MADIS Distribution Services
MADIS subscribers have access to an integrated, reliable, and easy-to-use database containing real-time and archived observational datasets plus real-time surface analyses grids. To gain access to the MADIS observational database, please fill out a data application form. This will help the MADIS team assess your needs and provide you with the correct data restriction access.
MADIS ingests data files from NOAA data sources and non-NOAA data providers, decodes the data and then encodes all of the observational data into a common format with uniform observation units and time stamps. Quality control checks are conducted and the integrated data sets are stored in the MADIS database with a series of flags indicating the quality of the observation from a variety of perspectives (e.g. temporal consistency and spatial consistency), or more precisely, a series of flags indicating the results of various QC checks. MADIS users and their applications can then inspect the flags and decide whether or not to use the observation.
MADIS data is made available to the enterprise using multiple data transfer protocols via the Internet:
- real-time access
- archive of saved real-time access (ftp only)
- data delivered in netCDF file format
- List of mesonets currently available*
- Station locations and real-time data for all of the mesonets
- Instructions on how to filter out stations outside of your geographic area from national-scale mesonets
- Accumulated precipitation type table for "super mesonet sampling" customization
- Applications Program Interface (API)
- Web Services
- Text/XML Viewer
- Meteorological Surface
- Hydrological Surface
- Graphical Displays
The datasets in the MADIS database are stored in netCDF files.
This is the file format that is used when users request MADIS data using either ftp or LDM protocols.
MADIS supplies LDAD-compatible CSV files for many different mesonets.
Note that you don't have to select any of the dataset buttons in the
data application form, just put "LDAD mesonet CSV" data into
the remarks section.
Once you subscribe, we will set you up with an account on our ftp server (even if you're an ldm user). Once you log onto the server, you'll find README instructions for each mesonet, the necessary LDAD metadata files (*Station.txt, *.desc), and any necessary scripts and LDAD preprocessors. The station tables are updated weekly.
Also, where applicable (such as for GPSMET integrated precipitable water vapor), the README file will explain how to customize AWIPS to display additional variables that aren't part of the baseline AWIPS system.
- MADIS provides an Application Program Interface (API) and related utility programs, which allow easy access
to MADIS observations without having to develop a program for reading netCDF files. The API allows each user to specify station and
observation types, as well as QC choices, and domain and time boundaries. Many of the implementation details that arise in data
ingest programs are automatically performed. Users of the MADIS API, for example, can choose to have their wind data automatically rotated
to a specified grid projection, and/or choose to have mandatory and significant levels from radiosonde data interleaved, sorted by
descending pressure, and corrected for hydrostatic consistency. The API is designed so that the underlying format of the database is
completely invisible to the user.
Users wanting access to MADIS data via web services are provided with data viewers and graphical displays.
This service provides access to both public and restricted text, csv, or xml formats of the data based on the selections of time, station, provider, variable and quality control. The data is categorized into the two datasets below and available according to your restriction level access.
MADIS Text/XML Viewer accounts are recommended for those who have a need for data on-demand, as contrasted with continuous real-time access. In general, users who require a continuous datafeed will get better performance by accessing the data via ftp or LDM. Also note that at this time the Text/XML viewer currently only supports the MADIS surface observation datasets.
The surface analyses grids assimilate all of the MADIS
surface datasets (including the highly-dense integrated mesonet data).
The grids are produced by the Rapid Update Cycle (RUC) Surface
Assimilation System (RSAS),
which incorporates a
15-km grid stretching from Alaska in the north to Central America in
the south, and also covers significant oceanic areas. The RSAS grids
are valid at the top of each hour, and are updated every 15 minutes.
For users interested in the MADIS RSAS grids, the RSASDUMP utility can be used to output the data in plain text.
Quality Control Statistics
To view a current list of surface provider QC Summary Messages available in an hourly, daily, weekly, or monthly output, please click here.
MADIS data files are compatible with:
- AWIPS-I and AWIPS-I-like display systems
- the following analysis software:
- Local Analysis and Prediction System (LAPS)
- Weather Research and Forecasting (WRF) Model Variational Data Assimilation System
- Atmospheric Model Evaluation Tool (AMET)
- Advanced Regional Prediction System (ARPS)
- Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPStm)
- The current observation pre-processor package that's part of the Weather Research and
Forecasting (WRF) variational data assimilation package includes a converter that will convert some of the MADIS datasets into
the little_r text format that is then sent to the variational analysis. The MADIS datasets that are currently supported include
mesonet, aircraft, ASOS and other METAR, Canadian SAO's, maritime (including ships, buoys and C-MAN stations), radiosondes, aircraft, and GOES
- The AMET tool is provided to the air quality modeling community by the Community Modeling & Analysis System at the
University of North Carolina at Chapel Hill.
Please address any questions to the MADIS Help Desk at firstname.lastname@example.org.
Last updated 25 July 2018