **This directory must be permanent** as it will both contain the main software, the `MARsim` archives used for the forecast as well as logs written by various parts of the operational chain. This directory will be subsequently refered to as `$DIR`.
