METAR Data

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Dataset Coverage of METARStations near Tasmania, Australia.

The NCEP ADP METAR (Aviation Routine Weather Report) dataset is based on measurements from various airports and permanent weather observation stations around the globe. Currently, about 5000 stations are included in this global dataset. An example of the spatial coverage is shown in the figure to the right for the available stations near Tasmania, Australia.

Data Example

The purpose of the METARs is to provide guidance for pilots and the aviation industry, however some stations may also prove useful for the wind energy industry as reports of wind speed, wind direction and temperature are available, see the sample in the figure below.

METAR data from the Launceston Airport in Australia. This airport provides data every 30 minutes.

Considerations

Spike in METAR Wind Report for the Mount Sant’Angelo Station.

When applying this dataset, please consider the following issues:

  1. The reporting frequency varies: Some stations report a few days per year, others only during daytime hours, while others report continuously with 10, 30 minute or hourly intervals. Some stations may only report a period within the hour (e.g. last ten minutes).
  2. The position of the station may be uncertain. Typically latitude and longitude is only reported with an accuracy of two decimals (with position in decimal degrees).
  3. The height of the meteorological mast is uncertain, often 5, 10 or 30 meter masts are used; however the standard is 10 meters.
  4. Since an automated data collection procedure is used at NCAR; then errors may occur in data (such as spikes, see the figure right) and position encoding.

Please take proper care to validate the METAR data against local measurements and to validate the position against local maps. This dataset is processed by EMD and originates from the NCAR website. For further information about the METAR sites, please consider investigating the online resource at:

http://weather.gladstonefamily.net/site

If you enter the four digit ICAO airport code, you may see additional information about the airport of consideration. You can find the airport code in the source files header in the WindPRO meteo object.

Parameters

The following parameters are available from this dataset. Note that not all parameters are available at all stations.

Table: Overview of Metar parameters.
Parameter Description
year Year (YYYY)
month Month (M)
day Day (D)
hour Hour (H)
min Minute (M)
dir Wind direction (degrees)
wsp Wind speed (m/s)
tmp Temperature (deg C)
tdew Dew point temperature (deg C)
spres Surface pressure (hPa)
gust Gust wind speed (m/s)

Acknowledgement

The METAR data are from the Research Data Archive (RDA) which is maintained by the Computational and Information Systems Laboratory (CISL) at the National Center for Atmospheric Research (NCAR). NCAR is sponsored by the National Science Foundation (NSF). The original data are available from the RDA (http://rda.ucar.edu) in dataset number ds461.0.