Point-Stat Tool: General

Point-Stat Functionality

The Point-Stat tool provides verification statistics for forecasts at observation points, as opposed to over gridded analyses. The Point-Stat tool matches gridded forecasts to point observation locations using several configurable interpolation methods. The tool then computes continuous as well as categorical verification statistics for the matched pairs falling inside the verification masking regions defined by the user. The categorical statistics generally are calculated by applying a threshold to the forecast and observation values. Confidence intervals, which represent a measure of uncertainty, are computed for most of the verification statistics.

New additions to the Point-Stat tool for METv2.0 include the verification of probabilistic forecasts and changes for the verification of wind direction. While verifying probabilistic forecasts will be covered in the section on Grid-Stat, we will perform the first step for the verification of wind direction in this section.

Point-Stat Usage

View the usage statement for Point-Stat by simply typing the following:

bin/point_stat

At a minimum, the input fcst_file in GRIB or NetCDF format (from PCP-Combine), the input obs_file in NetCDF format (output of PB2NC or ASCII2NC), and the configuration config_file must be passed in on the command line.

You may use the -ncfile command line argument to specify additional NetCDF observation files to be used. In order to produce anomaly statistics (SAL1L2 and VAL1L2 line types described in the MET User's Guide), you must specify a file containing climatological data using the -climo_file command line argument. You may also explicitly define the observation valid time window to determine which observations are used in the verification by using the -valid_beg and -valid_end command line arguments.