clupprich/metar-parser

A Ruby library for METAR weather reports

metar - Downloads and parses weather status¶ ↑

The information comes from the National Oceanic and Atmospheric Association’s raw data source.

Implementation¶ ↑

• Parses METAR strings using a state machine.

Example¶ ↑

This prints the latest weather report for Portland International Airport:

require ‘rubygems’ require ‘metar’

raw = Metar::Raw.new( ‘KPDX’ ) parser = Metar::Parser.new( raw ) report = Metar::Report.new( parser )

puts report.to_s

Data format descrition¶ ↑

• WMO

  • www.wmo.int/pages/prog/www/WMOCodes/Manual/Volume-I-selection/Sel2.pdf (pages 27-38)

  • dcaa.slv.dk:8000/icaodocs/Annex%203%20-%20Meteorological%20Service%20for%20International%20Air%20Navigation/Cover%20sheet%20to%20AMDT%2074.pdf (Table A3-2. Template for METAR and SPECI)

  • booty.org.uk/booty.weather/metinfo/codes/METAR_decode.htm

• United states:

  • www.nws.noaa.gov/oso/oso1/oso12/fmh1/fmh1ch12.htm

  • www.ofcm.gov/fmh-1/pdf/FMH1.pdf

  • weather.cod.edu/notes/metar.html

  • www.met.tamu.edu/class/METAR/metar-pg3.html - incomplete

Other software¶ ↑

Other Ruby libraries offering METAR parsing:

• ruby-metar - github.com/brandonh/ruby-metar

• ruby-wx - hans.fugal.net/src/ruby-wx/doc/

There are many reports (WMO) that these libraries do not parse.

There are two gems which read the National Oceanic and Atmospheric Association’s XML weather data feeds:

• noaa-weather - Ruby interface to NOAA SOAP interface

• noaa - github.com/outoftime/noaa

Interactive map:

• www.spatiality.at/metarr/frontend/

Testing¶ ↑

The tests use a local copy of the weather stations list: data/nsd_cccc.txt

If missing, the file gets downloaded before running tests.