Technical FAQs

Frequently Asked Questions for the Earth Prediction Innovation Center and Unified Forecast System Communities

We plan on supporting major commercial CSPs like Google Cloud, AWS and Microsoft Azure.  EPIC will also support Gaea, Hera, Jet, Orion and other non-commercial high-performance computing platforms.

We have a Cloud Cost Estimator tool available at that is updated frequently to assist in estimating costs.  UFS code is otherwise provided free of charge.

Information about how to use UFS code can be found at the resources listed below:

  • UFS Short-Range Weather Application 2.0.0

    Release Date: 06/23/2022

    Release Description: The SRW Application v2.0.0 includes a prognostic atmospheric model, pre- and post-processing, and a community workflow for running the system end-to-end. These components are documented within this User’s Guide and supported through a community forum ( New and improved capabilities for this release include the addition of a verification package (METplus) for both deterministic and ensemble simulations and support for four Stochastically Perturbed Perturbation (SPP) schemes. Future work will expand the capabilities of the application to include data assimilation (DA) and a forecast restart/cycling capability.


Previous releases are available to you, but we recommend using v2 for the latest and greatest features!

UFS Version 1.1.0 Release Users’ Guide


UFS Version 1.0.0 Release Users’ Guide

UFS Community Website:

UFS Weather Model Wiki –



NCEPLIBS Release Notes and Known Bugs –

NCEPLIBS-External Wiki –


UPP Version 9.0.0 Users’ Guide

UPP Version 1.1.0 Users’ Guide

UPP Version 1.0.0 Users’ Guide

Version 5.0 release (released in 2020 with the SRW App v1)

Version 4.0 release (released in 2019 with the MRW App v1)

Other Questions

While UFS application community releases do not currently support outputting satellite fields through the post-processing (UPP) utility, the stand-alone release of UPP can be utilized to output these fields if desired.

Stand-alone release of UPP

Things to consider when outputting satellite products:

  • Not all physics configurations are supported for outputting satellite products.
  • For regional runs, ensure the satellite field of view overlaps some part of your domain.


Note: Satellite output capabilities are available in the UFS-SRW develop branch, but are not yet supported to the community – stay tuned!

There are a few possibilities as to why a requested field may not be found in the UPP output.

  1. The field may be dependent on the model.
  2. Certain fields are dependent on model configuration, such as physics choices.
  3. A field may be missing from the model output that is required for outputting the requested field.

If it is suspected that UPP failed (e.g. no UPP output was produced), the best way to diagnose the issue is to consult the UPP log file created during runtime for any errors.

If using the run_upp script for a stand-alone UPP run, this log file, located in the /postprd directory, will be called upp.fHHH.out, where HHH refers to each forecast hour being processed.

For the UFS applications, these log files can be found in the experiment directory under log/run_post_f*.log for SRW or in the run directory for MRW.

UPP output is in standard Grib2 format and can be interpolated to another grid using the 3rd party utility wgrib2. Some basic examples can also be found in the UPP Users Guide.

If the desired variable is already available in the UPP code, then all that would be needed is to add that variable to the postcntrl.xml file and remake the postxconfig-NT.txt file that UPP reads.

postxconfig-NT.txt file

Please note that some variables may be dependent on model and/or physics used.

If the desired variable is not already available in the UPP code, then it can be added following the instructions for adding a new variable in the UPP users guide.

Add a new variable to UPP output