This use case takes the PB2NC tool and combines it with the Ensemble-Stat tool, analyzing multiple forecast fields and producing ensemble relative frequencies.
Optional: Refer to the METplus Config Glossary section of the METplus Users Guide for a reference to METplus variables used in this use case.
-
Review the use case configuration file: EnsembleStat_fcstHRRRE_obsHRRRE_Sfc_MultiField.conf
Open the file and look at all of the configuration variables that are defined.
Note that in this use case, the PB2NC GenEnsProd, and EnsembleStat tools will be called:
Another important aspect of this use case is its use of lead times. While INIT_BEG and INIT_END are the same, there are three leads listed:
And that controls what files are looked at in the EnsembleStat call:
{init?fmt=%Y%m%d%H}/postprd_mem0002/wrfprs_conus_mem0002_{lead?fmt=%HH}.grib2
Given the lead times and INIT time, the tools will loop over the following valid times:
-
20180709 at 12z
-
20180709 at 13z
-
20180709 at 14z
The run time for this use case is expected to be longer, due to the multiple lead times, two MET tools, and 6 variables at multiple thresholds being analyzed.
-
Run the use case:
${METPLUS_BUILD_BASE}/parm/use_cases/model_applications/short_range/EnsembleStat_fcstHRRRE_obsHRRRE_Sfc_MultiField.conf \
${METPLUS_TUTORIAL_DIR}/tutorial.conf \
config.OUTPUT_BASE=${METPLUS_TUTORIAL_DIR}/output/Ensemble
METplus is finished running when control returns to your terminal console and you see the following text:
-
Review the output files:
You should have two directories of interest:
- EnsembleStat
-
rap
These two directories correspond to the output directories for two of the tools in the configuration file:
Take a look at the output from PB2NC first:
You'll see 3 output files, corresponding to the three lead times that were run. These files were read in by the EnsembleStat call and processed for statistics. Taking a look at those files we see a lot of output:
Each lead time is responsible for producing 8 files, for a total of 24 files. These were all requested with the ENSEMBLE_STAT_OUTPUT_FLAG options, with the exception of the .stat and .nc files.
-
Compare the netCDF output to the .stat output:
To better understand the difference between the FCST and ENS entries in the configuration file used by the EnsembleStat and GenEnsProd tools respectively, take a look at the netCDF file for the first lead time (0):
You'll notice that the majority of the extensive variables listed have the words "ENS_FREQ". This is because those variables were called with the ENSEMBLE_FLAG options: GenEnsProd will provide a summary of all fields requested across the ensemble for those ENS_VAR<n> variables.
Now look at the .stat file for the same lead time:
In the VX_MASK column, the four mask files requested are listed, along with the various line types that were requested (listed in the LINE_TYPE column). What's important to note is the lack of variable variety that was present in the netCDF: in fact, the only variable listed is TMP at the Z2 level. That's because in the configuration file, only 1 variable was requested with the FCST_VAR<n> options, and only those variables will be used for verification.
