Setting up WXP Data Sources

WXP can run from either sample data or a live data stream. Sample data can be downloaded from the WXP web site:

http://wxp.vietorweather.com/sample

and download the data from the specific data directories (see local system setup for directory information).

Setting up the Ingestor

If live data is needed, WXP can access data from data feeds such as NOAAPort. WXP is ideally set up to access data from the LDM (Local Data Manager from Unidata). WXP will read LDM files directly but file naming is critical for easy access of data.

File Naming Conventions

WXP would like to see data distributed into directories based on date and data type. Typically, this means encoded data in a data directory, human readable advisories, warnings, forecasts in a text directory, model data in a model directory, and so on. In those directories, the files should be named as such:

{year}{month}{day}_{hour}{min}_{subtype}.{format}

The data should be organized by date, put in a subdirectory such as "20260921".

Examples of this would be:

WXP has a name convention file that can be modified to use nearly any naming convention. The default setup is to use the type of naming convention shown above.

LDM Setup

WXP has been tuned to work work with data streams distributed by the Unidata Local Data Manager (LDM). The LDM comes with a ldmd.conf file to configure upstream and downstream data flows. To save data, the LDM has a process names "pqact" which takes data from the LDM product queue and either feeds if to scripts or saves data to disk. Here is a sample pqact.conf file:

LDM pqact.conf file

To get this to save data to /data, add a symlink under ~ldm/var to point data at /data.

Decoding Data

WXP does need to decode certain types of data prior to use. This includes:

1. METAR/SYNOP data - This reformats the data into a common format so that a single program can access both data types.
2. Upper air data - This collapses the TTAA, TTBB, PPAA, etc products down into a single report for each upper air site. This is done for convenience.
3. NIDS data - This creates a mosaic of radar data for all radar sites.

There are scripts available to do this decoding available in the scripts/decode directory on the website. These include sfcconvert, synconvert, upaconvert, radmosaic.

Cron setup for automatic decoding

The cron program in Unix can be used to schedule decode scripts to run on a routine basis.

Here is a sample cron setup:

> crontab -l
*/5 * * * * /home/wxp/scripts/saoconvert
0,30 * * * * /home/wxp/scripts/synconvert
45 * * * * /home/wxp/scripts/upaconvert
*/5 * * * * /home/wxp/scripts/radmosaic


The decoders work in Universal time (UTC) but cron works on computer time. If the computer clock is on local time rather than UTC, then appropriate changes need to be made to these times relative to offset to UTC time and daylight savings time. The easiest solution to this is to run the computer on UTC time rather than local time or set the TZ environment variable at the top of the crontab:

• Go to next step: Setting Initial WXP Resource

Last updated: Oct 2026