Input forecast (METRo)

From Documentation

This article describe the atmospheric forecast input file of METRo.

Contents 1 Description 1.1 Version and revision date 1.2 Default location 2 Contents 2.1 Mandatory fields 2.1.1 Header 2.1.2 Forecast 2.2 Optionnal fields 3 Data source 3.1 World 3.2 Canada 4 Example

[edit] Description

This file contains the atmospheric forecast needed to METRo to perform a roadcast.

[edit] Version and revision date

• Version: 1.2
• Revision date: March 17th 2008

[edit] Default location

No default location. Atmospheric forecast file must be specified on command line.

[edit] Contents

This file contains the name of the station (region or location) for which this forecast has been emitted, the forecast emission date and time, the time zone of this station and the needed weather elements.

The forecast must be at every 60 minutes following the first forecast time. Forecast must have at least 2 forecast time.

[edit] Mandatory fields

[edit] Header

Field description	Element name
Version number	version
Date of creation	production-date

[edit] Forecast

Field description	Element name	Unit
Date and time of forecasted elements	forecast-time	ISO 8601
Air temperature (1.5 m)	at	Celsius
Dew point (1.5 m)	td	Celsius
Rain precipitation quantity since the beginning of the forecast	ra	mm
Snow precipitation quantity since the beginning of the forecast	sn	cm
Wind speed (10 m)	ws	km/h
Surface pressure	ap	mb
Octal cloud coverage (0-8)	cc	octal

[edit] Optionnal fields

Field description	Element name	Unit
Solar flux	sf	W/m²
Infra-red	if	W/m²

The solar and infra-red flux can be used by adding the options --use-solarflux-forecast and --use-infrared-forecast, respectively, in the command line.

The flux in the heat balance of METRo are used directly instead of being derivate from the octal cloud cover. In the case that both infrared and solar flux are given in the forecast file, the cloud cover is not used but must be in the forecast file anyway.

[edit] Data source

[edit] World

The output of the canadian Global Environmental Model (GEM) can be used as input for atmospheric forecast. This data covers the Earth and are freely available in the GRIB format from the website of Environment Canada.

[edit] Canada

Environment Canada is providing an hourly atmospheric forecast for all the Canada for free in an XML format called Canadian Meteorological Markup Language (CMML). An agreement has to be sign in order to access the data on the internet.

[edit] Example

<?xml version="1.0"?> 
<forecast>
  <header>
      <production-date>2003-11-17T23:00Z</production-date>     
      <version>1.1</version>
      <filetype>forecast</filetype>
      <station-id>ofr</station-id>
  </header>
  <prediction-list>
      <prediction>
          <forecast-time>2003-10-16T00:00Z</forecast-time>
          <at>10.0</at>
          <td>2.0</td>
          <ra>0.0</ra>
          <sn>0.0</sn>
          <ws>20</ws>
          <ap>993.8</ap>
          <cc>3</cc>
          <wd>270</wd>
       </prediction>
      <prediction>
          <forecast-time>2003-10-16T01:00Z</forecast-time>
          <at>10.0</at>
          <td>3.0</td>
          <ra>0.0</ra>
          <sn>0.0</sn>
          <ws>20</ws>
          <ap>993.8</ap>
          <cc>3</cc>
          <wd>300</wd>
      </prediction>
      <prediction>
          <forecast-time>
               ....
  </prediction-list>
</forecast>

METRo I/O files

Station | Observation | Forecast | Roadcast | Configuration

METRo I/O specification

Schema | | Flowchart | Format | Date | Observation QA/QC | Road condition | Station type | Time zone | Layer type | Latitude and longitude

METRo I/O examples

Station | Observation | Forecast | Roadcast | Graphical display

This page is part of the documentation of the METRo software. Back to the table of content.