Viewing Nest and Running WPS with the WRF Domain Wizard

WRF Domain Wizard is a graphical user interface (GUI) which interacts with the WPS and enables users to easily define domains, create a namelist.wps, and run geogrid, ungrib, and metgrid. The GUI and a helpful online tutorial can be found at: http://wrfportal.org/DomainWizard.html.

Using the WRF Domain Wizard, a nest will be inserted into the parent domain of our "boston" test case. The nest specifications are:

  • horizontal grid spacing: 5 km
  • horizontal grid dimensions: 58x100
  • number of vertical levels: 38
  • central longitude: 71.00W [Standard Longitude in WRF Domain Wizard]
  • cnetral latiude: 42.00 N [True Latitude-1 in WRF Domain Wizard]
  • NAM input data: forecast cycle 2005012300 with output every 3 hours out to 24 hours

Before running the WRF Domain Wizard, make a new working directory for this case under your WRF/DOMAINS directory called boston_nest:

mkdir path-to-WRF/DOMAINS/boston_nest

To start-up the WRF Domain Wizard, open a web browser and go to: http://www.wrfportal.org/DomainWizard.html

To launch the program, click on the link under Run WRF Domain Wizard using Java Web Start.

A dialog box will appear which inquires what to open the WRF Domain Wizard with and "javaws" should be selected. If this option is not available, click on "Other" and point to where javaws is installed on your system.

Within the next dialog box that pops up, the WPS, Geography, and Domains directories need to be defined using the " ..." (browse) button on the right to select the correct directories. These should be as follows:

WPS Programs: path-to-WRF/WPS
Geography: path-to-WPS_GEOG-data
Domains: path-to-WRF/DOMAINS/boston_nest

After the above listed directories have been defined, click "OK".

Choose "New Domain" and click "Next".

Name the New Domain "wpsprd" and click "Next".

To start the domain selection, click and drag a box across the eastern half of the United States. Fill in the following values:

Projection Options : Type = Rot Lat-Lon (NMM).
Standard longitude = -71.00
True latitude 1 = 42.00

Click "Update Map".

Then fill in the specifics under Grid Options with the information provided for the coarse domain:

Horizontal dimension X = 56
Horizontal dimension Y = 92
Grid points distance (km) = 15
Geographic data resolution = "5m"

Click the "Nests" tab at the top of the dialog box. Click "New". Then fill in the boxes with the following values:

Nest Properties:

Parent ID = 1
Grid spacing ratio to parent = 3 (required to be 3 for the WRF-NMM)
Geographic data resolution = "2m".

Nest Coordinates:

Left = 17
Right = 36
Top = 64
Bottom = 31

Click "OK"

Your domains should look like:

Click "Next"

Under the Configure Preprocessor Variables for Ungrib and Metgrid heading select:

Grib Vtable Name = "Vtable.NAM"
Grib Files Dir : Select Dir = path-toGRIBdata/NAM
Grib Files : Select Files: click Add All >>
Grib Start Date = 2005-01-23 hh:mm:ss = 00:00:00
Grib End Date = 2005-01-24 hh:mm:ss = 00:00:00
Grib Interval (hr) = 3

Under the "Run Preprocessors to Generate Input Data Fields Required for WRF" heading click on:

"geogrid" under Run.

After successful completion of geogrid, two output static files will be created. Under View, click on "Output" to make sure the following files were created:

geo_nmm.d01.nc
geo_nmm_nest.l01.nc

Also under View , click on " Log" to look for "***successful completion of the program geogrid.exe***".

The next step is to click on:

"ungrib" under Run.

If ungrib completed successfully, intermediate files should appear in the domain directory with the file names in the form FILE: YYYY-MM-DD_HH . Under View, click on " Output" to look for the intermediate files and "Log" to make sure ungrib was successful.

The final step is to click on:

"metgrid" under Run.

If metgrid runs to completion, output files with the form met_nmm.d01. YYYY-MM-DD-HH: 00:00 will be created, where YYYY-MM-DD-HH: 00:00 refers to the date of the interpolated data in each file. Again, under View, click on "Output" to look for the output files and "Log" to make sure metgrid was successful.