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Frequently Asked Question for the WRF Hindcast Project

Can I contribute data for a new sector?

Yes, we actively seek data contributors for new sectors.

10 active sectors are currently offered on our web site, covering about half of the western US. We have defined the remaining sectors for western US and seek contributors to generate the data for these sectors.

Data contributors can download a Docker container package from here which gives a fairly turn-key WRF platform. Registration with Agrineer.org is required to deliver the data to our server. Please visit this link to contact us.

Parties that are interested contributing data for other parts of the world should contact us. Our goal is to develop the necessary sector definitions (namelist.wps) for water stressed areas.

How can I monitor the progress of a WRF run?

There are two phases to a WRF run, the WPS setup and the actual WRF program. The WPS setup will report to the wrf/log/SECTOR.log file. The WRF program progress can be monitored with the "tail" program on the file rsl.error.0000.

For example, in a terminal
$ tail -f /wrf/sectors/SECTOR/wrf/rsl.error.0000

How can I look/read the WRF run output files?

The output files are in NetCDF4 format from UCAR and can be viewed graphically with the "ncview" program from David Pierce at Scripps Institution of Oceanography. The "ncinfo" program (UCAR) gives meta data in text output. Many language API's are available which can read the NetCDF4 format, such as Python netCDF4 and the gdal class from osgeo package. Octave/Matlab also have functions which can read the NetCDF4 files.

Why do WRF runs default to yesterday?

Our WRF runs use reanalyzed forcing files from the Global Forecast System model. Reanalyzed means that the forcing files use available sensed data (satellite, balloons,etc.) from the past and not the predicted values used in forecasting. So, the runs must wait for a day for the reanalyzed files to be made available.

It is possible to run the WRF/SME in forecast mode and it would be useful for predictive purposes, but would be less reliable than the hindcast mode.

Why do the GFS input files go from 06:00am to 06:00am the next day for the WCONUS sectors?

The Global Forecast System forcing files carry a UTC time stamp. Sectors that are exactly 6 hours from UTC will have a 12:00am to 12:00am daily period, sectors that are 5 hours from UTC will have a 01:00am to 01:00am period and sectors that are 7 hours away will have a 11:00pm to 11:00pm period. All times are standard with no adjustments for Daylight Savings. Attempts to specify starting hour starts failed in WRFV3, and have not been tried yet in WRFV4.